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We present preliminary results on a single field observed by WHAT, a small-aperture short focal length automated telescope with an 8.2° x 8.2° deg field of view, located at the Wise Observatory. The system is similar to the memb...
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We present preliminary results on a single field observed by WHAT, a small-aperture short focal length automated telescope with an 8.2° x 8.2° deg field of view, located at the Wise Observatory. The system is similar to the members of HATNet (http://cfa-www.harvard.eduh~gbakos/HAT/) and is aimed at searching for transiting extrasolar planets and variable objects. With 5 min integration time, the telescope achieved a precision of a few mmag for the brightest objects. We detect variables with amplitudes less than 0.01 mag. All 152 periodic variables are presented at http://wise-obs.tau.ac.il/.–amit/236/.
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We introduced a simple time gain approximation with a functioned amplitude-color range to image all amplitudes or only selected amplitudes. First, we reduced ground wave amplitudes near to the maximum reflected/diffracted wave amp...
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We introduced a simple time gain approximation with a functioned amplitude-color range to image all amplitudes or only selected amplitudes. First, we reduced ground wave amplitudes near to the maximum reflected/diffracted wave amplitudes of the data. Thus amplitude range of the two dimensional (2D) GPR profile section (radargram) was rescaled by maximum reflected/diffracted wave amplitude values only for displaying the radargram. Second, we rearranged amplitude-color range with a functional approximation which was very important as well as time gain application to pick events according to the aim of the research. Third, we functioned an opaque range to obtain transparent three dimensional (3D) image of the aligned 2D radargrams. We presented 2D and 3D applications to show our approximations.
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A method to create homogenous polarized light based on non-quadrature amplitude modulation is proposed. This method consists in the addition of two fields out of phase different from mπ and in the variation of their amplitudes on...
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A method to create homogenous polarized light based on non-quadrature amplitude modulation is proposed. This method consists in the addition of two fields out of phase different from mπ and in the variation of their amplitudes only for obtaining a resulting field modulated in both phase and amplitude. This principle is used to modulate the vertical component in both phase and amplitude, while the horizontal component is varied in amplitude only keeping constant its phase, thus any amplitude relation and phase difference between components can be created and therefore any polarization state could be obtained. A theoretical model will be shown, and it will be sustained with numerical simulations of several polarization examples.
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摘要 :
A method to create homogenous polarized light based on non-quadrature amplitude modulation is proposed. This method consists in the addition of two fields out of phase different from mπ and in the variation of their amplitudes on...
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A method to create homogenous polarized light based on non-quadrature amplitude modulation is proposed. This method consists in the addition of two fields out of phase different from mπ and in the variation of their amplitudes only for obtaining a resulting field modulated in both phase and amplitude. This principle is used to modulate the vertical component in both phase and amplitude, while the horizontal component is varied in amplitude only keeping constant its phase, thus any amplitude relation and phase difference between components can be created and therefore any polarization state could be obtained. A theoretical model will be shown, and it will be sustained with numerical simulations of several polarization examples.
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We present a general representation for the nucleon distribution amplitudes and for the nucleon to pion transition distribution amplitudes in terms of lightcone wave functions. We apply our formalism to a light-cone constituent qu...
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We present a general representation for the nucleon distribution amplitudes and for the nucleon to pion transition distribution amplitudes in terms of lightcone wave functions. We apply our formalism to a light-cone constituent quark model giving some numerical results for both the classes of observables.
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The article is devoted to studying of stress and displacement amplitude distribution in ultrasonic concentrators of different forms. The modelling of different forms of ultrasonic concentrators was considered in detail that allowe...
