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BackgroundSextupoles are an important component of storage ring octonal unit in high energy synchrotron radiation sources. They require complex technological processes and precise center extraction. Therefore, it is necessary to find out the most reasonable calibration scheme for the mechanical center.PurposeThis study aims at the calibration scheme for the mechanical center extraction of high energy photon Ssurce (HEPS) sextupoles, and obtaining the corrected mechanical central coordinate system.MethodsThe method of directly measuring the reference plane of the sextupole was adopted for the mechanical center calibration of magnets. By rotating the conventional calibration coordinate system with a given pole seam deviation angle, the three polar seam surfaces were brought closer to the theoretical positions to decrease the main diagonal component of the sextupoles. The mechanical center calibrations were performed twice for each hexacode iron to further reduce the impact of the polar seam error.ResultsThe calibration results show that the calibration repeat accuracy is 0.005 mm for the sextupole. The standard deviation between the measured value and the design value of the pole seam spacing is 0.015 mm. Additionally, the standard deviation of the reference point before and after the rotation of the coordinate system is 0.09 mm, with a maximum rotation angle of 0.6 mrad.ConclusionsThe calibration scheme of this study can be used to improve the calibration accuracy and provide reference for the calibration of similar equipment. It ensures smooth installation of accelerator devices and is of significant importance for accelerator collimation measurements.

Elastic reverse-time migration (ERTM), which utilizes the advantages of both P- and S-wave modes, is a widely used application for imaging in 3D anisotropic media. However, crosstalk due to intrinsically coupled P- and S-wavefields may degrade the image quality. To solve this problem, this study presents an effective vector P- and S-wavefield decomposition scheme in ERTM that can improve the images of 3D transversely isotropic (TI) media. The proposed method consists of four steps: (1) rotating the observation coordinate system to align its vertical axis with the symmetry axis of 3D TI media; (2) deriving the formulations of the 3D TI decomposition operator by applying the VTI P/S wave-mode decomposition strategy based on eigenform analysis in the new coordinate system; (3) implementing vector P- and S-wavefield decomposition by constructing the 3D TI Poisson equation, and introducing a novel and efficient method based on the first-order Taylor expansion to accelerate the computational efficiency of the decomposition; and (4) applying a vector-based dot-product imaging condition to generate PP and PS images. Compared with previous studies, the algorithm of our proposed method in 3D TI media is both numerically stable and computationally efficient. The 3D TI decomposition operator generates vector P- and S-wavefields showing the correct amplitude/phase with the input ones. Several numerical examples illustrate the satisfactory performance of the proposed 3D TI decomposition operator and the effective image improvement. [ABSTRACT FROM AUTHOR]

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There exist several limitations in the calculation of the earth's gravity field based on the measurement data at the centroids of geographic grid cells. To address these issues, we propose using the hexagonal geodesic discrete global grid system in the spherical harmonic (SH) analysis and synthesis of the earth's gravity field. We show that using interpolation of the associated Legendre functions (ALFs) and transformation of the SH coefficients (SHCs) with rotation improves the efficiency of SH synthesis with non-equal latitudinal quasi-hexagonal grid points. Our analysis also indicates that the global SH analysis (GSHA) with the quasi-hexagonal grids significantly reduces the number of necessary observations while ensuring the accuracy of the recovered SHCs. The results in this paper also confirm that both methods based on ALFs interpolation and SH rotation can quickly compute the synthetic gravity anomalies with the accuracy level of 10–11 mGal. It is also seen that in GSHA, using the ISEA4H grid saves ~ 37% necessary observations compared with the classic geographic grid without any appreciable loss of accuracy. Moreover, it could reduce the aliasing of power from the higher to lower degrees in GSHA considerably, which is one of the important factors affecting the consistency of the earth's gravitational model with the real gravity field. [ABSTRACT FROM AUTHOR]

