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Missing information function

Daudel and co-workers (Daudel 1953, 1968 Daudel et al. 1955 Aslangul et al. 1972) were the first to provide a definition of the localization of electrons based solely upon information contained in the state function. They proposed that information theory (Shannon 1948) be used to define the best division of a system into regions or loges . According to this theory our knowledge about a given system is a maximum when the missing information function /(F ,Q) is minimized where... [Pg.333]

In this instance our knowledge of the system would be maximal as we would know with certainty that n electrons are in fl and (N — n) in fl. Correspondingly, in this case I(P, Cl) approaches zero. At the other extreme, when all events are equally probable, our knowledge of the specific state of the system is minimal and the missing information function is maximized. [Pg.333]

It was indeed possible in these molecules to partition total space into regions so that the missing information function was simultaneously minimized for each region. The quantum probabilities were in each case dominated by P2(P.) and the most probable partitioning was found to be the one in which pairs of electrons were localized in well-defined regions of space. [Pg.334]

The study by Daudel et al. (1974a,b) also showed that the fluctuation in the average number of particles in a region paralleled closely the behaviour of the missing information function (see Fig. E7.1, for example). The fluctuation in the average number of electrons for a region 2 is defined as... [Pg.335]

MPDs remind of Daudel s loges [21,22] which also use pv D). There, the idea is to partition molecular space into domains, called loges , and look for ail different possibilities to distribute electrons into them. After some initial trials it was decided to minimize the missing information function. [Pg.175]

It was shown that using the missing information function, as it is done in loge theory, can produce unwanted results. [Pg.183]

The idea of loges was adopted in 1974 by Bader and Stephens [9, 34] who used the flucmation A Q) in the particle number in region Q instead of the missing information function 7( 2) utilized by Daudel. The A Q) is the difference between the... [Pg.123]

The calculation of the linear discriminant function is presented in Table 4.25 and the values are plotted in Figure 4.30. It can be seen that objects 5, 6, 12 and 18 are not easy to classify. The centroids of each class in this new dataset using the linear discriminant function can be calculated, and the distance from these values could be calculated however, this would result in a diagram comparable to Figure 4.27, missing information obtained by taking two measurements. [Pg.239]

There is a great conceptual advantage in abandoning the missing information 1 P , 2) in favour of the fluctuation A N, 2) to determine the localization of electrons. Lennard-Jones (1952) pointed out that the extent to which a set of indistinguishable particles is spatially localized is determined by the system s pair density, the same distribution function which determines the... [Pg.335]

If a reader s favorite program is missing, or functionality not suitably elaborated, the author apologizes in advance and invites comments in the event of a new edition of this book being prepared. Quite radical changes and improvements in software can be announced at the near blink of an eye. Thus keeping an interest in new software developments may offer new methods of more effective analysis that can both save time and/or increase the quality of information obtained from powder diffraction data. [Pg.494]

Technologies vary widely in this respect. The chip in Figure 1.6 is generated by a technology that identifies the gene sequence. We are missing information on the structure and the function of the protein, its molecular interac-... [Pg.32]

The stripes of parity information stored on the dedicated drive are calculated using the Exclusive OR function. By using Exclusive OR with a series of data stripes in the RAID, any lost data can easily be recovered. Should a drive in the array fail, the missing information can be determined in a manner similar to solving for a single variable in an equation. [Pg.1589]

The large number of potential applications of semiconductor nanostructures has generated a considerable amount of theoretical works centered on the assessment of the relationships between their linear and nonlinear optical properties and the structural arrangements of sized clusters and their evolution as a function of their size, bringing therefore the missing information that links the atom and the macroscopic crystal. [Pg.45]

NBS scale (which will be referred to here as the 1984 scale ) is seriously out of date, missing information on about 900 compounds. In addition, since 1991 several important publications (both experimental and theoretical) have presented data indicating that portions of the thermochemical scale, as evaluated in 1984, are in need of re-evaluation. Furthermore, recent publications from two laboratories (Mautner and Sieck at the National Institute of Standards and Technology, and Szulejko and McMahon at the University of Waterloo) provided extensive data sets in which equilibrium constants had been determined as a function of temperature, i.e. experimental entropy change determinations had become available. [Pg.734]

The initial idea in our approach was to construct a density functional, which reveals chemical and physical properties of atoms, since the periodicity of the Table is one of the most important and basic cornerstones of chemistry. Its recovery on the basis of the electron density alone can be considered a significant result. In an information theoretical context, the periodicity revealing functional can be interpreted as a quantification of the amount of information in a given atom s density function, missing from the density function of the noble gas atom which precedes it in the periodie table. The results indicate that information theory offers a method for the construction of density functionals with chemical interest and based on this we continued along the same lines and investigated if more chemically interesting information functionals could be constructed. [Pg.162]

The function of this section is to provide an overall framework within which to describe the important aspects of data collection systems in the CPI. As mentioned in the introduction, the emphasis in this chapter will be on methods for identifying the causes of errors that have led to accidents or significant near misses. This information is used to prevent reoccurrence of similar accidents, and to identify the underlying causes that may give rise to new types of accidents in the future. Data collection thus has a proactive accident prevention function, even though it is retrospective in the sense that it is usually carried out after an accident or near miss has already occurred. [Pg.249]

The main function of an incident reporting system (IRS) is to identify recurring trends from large numbers of incidents with relatively minor outcomes, or from near misses. One of the important characteristics of an IRS is that the time and resources required to evaluate an incident and incorporate it into the database must be minimized. This means that the designers of an IRS have to carefully evaluate the benefits and costs of requiring more comprehensive information from each incident that is to be reported. A requirement for too much information will bring the system into disrepute, and too little information will mean that the results are too general to be of any real value. [Pg.252]

February 2006 Don t miss page 12 of the DS of 2678 for example. Check if it applies to you. Tucked away is public information that you were likely to miss (expectedly ). In fact here is a whole series of parts that can t function properly if the duty cycle is greater than 50%. See their datasheet, but a little more closely from now on On page 12 of the 2678 datasheet ... [Pg.299]


See other pages where Missing information function is mentioned: [Pg.246]    [Pg.334]    [Pg.182]    [Pg.182]    [Pg.122]    [Pg.246]    [Pg.334]    [Pg.182]    [Pg.182]    [Pg.122]    [Pg.153]    [Pg.137]    [Pg.296]    [Pg.49]    [Pg.167]    [Pg.177]    [Pg.356]    [Pg.25]    [Pg.91]    [Pg.190]    [Pg.108]    [Pg.35]    [Pg.30]    [Pg.85]    [Pg.266]    [Pg.60]    [Pg.61]    [Pg.126]    [Pg.420]    [Pg.103]    [Pg.153]    [Pg.255]    [Pg.7]    [Pg.73]    [Pg.358]    [Pg.19]    [Pg.54]   
See also in sourсe #XX -- [ Pg.175 , Pg.182 , Pg.183 ]




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Function information

Missing information

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