[en] Necessary and sufficient conditions for the transfer function of a passive linear stationary scattering (or resistance) system are found ensuring that minimal systems in this class are determined by their transfer functions up to similarity. The criteria are stated in terms of a Hankel operator the symbol of which is a contractive operator-valued function defined by the transfer function and having the meaning of the inner scattering suboperator of a simple conservative scattering (respectively, resistance) system with the transfer function in question. A connection between the similarity criterion and the corona theorem and its matrix generalizations is revealed

[en] The beam transfer function changes during the RHIC ramp. The response of the RF control loops changes as a result. A state-variable description of the beam and the RF control loops was developed. This description was used to generate a set of feedback matrices that keeps the response of the RF control loops constant during the ramp. This paper describes the state-variable description and its use in determining the K matrices

[en] Bridging the gap between an abstract definition of pseudo-differential operators, such as (-Δ)^γ for -1/2<γ<1/2, and a concrete way to represent them has proved difficult; deriving stable numerical schemes for such operators is not an easy task either. Thus, the framework of diffusive representations, as already developed for causal fractional integrals and derivatives, is being applied to fractional Laplacian: it can be seen as an extension of the Wiener-Hopf factorization and splitting techniques to irrational transfer functions.

[en] This note will tabulate the desired phase and delay offsets for a Stacktail Momentum beam transfer function measurement as a function of beam energy and pickup leg. These phase and delay offsets were computed from beam transfer functions made around April 14, 2000. The StackTail system with these offsets will have a gain slope of about 10 MeV.

No abstract available

[en] Synchronous detection offers an especially powerful instrument of investigation. It enables a signal to be extracted from the noise by narrowing of the analysis band at the expense of the examination time, and in this sense constitutes a very narrow filter synchronised externally on the signal to be examined. It is phase-sensitive, a great advantage in the determination of transfer functions

[en] This paper is concerned with the discussion of passivity results and the characterization of the regenerative versus passive systems counterparts in dynamic systems. In particular, the various concepts of passivity as standard passivity, strict input passivity, strict output passivity and very strict passivity (i.e. joint strict input and output passivity) are given and related to the existence of a storage function and a dissipation function. The obtained results are related to external positivity of systems and positivity or strict positivity of the transfer matrices and transfer functions in the time-invariant case. (paper)

[en] When a person observes an object located at a distance closer than his near point, the object will appear blurred. Inserting a circular pinhole with a suitable diameter in front of the eye improves vision. However, vision worsens below a certain pinhole diameter, due to diffraction and increasing darkness. In this paper, the effect of the pinhole diameter on observation quality is investigated by determining the optical transfer function of the eye lens–pinhole system. A quantity that is a criterion for image quality is defined, then, it is calculated as a function of the pinhole diameter. This treatment shows that, even for a definite eye, the optimum and also minimum values of pinhole diameter depend on the object distance. (paper)

[en] It is important to monitor the spatial resolution of a gamma camera on a weekly basis to acquire medical images with accurate quantitative information. A simple and fast computer program with a graphical user interface to analyze spatial resolution was successfully developed using MATLAB. The results were compared with those obtained from the standard processing system available in our gamma camera. The spatial resolution calculated using MATLAB was 1.24% lower than using the standard processing system. The developed program is cost effective, faster, and provides an easy platform for the physicists and technologists to analyze the spatial resolution based on the image of the line source.

[en] The transfer function comprised of (2n + 1) poles unit spaced in the ω direction on the line s = -D in the s plane is analyzed in the time domain and shown to have the response F/sub n/(t) = C/sub n/e/sup -Dt/sin/sup 2n/(t/2), providing a clean pseudo-gaussian pulse. If D = 1.5, the afterpulses are theoretically down by about a factor of 8 x 10^-5 and are experimentally acceptable. Experimentally, such an analog signal processor (D = 1.5, n = 3, unit time = 20 us.) shows excellent shift vs. input rate