Gram–Schmidt orthogonalization is a popular fundamental technique of linear algebra, having wide-spread applications in state-of-the art and next-generation signal processing and communication technologies including Blind Source Separation, Independent Component Analysis, MIMO technology, Orthogonal Frequency Division Multiplexing, and QR Decomposition. On the other hand, Coordinate Rotation Digital Computer (CORDIC) is a technique being extensively used for the efficient implementation of complex arithmetic operations in various signal processing and communication modules. For all the aforementioned applications including FastICA and QR decomposition, CORDIC is being used widely for all the modules except GS where still costly multipliers, dividers, square root, and addition operations are being used. It motivated us to investigate the design for GS using CORDIC resulting in low-power and low-complex architecture of the entire design. In this paper, we propose a CORDIC-based low-complexity, low-power architecture design methodology for the n-dimensional GS algorithm where a single CORDIC unit can be re-used for implementation of several processing and communication modules on-chip. The proposed architecture precludes the use of additional arithmetic units to perform costly operations by recursive use of CORDIC, and thus significantly reduces its hardware complexity. The proposed architecture reduces the power consumption by 74–86 % and the area by 12–40 % for 3D to 6D GS, respectively, over the conventional approach. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the impulse interference near the service frequency band of aviation radio navigation affects the receiver, and further improve the anti-jamming ability of GNSS system, a impulse interference suppression method based on STFRFT (short time fractional Fourier transform) was proposed. The optimal rotation order of the received signal was determined, and STFRFT was applied to the signal to obtain the two-dimensional distribution of time-frequency surface through coordinate rotation. Under the optimal order, the adaptive time-varying filter was used to separate the interference and the signal, so as to suppress the interference. The simulation results show that the adaptive filtering algorithm based on STFRFT has the best effect of eliminating interference compared with several traditional methods, and retains more useful signals while suppressing impulse interference. By combining STFRFT and adaptive time-varying filtering technology, the ability of suppressing impulse interference is improved, which provides some reference for the impulse anti-jamming technology of aviation radio navigation service.

We use Pn tomography with coordinate rotation to image in Alaska and adjacent areas and obtain a new Pn velocity and anisotropy model. The observed Pn velocities correlate well with the local geological structures. Low Pn velocities are observed beneath the Aleutian volcanic arc, which may reveal partial melting related to plate dehydration. However, it is separated by a distinct high‐velocity anomaly, suggesting a slab tear. The slightly low Pn velocities beneath the Denali volcanic gap suggest that a small amount of magma is produced but is insufficient to form surface volcanoes. We observe sharp bending of the fast directions on the two sides of the northeast edge of the Yakutat Plate, which reveals the plate's bending. Large‐scale low velocities are observed beneath the northwestern Cordillera, which may be due to the upwelling of hot material from the deep mantle. The Pn fast directions are parallel to the Queen Charlotte‐Fairweather fault system, consistent with the shear strain direction of the faults, reflecting that the influence of the plate boundary is far‐reaching and that the deformation of the crust and the upper mantle is coupled. Our study provides new constraints on the complex deformation beneath Alaska and adjacent areas. Plain Language Summary: The Pacific Plate and Yakutat microplate are subducted beneath the North American plate, resulting in complex geological structures and ongoing volcanic activities in Alaska. We used an improved seismic imaging method to invert the velocity and anisotropy of the uppermost mantle in Alaska. In our new model, the low velocities may show the distribution of magma sources of surface volcanoes in the uppermost mantle. The discontinuity of low velocities beneath the Aleutian volcanic arc may indicate that the plate was torn during subduction. A slightly low‐velocity anomaly was observed beneath the Denali volcanic gap, indicating the production of molten material, but not enough to form surface volcanoes. The anisotropy parallel to the trench and transition faults reflects the olivine crystal arrangement direction in the uppermost mantle. This study provides more information on the plate collision and subduction processes. Key Points: We use improved Pn tomography method with coordinate rotation to image uppermost mantle structure of AlaskaLow Pn velocities beneath the Aleutian volcanic arc are separated by distinct high velocity beneath Cook Inlet Basin suggesting a slab tearThe anisotropic structure beneath Queen Charlotte‐Fairweather fault system reveals the coupling of the crust and upper mantle deformation [ABSTRACT FROM AUTHOR]

