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Page "Arago spot" ¶ 42
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point and source
But this is one more demonstration of the point mentioned above ( Commercial economies ), that the newly independent states recognized the importance of a predictable and established body of law to govern the conduct of citizens and businesses, and therefore adopted the richest available source of law.
To the point of some international source referring to it as the " Cham genocide ".
* Computational studies can be carried out to find a starting point for a laboratory synthesis, or to assist in understanding experimental data, such as the position and source of spectroscopic peaks.
Once the ray either encounters a light source, or more probably once a set limiting number of bounces has been evaluated, then the surface illumination at that final point is evaluated using techniques described above, and the changes along the way through the various bounces evaluated to estimate a value observed at the point of view.
In addition, point sources like galaxies and clusters represent another source of foreground which must be removed lest they distort the short scale structure of the CMB power spectrum.
The DW effectively provides a single source of information from which the data marts can read, creating a highly flexible solution from a BI point of view.
In vector calculus, divergence is a vector operator that measures the magnitude of a vector field's source or sink at a given point, in terms of a signed scalar.
In physical terms, the divergence of a three dimensional vector field is the extent to which the vector field flow behaves like a source or a sink at a given point.
If the divergence is nonzero at some point then there must be a source or sink at that position.
The propagation of a wave can be visualized by considering every point on a wavefront as a point source for a secondary spherical wave.
The wave that emerges from a point source has amplitude at location r that is given by the solution of the frequency domain wave equation for a point source ( The Helmholtz Equation ),
If the source is located at an arbitrary source point, denoted by the vector and the field point is located at the point, then we may represent the scalar Green's function ( for arbitrary source location ) as:

point and has
It will be noted that point f has seven nearest neighbors, h and e have six, and p has only one, while the remaining points have intermediate numbers.
In his recent evaluation of Kennedy's potentialities for leadership, Walter Lippmann has cited the `` precision '' of his mind, his `` immense command '' of factual detail, and his `` instinct for the crucial point '' as impressive in the extreme ; ;
When disruptive change has penetrated to the third level of social order, the process of disruption rapidly reaches a point of no return.
His point is simply that the Tories have showered him with personal satire, despite the fact that as a private subject he has a right to speak on political matters without affronting the prerogative of the Sovereign.
Some historians have found his point of view not to their taste, others have complained that he makes the Tory tradition appear `` contemptible rather than intelligible '', while a sympathetic critic has remarked that the `` intricate interplay of social dynamics and political activity of which, at times, politicians are the ignorant marionettes is not a field for the exercise of his talents ''.
At this point, of course, the issue has become complicated by a development unforeseen by Lappenberg and Kemble.
Everyone is more or less sceptical and virtually no one has been willing to accept Lappenberg or Kemble's position on that point.
And now Mr. Hodges has pioneered further into the economic unknown with the announcement that he thinks business has stopped sliding and that it should start going upward from this point.
The gulf between the `` rich '' and the `` poor '' has narrowed, in the industrialized Western world, to the point that the word `` poor '' is hardly applicable.
If design head has a deep cavity, clay lid will be quite thick at this point ; ;
Now, the machine has been improved to a point where it is generally more economical than oil heat at temperatures down to 15 degrees.
The opposition to this point of view has its staunchest support in the work of Miller ( '50 ).
The square has one corner point on the straight line segment, and does not lie entirely in the interior.
In some neighborhood of an isolated tangent point in the f-plane, say Af, the function Af is either double-valued or has no values defined, except at the tangent point itself, where it is single-valued.
Up to this point stress has been placed on roleplaying in terms of individuals.
From the point of view of syntactic analysis the head word in the statement is the predicator has broken, and from the point of view of meaning it would seem that the trouble centers in the breaking ; ;
In such a case, any attitude would be as fitting or unfitting as any other, which means that the notion of fitness has lost all point.
where, of Costaggini, only some foliage has been washed, at the point where his work stopped.
To this point the need for an over-all plan for submarine defense has been demonstrated, the mission has been stated, broad principles delineating its content laid down, and the supporting elements listed.
The effect is that the platform returns from an off-level position at a rapid rate until it is nearly level, at which point the platform is controlled by a proportional servo with low enough frequency response so that the noise has little effect on the leveling process.