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The article is devoted to studying of stress and displacement amplitude distribution in ultrasonic concentrators of different forms. The modelling of different forms of ultrasonic concentrators was considered in detail that allowed to choose an optimal form of concentrator providing maximum amplitude of vibrational speed and uniform stress amplitude distribution across the concentrator section. The modelling was carried out for purpose of the subsequent application of ultrasonic treatment to nanostructured materials. Numerical calculation in the environment of MatLab is carried out and diagrams of dependences of stress and displacement amplitude distribution of conic, exponential, ampoule and two-ampoule forms of concentrators are constructed. Visual distribution models of stresses on the section of concentrators and elastic displacements of material in samples of these forms are constructed, resonance frequencies of longitudinal fluctuations of ultrasonic half-wave concentrators are found in the program Abaqus complex.
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The signal processing algorithm for a PSD(Position Sensitive Detector) using an amplitude modulation/demodulation algorithm is addressed in this paper. Dark currents and the external noises such as daylight and fluorescent lights ...
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The signal processing algorithm for a PSD(Position Sensitive Detector) using an amplitude modulation/demodulation algorithm is addressed in this paper. Dark currents and the external noises such as daylight and fluorescent lights are eliminated by using the amplitude modulation/demodulation and a low pass filter. The proposed amplitude modulation/demodulation method for the PSD sensor is compared with a pulse amplitude modulation method. The proposed amplitude modulation method is proved to be more accurate and robuster than the PAM method by using analysis and experiments. Multiple measurements technique using one PSD sensor by the amplitude modulation/demodulation is also addressed. The power variation of light source is compensated by the normalization process using a divider.
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Complex amplitude holography can be applied to calculate complete electromagnetic field information in the holographic plane, including amplitude and phase, so as to achieve high-precision image reconstruction. Complex amplitude m...
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Complex amplitude holography can be applied to calculate complete electromagnetic field information in the holographic plane, including amplitude and phase, so as to achieve high-precision image reconstruction. Complex amplitude metasurfaces, as ultra-thin and ultra-flat electromagnetic wave regulation elements, have opened a new path for the physical implementation of holograms. However, due to coupling between meta-atoms and manufacturing tolerance, it is impractical to accurately encode holographic metasurfaces. The solution is to reduce the number of different meta-atoms by discretizing amplitude and phase on the holographic plane. Here, we analyze and compare the imaging quality of different complex amplitude holographic metasurfaces in various discretization strategies. Numerical results indicate that reasonable discretization process can simplify the metasurfaces design and achieve well-performing image reconstruction.
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Though piping is one of the largest and most expensive types of components in a plant, piping vibration is seldom monitored in a routine manner. Piping itself rarely fails due to vibration, but the same can not be said for related...
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Though piping is one of the largest and most expensive types of components in a plant, piping vibration is seldom monitored in a routine manner. Piping itself rarely fails due to vibration, but the same can not be said for related components such as supports, welds, valves, etc. Typically the only time piping vibration is monitored is if high vibration is perceived by operators or is expected due to plant operational changes such as uprates or major component replacements. The procedure for a comprehensive piping vibration monitoring program is thus not as widely known as that for other components such as rotating machinery. This paper presents the steps involved with monitoring piping vibration, obtaining meaningful data and ways to interpret the data. It could be viewed as a primer to those who have never been involved with vibration testing on piping, or as a guideline and checklist for those who have.
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摘要 :
Though piping is one of the largest and most expensive types of components in a plant, piping vibration is seldom monitored in a routine manner. Piping itself rarely fails due to vibration, but the same can not be said for related...
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Though piping is one of the largest and most expensive types of components in a plant, piping vibration is seldom monitored in a routine manner. Piping itself rarely fails due to vibration, but the same can not be said for related components such as supports, welds, valves, etc. Typically the only time piping vibration is monitored is if high vibration is perceived by operators or is expected due to plant operational changes such as uprates or major component replacements. The procedure for a comprehensive piping vibration monitoring program is thus not as widely known as that for other components such as rotating machinery. This paper presents the steps involved with monitoring piping vibration, obtaining meaningful data and ways to interpret the data. It could be viewed as a primer to those who have never been involved with vibration testing on piping, or as a guideline and checklist for those who have.
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