• Model based recursive partitioning (MOB) can refine sector-wise planar fitting. • The approach can automate finding the relevant wind sectors for a planar fit. • The method allows sector-wise planar fitting to consider other variables. • Coordinate rotation during unstable periods might not need to be performed. While the use of three-dimensional sonic anemometers for eddy covariance is well established, there remain questions about its deployment and consequent data analysis. Convention has largely accepted that coordinates must be rotated so that the corrected transverse and vertical mean velocities become zero. In non-ideal terrain, a planar fit coordinate rotation is widely accepted. However, if the coordinate system changes through time, such as in a rapidly growing maize canopy, or is affected by the local topography, finding temporally and directionally stable regions for a reference point is crucial for flux estimation. A model-based recursive partitioning (MOB) algorithm is proposed to answer this problem. The algorithm creates individual wind sectors and accounts for temporal or spatially dependent variables that may affect planar fits. A cross-validation fitting procedure of the MOB algorithm has proved crucial in identifying variables that influence the choice among different parametric models, such as day of year, solar altitude, and wind direction. Momentum exchange is the most sensitive to alternative coordinate rotation systems, especially in stable conditions. The MOB methodology would be most useful during these conditions. The analyses presented here show that in quantifying scalar fluxes during the day, especially in the case of sensible heat flux and by extension to evapotranspiration and carbon dioxide exchange, there is little need for coordinate rotation if the sensors were aligned with the vertical parallel to gravity. [ABSTRACT FROM AUTHOR]

Machine learning (ML) models provide useful tools to generate spatial estimations of geological features, but they do not consider the spatial dependence among the observations and they primarily use coordinates as predictors. Thus, many ML models produce visible artifacts in the resulting estimates along the coordinate directions. To overcome this significant problem, this paper presents an ensemble super learner (ESL) model which uses the super learner (SL) model as the ML model. In the ESL model, numerous training sets are created from the original dataset by a coordinate rotation strategy and then the estimates obtained from the fitted SL models are ensembled to produce a final estimate. A dataset from a high-grade gold deposit demonstrates the approach and compares the results to kriging and the SL model. The results demonstrate that the ESL model manages artifacts in ML spatial estimation. It also provides better results than the kriging and SL model in terms of estimation accuracy. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hebei University of Science & Technology is the property of Hebei University of Science & Technology, Journal of Hebei University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper proposes an $n$ -dimensional Simplex FastICA (FICA), an accelerated and low complex architectural design methodology for FICA to attain high computation speed targeted for resource-constrained applications. This is achieved by exploiting the algorithmic redundancies of FICA that make the proposed Simplex FICA faster than the conventional FICA without adding any extra architectural complexities. The proposed methodology has been verified and validated by applying it for separating 6D EEG signals. Subsequently, the corresponding hardware has been designed using Verilog HDL. It is synthesized using UMC 90-nm technology resulting in 0.5703-mW power and 0.495 mm2 area at 1.08 V. The computation time saving for 4D–12D FICA was computed by varying the number of iterations of convergence for the $n\text {th}$ stage from 2 to 4 for 4096 samples. The average percentage of computation time saved for $n\text {th}$ stage achieved with the proposed methodology in comparison to the state of the art varies from 99.783% to 99.891%. The overall average percentage of computation time saving for the proposed design with the aforementioned specifications varies from 9.14% to 16.6%. [ABSTRACT FROM AUTHOR]

Summary: Electricity consumption has been increasing worldwide, and the growth is still significant, particularly in developing countries. When power consumption increases, the entire system is at a risk of voltage collapse. Power distribution companies have been using step‐up transformers or on‐load tap changing systems to overcome this crucial challenge. These devices are capable of increasing voltage and consequently promoting static voltage stability margin of the network. To use such equipment, it is essential to determine the optimal location and voltage ratio. This paper analytically investigates the presence of a step‐up transformer in a medium‐voltage radial feeder for improving voltage stability. The paper also introduces an easy‐to‐use coordinate rotation that provides a more tangible graphical representation of static stability of power systems. Furthermore, an open‐source software application, developed by the authors, to calculate voltage stability limit of power systems is introduced in this paper that is publicly available. [ABSTRACT FROM AUTHOR]

