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Incomplete projections

Clearly, for a one-dimensional representation the character and the full matrix are the same thing. Hence, the incomplete projection operator is complete in these cases, and will provide the appropriate SALC unambiguously and automatically. Let us illustrate by asking what SALCs can be formed by the Is orbitals of the four hydrogen atoms in ethylene. [Pg.120]

Figure 3.2 A reconstruction from incomplete projections is a method where structure matrices and memory matrices are reconstructed in parallel. Figure 3.2 A reconstruction from incomplete projections is a method where structure matrices and memory matrices are reconstructed in parallel.
As we can see, the problem can be given a precise formulation, but what really counts is that it can also be given a solution. I have demonstrated that structures can indeed be reconstructed by using only 10% of the minimum number of projections (Barbieri, 1974a, 1974b, 1987), and an iterative algorithm which exploits memory matrices. More precisely, a reconstruction from incomplete projections is possible if two conditions are met (1) if the reconstruction method employs memory matrices where new information appears, and (2) if the reconstruction method employs codes, or conventions, which transfer information from the memory space to the real space. [Pg.205]

The algebraic methods of reconstruction give result at incomplete and complete set of initial projection data. But the iterative imhlementation of these methods requires large computing resources. Algebraic method can be used in cases, when the required accuracy is not great. [Pg.219]

If some fields may be empty in the sublevels, all the fields in the main level are required for each entry. A new chiral separation record can be added in CHIRBASE solely if the authors correctly identify both sample and CSP. Since the beginning of the project, our policy has been to contact the authors of all publications containing incomplete, ambiguous or inconsistent data and to ask for additional information. Providing the separations with unique case numbers helps us considerably in this essential task, and also facilitates avoiding redundancies in the database. When chiral separations are reported for the second time in a new publication with exactly the same chromatographic conditions, this is stated in a footnote added in the field comments . In this field, miscellaneous information that cannot appear elsewhere are listed (detection limit, description of a reported chromatogram, racemization study, mobile phase limitations, etc.). [Pg.98]

When synthesizing a flowsheet, these criteria are applied at various stages when the picture is still incomplete. Hence, it is usually not possible to account for all the fixed and variable costs listed above during the early stages of a project. Also, there is little point in calculating taxes until a complete picture of operating costs and cash flows has been established. [Pg.29]

The main tools used to provide global projections of future climate are general circulation models (GCMs). These are mathematical models based on fundamental physical laws and thus constitute dynamical representations of the climate system. Computational constraints impose a limitation on the resolution that it is possible to realise with such models, and so some unresolved processes are parameterised within the models. This includes many key processes that control climate sensitivity such as clouds, vegetation and oceanic convection [19] of which scientific understanding is still incomplete. [Pg.302]

One can identify two major categories of uncertainty in EIA data (scientific) uncertainty inherited in input data (e.g., incomplete or irrelevant baseline information, project characteristics, the misidentification of sources of impacts, as well as secondary, and cumulative impacts) and in impact prediction based on these data (lack of scientific evidence on the nature of affected objects and impacts, the misidentification of source-pathway-receptor relationships, model errors, misuse of proxy data from the analogous contexts) and decision (societal) uncertainty resulting from, e.g., inadequate scoping of impacts, imperfection of impact evaluation (e.g., insufficient provisions for public participation), human factor in formal decision-making (e.g., subjectivity, bias, any kind of pressure on a decision-maker), lack of strategic plans and policies and possible implications of nearby developments (Demidova, 2002). [Pg.21]

A complete and accurate site characterization provides the data to identify and design an appropriate remedial program. Poor or incomplete site characterization can lead to a problem project. [Pg.330]

In principle, a de novo protein structure determination requires one round of 7 Candid cycles. This is realistic for projects where an essentially complete chemical shift list is available and much effort was made to prepare a complete high-quality input of NOESY peak lists. In practice, it turned out to be more efficient to start a first round of Candid analysis without excessive work for the preparation of the input peak list, using an slightly incomplete list of safely identifiable NOESY cross peaks, and then to use the result of the first round of Candid assignment and structure determination as additional information from which to prepare an improved, more complete NOESY peak list as input for a second round of 7 Candid cycles. [Pg.63]

The documents were an incomplete subset of memoranda and reports from the MK-ULTRA program. They do include a description of some subsidiary projects, such as Bluebird, Artichoke and Derby Hat. In January, 1963 Gottlieb, at Helms direction, had already destroyed most of the other documents from the earlier CIA activities. Still others were withheld or heavily redacted. Those that remain refer to some of the experiments initiated in the 1950 s under the direction of Dr. Gottlieb. To me, they seemed scientifically imsophisticated and often done at the whim of the local agent in charge. [Pg.222]

Interest primarily in alternating projection methods has been sufficient to schedule a special Topical Meeting on Signal Recovery and Synthesis with Incomplete Information and Partial Constraints (Lake Tahoe, Nevada, January 12-14, 1983). [Pg.123]

We thank all the chapter authors for their heroic efforts in writting their chapters. Without their contributions this book would be incomplete. In addition, we thank Lloyd Goettler of Monsanto, who is past president of the Polymer Processing Society, for suggesting that we edit this book. Other friends and mentors who had a major influence on our work include Robert L. Kruse, Kishore Udipi, and Allen Padwa, all of Monsanto, and Professor John L. Kardos of Washington University. Professor Warren Baker, Series Editor, has been very helpful in overseeing this project. [Pg.19]


See other pages where Incomplete projections is mentioned: [Pg.53]    [Pg.115]    [Pg.118]    [Pg.115]    [Pg.118]    [Pg.67]    [Pg.69]    [Pg.71]    [Pg.71]    [Pg.84]    [Pg.86]    [Pg.53]    [Pg.115]    [Pg.118]    [Pg.115]    [Pg.118]    [Pg.67]    [Pg.69]    [Pg.71]    [Pg.71]    [Pg.84]    [Pg.86]    [Pg.2984]    [Pg.501]    [Pg.339]    [Pg.822]    [Pg.185]    [Pg.184]    [Pg.338]    [Pg.219]    [Pg.232]    [Pg.439]    [Pg.79]    [Pg.132]    [Pg.8]    [Pg.112]    [Pg.102]    [Pg.100]    [Pg.292]    [Pg.95]    [Pg.278]    [Pg.40]    [Pg.389]   
See also in sourсe #XX -- [ Pg.67 , Pg.69 , Pg.71 ]




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Incompleteness

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