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Response spatial

Steady-state extrapolation Fourier analysis Gating and signal filtering Transient signals Speeding up of response Spatial and temporal information Enhancement of selectivity Increasing order of measurement... [Pg.318]

A number of experimental parameters have to be optimized in order to obtain the best SPECT image. These include attenuation, scatter, linearity of detector response, spatial resolution of the collimator and camera, system sensitivity, minimization of mechanical movements, image slice thickness, reconstruction matrix size and filter methods, sampling intervals and system deadtime. In a hospital, calibrating and monitoring these functions are usually performed by a Certified Nuclear Medicine Technician or a medical physicist. [Pg.994]

Frequency Spectrum of Noise Signal-to-Noise Ratio Noise-Equivalent Power Specific Detectivity (D ) Linearity and Saturation Frequency Response Spatial Considerations Crosstalk... [Pg.3]

It was found that that in the case of soft beta and X-ray radiation the IPs behave as an ideal gas counter with the 100% absorption efficiency if they are exposed in the middle of exposure range ( 10 to 10 photons/ pixel area) and that the relative uncertainty in measured intensity is determined primarily by the quantum fluctuations of the incident radiation (1). The thermal neutron absorption efficiency of the present available Gd doped IP-Neutron Detectors (IP-NDs) was found to be 53% and 69%, depending on the thicknes of the doped phosphor layer ( 85pm and 135 pm respectively). No substantial deviation in the IP response with the spatial variation over the surface of the IP was found, when irradiated by the homogeneous field of X-rays or neutrons and deviations were dominated by the incident radiation statistics (1). [Pg.507]

The most significant symmetry property for the second-order nonlinear optics is inversion synnnetry. A material possessing inversion synnnetry (or centrosymmetry) is one that, for an appropriate origin, remains unchanged when all spatial coordinates are inverted via / —> - r. For such materials, the second-order nonlmear response vanishes. This fact is of sufficient importance that we shall explain its origm briefly. For a... [Pg.1273]

The higher-order bulk contribution to the nonlmear response arises, as just mentioned, from a spatially nonlocal response in which the induced nonlinear polarization does not depend solely on the value of the fiindamental electric field at the same point. To leading order, we may represent these non-local tenns as bemg proportional to a nonlinear response incorporating a first spatial derivative of the fiindamental electric field. Such tenns conespond in the microscopic theory to the inclusion of electric-quadnipole and magnetic-dipole contributions. The fonn of these bulk contributions may be derived on the basis of synnnetry considerations. As an example of a frequently encountered situation, we indicate here the non-local polarization for SFIG in a cubic material excited by a plane wave (co) ... [Pg.1279]

SFIG or SFG from a medium that has a strong response in a separate detection anu. By this means, one may fiilly compensate for variations not only in pulse energy, but also in the temporal and spatial substructure of the laser pulses. Some experiments may require measurement of the phase of the nonlinear signal [57]. [Pg.1281]

The spatial and steric requirements for high affinity binding to protein kinase C (PKC), a macromolecule that has not yet been crystallized, were determined. Protein kinase C plays a critical role in cellular signal transduction and is in part responsible for cell differentiation. PKC was identified as the macromolecular target for the potent tumor-promoting phorbol esters (25). The natural agonists for PKC are diacylglycerols (DAG) (26). The arrows denote possible sites of interaction. [Pg.240]

The site was a drained marsh which received no artificial N inputs, although cattle were present on the site until a couple of weeks before the experiment. NjO emissions were measured by chamber techniques as no instrumental techniques were sensitive enough at that stage to permit micrometeorological measurements. Although spatially very variable, the mean emission rate from the site was 4ng NjO-Nm s h The sporadic measurements made impossible the determination of any response to temperature or water status. [Pg.75]

The basic phenomenon was observed in modeling studies by Bjoreskov and Slinko (1965) that sudden increase in inlet temperature caused a transient drop of the peak temperature. The wrong-way response name was given by Mechta et al (1981) after they experienced the opposite a sudden of inlet temperature resulted in an increase of the peak temperature (which may eventually cause a runaway.) The work used a pseudo-homogeneous reaction model and explained the phenomenon by the different speeds of transient response in gas and solid. The example in the last part of Chapter 7.4 explained the speed difference by the large difference in heat capacity of gas and solid phases. For this a two-phase model is needed and spatial and time changes must be followed. [Pg.207]

The significance of instrument band width and modulation transfer function was discussed in connection with Equation (3) to characterize the roughness of nominally smooth surfaces. The mechanical (stylus) profilometer has a nonlinear response, and, strictly speaking, has no modulation transfer function because of this. The smallest spatial wavelength which the instrument can resolve, 4nin> given in terms of the stylus radius rand the amplitude aoi the structure as... [Pg.720]

Iha pharmacological response elicited by monocyclic aromatic iigents is a function of the number and spatial arrangement of the functional groups attached to the aromatic ring this is true of a great many drugs. [Pg.55]

I he diverse range of phannacological actions of this structural class documents the belief that the naphthalene nucleus consists of a scaffold upon which vanous functional groups can be arranged tnd that the action elicited is a consequence of receptor response to the kind and spatial arrange ment of these functions... [Pg.55]


See other pages where Response spatial is mentioned: [Pg.95]    [Pg.95]    [Pg.209]    [Pg.445]    [Pg.664]    [Pg.1096]    [Pg.1279]    [Pg.1298]    [Pg.1542]    [Pg.1632]    [Pg.1940]    [Pg.2563]    [Pg.313]    [Pg.242]    [Pg.182]    [Pg.339]    [Pg.290]    [Pg.292]    [Pg.160]    [Pg.162]    [Pg.241]    [Pg.194]    [Pg.420]    [Pg.429]    [Pg.211]    [Pg.310]    [Pg.158]    [Pg.356]    [Pg.721]    [Pg.733]    [Pg.65]    [Pg.212]    [Pg.213]    [Pg.803]    [Pg.994]    [Pg.399]    [Pg.437]    [Pg.92]   
See also in sourсe #XX -- [ Pg.357 , Pg.373 ]




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Dielectric response spatially varying

Shaping of the spatial response

Spatial patterning of response

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