This paper investigates processing of fast-response data and corrections of turbulent fluxes obtained by using eddy covariance method based on data collected at an offshore observation tower during three Coldintrusion (CI) events in the South China Sea in 2010. This study presents the data processing procedure in detail and compares frictional velocities (u*), sensible heat fluxes (H) and latent heat fluxes (LE) yielded by using different averaging periods and different coordinate rotation methods; evaluates the sonic temperature correction for sensible heat flux and the Webb correction for latent heat flux as a function of 10 m wind speed (u10) during the CIs. The results show (1) that the different averaging periods of 30 min and 10 min cause biases of u*(H,LE) within 5% (15%, 62%). The values of u(u* H,LE) averaged from 30 mins are mostly larger than those averaged from 10 mins. We suggest that the averaging period of 10 min is not sufficiently long to capture all scale eddies and recommend 30 min averaging period in calculating turbulent fluxes using eddy covariance method during CIs; (2) that the values of u*(H,LE) obtained from double rotation (DR2) and those obtained from planar fit rotation (PF) have good agreements and correlation coefficients between them are larger than 0.99. BecausePF method requires unchanged environment and it is easier to applyDR2 method, we suggestDR2 coordinate rotation method in processing fast-response data; and (3) that the median values of frictional velocity (sensible heat flux and latent heat flux) binned according to 2 m s-1 intervals of u10 increase (decrease, increase) by less than 9% (4%, 10%) by Coriolis corrections (sonic temperature corrections, Webb corrections), which decreases (decreases, increases) with increasing u10when u10are 5-17 m s-1. [ABSTRACT FROM AUTHOR]

In order to move the polar singularity of arbitrary spherical harmonic expansion to a point on the equator, we rotate the expansion around the y-axis by $$90^{\circ }$$ such that the x-axis becomes a new pole. The expansion coefficients are transformed by multiplying a special value of Wigner D-matrix and a normalization factor. The transformation matrix is unchanged whether the coefficients are $$4 \pi $$ fully normalized or Schmidt quasi-normalized. The matrix is recursively computed by the so-called X-number formulation (Fukushima in J Geodesy 86: 271-285, 2012a). As an example, we obtained $$2190\times 2190$$ coefficients of the rectangular rotated spherical harmonic expansion of EGM2008. A proper combination of the original and the rotated expansions will be useful in (i) integrating the polar orbits of artificial satellites precisely and (ii) synthesizing/analyzing the gravitational/geomagnetic potentials and their derivatives accurately in the high latitude regions including the arctic and antarctic area. [ABSTRACT FROM AUTHOR]

Dispersion analysis is an important part of in-seam seismic data processing, and the calculation accuracy of the dispersion curve directly influences pickup errors of channel wave travel time. To extract an accurate channel wave dispersion curve from in-seam seismic two-component signals, we proposed a time-frequency analysis method based on single-trace signal processing; in addition, we formulated a dispersion calculation equation, based on S-transform, with a freely adjusted filter window width. To unify the azimuth of seismic wave propagation received by a two-component geophone, the original in-seam seismic data undergoes coordinate rotation. The rotation angle can be calculated based on P-wave characteristics, with high energy in the wave propagation direction and weak energy in the vertical direction. With this angle acquisition, a two-component signal can be converted to horizontal and vertical directions. Because Love channel waves have a particle vibration track perpendicular to the wave propagation direction, the signal in the horizontal and vertical directions is mainly Love channel waves. More accurate dispersion characters of Love channel waves can be extracted after the coordinate rotation of two-component signals. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper introduces a modified edition of classical Cespedes' load flow method to radial distribution system analysis. In the developed approach, a distribution network is modeled in different complex reference systems and reduced to a set of connected equivalent subnetworks, each without resistance, while graph topology and node voltage solution are preserved. Active power losses are then not dissipated in the modeled subnetworks and active power flows can be obtained as a consequence of radiality. Thus, the proposed method preprocesses a series of variable transformations concomitant to an iterative algorithm using a forward-backward sweep to arrive at the load flow solution. The proposed approach has been tested using literature and actual distribution networks, and efficiency improvements are verified in comparison to Cespedes' load flow method. [ABSTRACT FROM AUTHOR]

