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Linearized tree structure

A linear descriptor naturally contains an ordering of its elements, which makes it very easy to compare them. In a tree structure however, it is not clear which parts should be mapped onto each other. Different mappings will result in different similarity values ... [Pg.83]

The search for relationships among the dynamic and equilibrium properties of related series of compounds has been a paradigm of chemists for many years. The discovery of such unifying principles and predictive relationships has practical benefits. Numerous relationships exist among the structural characteristics, physicochemical properties, and/or biological qualities of classes of related compounds. Perhaps the best-known attribute relationships are the correlations between reaction rate constants and equilibrium constants for related reactions commonly known as linear tree-energy relationships (LFERs). The LFER concept led to the broader concepts of QSARs, which seek to predict the environmental fate of related compounds based on correlations between their bioactivity or physicochemical properties and structural features. For example, therapeutic response, environmental fate, and toxicity of organic compounds have been correlated with... [Pg.134]

One of the most effective algorithms for these classes of network problems has been a specialized implementation of the simplex algorithm for linear programming. This type of approach uses special data structures to exploit the special properties of the network models and accelerate the steps of the simplex algorithm. For example, for these network flow models (and aU of the other related subclasses discussed in this chapter), the set of basic variables corresponds to a set of arcs that form a spanning tree for the underlying network. Computing such items as the current values for the dual multiphers is easily done with a specialized procedure that exploits the basis tree structure (Ahuja et al. 1993). [Pg.2574]

The use of hypertext in information science is superior to a traditional linear presentation. It relies on a tree structure. However, it has a serious drawback. Looking at a branch, we have no idea what it represents in the whole diagram, whether it is an important branch or a remote tiny one does it lead further to important parts of the book or it is just a dead end, and so on. At the same time, a glimpse at the TREE shows us that the thick trunk is the most important structure. But what do we mean by important At least two criteria may be used it is important for the... [Pg.1050]

Strings, linear lists with space markers added, are often used to give text depictions of trees. There are several ways to visually depict the hierarchical relationship expressed by tree structures nested parentheses, bar indentation, set inclusion, and decimal points—essentially the same device used when library contents are organized, for example, by the Dewey decimal system. All of these methods can be useful. The kind of information that can be stored by a tree data structure is both varied and often needed in practical situations. For example, a tree can describe the chapter outline of a book (Fig. 2a). On personal computers or web browsers, the starting location is called the root or home. It lists highest level information. [Pg.100]

Clarke LP, Kallergi M, Qian W et al (1994) Tree-structured non-linear filter and wavelet transform for microcalcification segmentation in digital mammography. Cancer Lett 77 173-181... [Pg.369]

Many methods for linear system analysis are based on explicit linear ODEs. Constrained linear systems have therefore to be reduced first to an explicit linear ODE. In Sec. 1.4 such a reduction was obtained for tree structured systems by formulating the system in relative coordinates. For general systems this reduction has to be performed numerically. The reduction to this so-called state space form will be the topic of the first part of this chapter. Then, the exact solution of linear ODEs and DAEs is discussed. [Pg.35]

Let Fo be the number of degrees of freedom of the tree-structure system, once the joints have been cut, and q the corresponding Foxl vector of joint coordinates. The components of q are not independent because they are related through the cut joint constraints. Let be the number of the degrees of freedom of the closed loop system and z the F(xl vector of independent joint coordinates. A linear relationship between the two sets of joint velocities must exist and can be written as... [Pg.23]

Models of the form y =f(x) or v =/(x1, x2,..., xm) can be linear or nonlinear they can be formulated as a relatively simple equation or can be implemented as a less evident algorithmic structure, for instance in artificial neural networks (ANN), tree-based methods (CART), local estimations of y by radial basis functions (RBF), k-NN like methods, or splines. This book focuses on linear models of the form... [Pg.118]

Fig. 17. Damping functions in shear from the tube model for linear polymers (lowest curve) and various branched architectures. In the cases of comb and tree, the lower curves give the case of the structure with four levels of branching, the upper the limit of large structures hatched area covers published results on LDPE... Fig. 17. Damping functions in shear from the tube model for linear polymers (lowest curve) and various branched architectures. In the cases of comb and tree, the lower curves give the case of the structure with four levels of branching, the upper the limit of large structures hatched area covers published results on LDPE...
Paper products (newsprint, tissue, packaging, etc.) are made from pulps that consist of natural fibers derived from vascular plants such as trees, sugar cane, bamboo, and grass. The vascular fiber walls are composed of bundles of cellulose polymeric filaments. This long, linear glucose polymer is what paper is made from. The polymer has the structure shown in Scheme 8.18. [Pg.428]


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