point and wavelength
Such a wave travels at well over, but owing to the enormous wavelength the wave oscillation at any given point takes 20 or 30 minutes to complete a cycle and has an amplitude of only about.
Cut-away of spherical wavefronts, with a wavelength of 10 units, propagating from a point source.
Neglecting divergence due to poor beam quality, the divergence of a laser beam is proportional to its wavelength and inversely proportional to the diameter of the beam at its narrowest point.
where is the laser wavelength and w is the radius of the beam at its narrowest point, which is called the " beam waist ".
The rate of change of dispersion with respect to wavelength at the zero-dispersion point is called the zero-dispersion slope.
At values of the ratio of particle diameter to wavelength more than about 10, the laws of geometric optics are mostly sufficient to describe the interaction of light with the particle, and at this point the interaction is not usually described as scattering.
Disadvantages include a lack of bass response ( due to phase cancellation from a lack of enclosure ( bass rolloff 3db point occurs when the narrowest panel dimension equals a quarter wavelength of the radiated frequency for dipole radiators, so for a Quad ESL 63 at 0. 66 meters wide this occurs at around 129 Hz so is comparable to many box speakers.
At this point, if greater resolution is needed at that wavelength, a wider mirror has to be built or aperture synthesis performed using an array of nearby telescopes.
In terms of empirical measurements, the wavelength can only be determined by observing a change in the wave between one point in space and another nearby point ( mathematically, by differentiation ).
In cases where the diameter of a trapped particle is significantly smaller than the wavelength of light, the conditions for Rayleigh scattering are satisfied and the particle can be treated as a point dipole in an inhomogenous electromagnetic field.
In spectroscopy, an isosbestic point is a specific wavelength at which two chemical species have the same molar absorptivity ( ε ) or, more generally, are linearly related.
When an isosbestic plot is constructed by the superposition of the absorption spectra of two species ( whether by using molar absorptivity for the representation, or by using absorbance and keeping the same molar concentration for both species ), the isosbestic point corresponds to a wavelength at which these spectra cross each other.
When a 1-to-1 ( one mole of reactant gives one mole of product ) chemical reaction ( including equilibria ) involves a pair of substances with an isosbestic point, the absorbance of the reaction mixture at this wavelength remains invariant, regardless of the extent of reaction ( or the position of the chemical equilibrium ).
The requirement for an isosbestic point to occur is that the two species involved are related linearly by stoichiometry, such that the absorbance is invariant for one particular wavelength.
The wavelength of the isosbestic point determined does not depend on the concentration of the substance used, and so it becomes a very reliable reference.
This means that as light from the quasar travels through the IGM and is redshifted, wavelengths which had been above the Lyman Alpha limit are stretched, and will at some point be just equal to the wavelength needed for the Lyman Alpha transition.
While in theory all stars or other " point sources " of a given wavelength and seen through a given aperture have the same Airy disk radius characterized by the above equation ( and the same size diffraction pattern ), differing only in intensity ( the " height " of the surface plot at upper right ), the appearance is that fainter sources appear as smaller disks, and brighter sources appear as larger disks.
ATLAS-3 instruments, mounted on a Spacelab pallet in the cargo bay, included Atmospheric Trace Molecule Spectroscopy ( ATMOS ), which collected more data on trace gases in the atmosphere than on all three of its previous flights combined ; Shuttle Solar Backscatter Ultraviolet Spectrometer ( SSBUV ), which took ozone measurements to calibrate ozone monitor on aging NOAA-9 satellite as well as cooperative measurements with other ATLAS-3 instruments ; Active Cavity Radiometer Irradiance Monitor ( ACRIM ), which took extremely precise measurements of the sun's total radiation for 30 orbits as calibration reference for sister instrument on Upper Atmosphere Research Satellite ( UARS ) launched in 1991 ; Measurement of the Solar Constant ( SOLCON ), provided by Belgium, which also measured solar radiation but as reference point to track changes over years ; Solar Spectrum Measurement ( SOLSPEC ), French instrument, measured sun's radiation as function of wavelength ; and Solar Ultraviolet Spectral Irradiance Monitor ( SUSIM ), which collected its highest precision solar ultraviolet radiation measurements in its 15-year lifetime.
By rotating the prism ( in the plane of the diagram ) around any point O on the face AB, the wavelength which is deviated by 60 ° can be selected.
For the white point indicated, the dominant wavelength for " x " is on the nearer perimeter, around 600 nm, while the complementary wavelength is opposite, around 485 nm.
The point of intersection nearer to the color in question reveals the dominant wavelength of the color as the wavelength of the pure spectral color at that intersection point.

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