This study conducted both experiments and simulations of gas metal arc welding of horizontal fillet joints with different welding speeds and wire feed rates. Front and side arc images were respectively captured by a CCD camera placed in front of the workpiece and beside it in each experiment. The arc models, including surface heat flux, electromagnetic force, arc pressure and drag force, were formulated in a rotated ( x ′– y ′– z ′) coordinate system whose z ′-axis was consistent with the arc axis. A higher welding speed made the arc behaviors less stable and may induce undercut on the vertical plate, whereas a higher wire feed rate enhanced the stability of arc behaviors. The arc images were analyzed to determine the effective arc radii of the arc models by applying both the Abel inversion technique and Fowler–Milne method. The radial distance, vertical distance and material thickness were calculated respectively to approximate the electromagnetic force distributions, and the resultant electromagnetic force distributions were analyzed in details. The resultant arc models were subsequently used to simulate each welding experiment. The molten pool behaviors by different welding speeds and wire feed rates were compared and analyzed, and the simulation models were verified by comparing the experimental and simulation results. [ABSTRACT FROM AUTHOR]

In this paper we study a class of derivative-free unconstrained minimization algorithms employing nonmonotone inexact linesearch techniques along a set of suitable search directions. In particular, we define globally convergent nonmonotone versions of some well-known derivative-free methods and we propose a new linesearch-based nonmonotone algorithm, where search directions are constructed by combining coordinate rotations with simplex gradients. Through extensive numerical experimentation, we show that the proposed algorithm is highly competitive in comparison with some of the most efficient direct search methods and model based methods on a large set of test problems. [ABSTRACT FROM AUTHOR]

Abstract: This paper puts forward a novel fast algorithm of three-dimensional Computer-Generated Hologram (CGH). The algorithm proposed can directly express the two-dimensional Fourier spectrum of a unit square by an analytic function, as well as the light field distribution of the unit square on the holographic plane (the unit square is not parallel to the holographic plane). The computer simulation and photoelectric reconstruction are also performed to verify the algorithm. The experimental results show that the algorithm is quick and simple, providing a good reference to research on three-dimensional CGH. [Copyright &y& Elsevier]

We propose a new method to compute the phase-only computer-generated hologram (CGH) that can modulate an image on a tilted plane. We used the fractional Fourier transformation to compute light propagation between the hologram plane and the tilted plane. The phase-only hologram was obtained by an iterative algorithm. We proposed a method to calculate the inverse optical propagation from the hologram plane to a tilted plane by coordinate rotation and a simple interpolation in the Fourier domain. The experimental results show that the projected image on the tilted plane can be reconstructed by a phase-only hologram generated by our iterative algorithm. We also show that the quality of the projected image on the tilted plane is better than the image projected by the phase hologram generated by traditional method. [ABSTRACT FROM PUBLISHER]

• New variant of subset simulation is proposed for reliability analysis. • Magnify input variability along important directions to enhance sampling efficiency. • The developed method is suitable for problems with small failure probability. • Five benchmarks are used to assess the performance. This paper proposes a generalized subset simulation (GSS) method for estimating small failure probability. The basic idea is to modify the failure threshold and amplify the variability of input variables simultaneously in a sequential way. With a proper choice of the intermediate failure thresholds and amplification factors, the problem of estimation of a small failure probability is decomposed into the problem of estimating a series of simple integrals. For high-dimensional problems, two coordinate rotation schemes are introduced to detect the important directions in high-dimensional space. Using coordinate rotation, original high-dimensional integrals are transformed into a series of low-dimensional ones, and they can be estimated by Markov Chain Monte Carlo (MCMC) simulation technique efficiently. Two MCMC algorithms are introduced within GSS for low-dimensional and high-dimensional problems respectively, and a resampling method is utilized to select the initial states of each Markov chain from the existing samples. Five widely used benchmark examples are used to test the performance of the proposed method. [ABSTRACT FROM AUTHOR]

Abstract: Vertical divergence of CO2 fluxes is observed over two Midwestern AmeriFlux forest sites. The differences in ensemble averaged hourly CO2 fluxes measured at two heights above canopy are relatively small (0.2–0.5μmolm−2 s−1), but they are the major contributors to differences (76–256gCm−2 or 41.8–50.6%) in estimated annual net ecosystem exchange (NEE) in 2001. A friction velocity criterion is used in these estimates but mean flow advection is not accounted for. This study examines the effects of coordinate rotation, averaging time period, sampling frequency and co-spectral correction on CO2 fluxes measured at a single height, and on vertical flux differences measured between two heights. Both the offset in measured vertical velocity and the downflow/upflow caused by supporting tower structures in upwind directions lead to systematic over- or under-estimates of fluxes measured at a single height. An offset of 1cms−1 and an upflow/downflow of 1° lead to 1% and 5.6% differences in momentum fluxes and nighttime sensible heat and CO2 fluxes, respectively, but only 0.5% and 2.8% differences in daytime sensible heat and CO2 fluxes. The sign and magnitude of both offset and upflow/downflow angle vary between sonic anemometers at two measurement heights. This introduces a systematic and large bias in vertical flux differences if these effects are not corrected in the coordinate rotation. A 1h averaging time period is shown to be appropriate for the two sites. In the daytime, the absolute magnitudes of co-spectra decrease with height in the natural frequencies of 0.02–0.1Hz but increase in the lower frequencies (<0.01Hz). Thus, air motions in these two frequency ranges counteract each other in determining vertical flux differences, whose magnitude and sign vary with averaging time period. At night, co-spectral densities of CO2 are more positive at the higher levels of both sites in the frequency range of 0.03–0.4Hz and this vertical increase is also shown at most frequencies lower than 0.03Hz. Differences in co-spectral corrections at the two heights lead to a positive shift in vertical CO2 flux differences throughout the day at both sites. At night, the vertical CO2 flux differences between two measurement heights are 20–30% and 40–60% of co-spectral corrected CO2 fluxes measured at the lower levels of the two sites, respectively. Vertical differences of CO2 flux are relatively small in the daytime. Vertical differences in estimated mean vertical advection of CO2 between the two measurement heights generally do not improve the closure of the 1D (vertical) CO2 budget in the air layer between the two measurement heights. This may imply the significance of horizontal advection. However, a reliable assessment of mean advection contributions in annual NEE estimate at these two AmeriFlux sites is currently an unsolved problem. [Copyright &y& Elsevier]

The article presents a study which analyzes uncertainties and errors in time-integrated eddy correlation data for forest sites in the Amazon. It explores possible advective losses of carbon dioxide emissions for the specific situation of flux measurements at two Amazon forest sites. Based on results, it shows that uncertainties and errors caused by data spikes, delay corrections, and high-frequency loss are small.

• In the case of the minimum number of TDOA measurements, a closed-form method is proposed to determine the source direction conditionally. • A geometry-aided scheme of direction estimation is proposed to eliminate the GDOP effect when using more than two TDOA measurements at a sensor array. • When using the sub-minimum TDOA measurements, a direction estimation method and the corresponding weighted-sum scheme are also developed. • The theoretical estimation errors of the above two methods are analyzed. The paper focuses on the time-difference-of-arrival (TDOA)-based direction estimation of plane wave from a signal-emitting source by spatial array. In order to avoid the potential impact of geometric dilution of precision (GDOP) on estimation accuracy, we propose that the minimum measurements (i.e. only two TDOAs) are used to deterministically calculate the source direction without involving numerical techniques. It is however challenging to algebraically obtain the common solution of two measurement equations in original nonlinear form. By making use of the TDOA invariance to coordinate system rotation, a novel closed-form method is proposed to tackle the above problem via a well-ordered coordinate rotation. Then, we develop a weighted-sum scheme to combine the minimum measurements based individual direction estimates with their weights determined by GDOP. The theoretical estimation mean and variance of the proposed geometry-aided scheme have been derived. The equation curve of TDOA measurement is also geometrically interpreted in the paper. Computer simulations demonstrate the superior performance of this scheme over other similar estimators in the literature, which involve the grid-scan technique, the sub-minimum-measurement scheme, and the linear least squares method. It is validated that the proposed scheme considerably outperforms the other closed-form estimators and achieves estimation accuracy similar to numerical technique but with significantly reduced computational complexity. [ABSTRACT FROM AUTHOR]

Abstract: We present a new method for numerically reconstructing holography image on tilted planes within the Fresnel domain. The method is based on the Fresnel diffraction algorithm and object wave rotation transform. By suitable rotation the object wave on recording plane and once fast Fourier transformation this method can be implemented. The proposed method can render the real image of the hologram not only on parallel plane but also on the tilted. Experimental results are presented to demonstrate the method for a single axis rotation. [Copyright &y& Elsevier]