Exclusive OR function

Forcing Structures Consider the Boolean OR function. Note that the value of cti or CT2 is fixed as 1 whenever either a or C2 is equal to 1. Kauffman calls any function with the property that at least one value of at least one of its inputs fixes its output, a canalizing function [kauff84]. The Boolean functions OR and AND , for example, are both canalizing functions, but the EXCLUSIVE OR function is not. 

To see what we mean by linear separability, we consider a simple problem that is not linearly separable the so-called XOR problem - to teach a neural net the exclusive-OR function (table 10.2). 

When, say, infrared or mass spectra can be reduced to binary strings indicating the presence or absence of peaks or other features, the Hamming distance metric is simple to implement. In such cases it provides a value of differing bits in the binary pattern and is equivalent to performing the exclusive-OR function between the vectors. The Hamming distance is a popular choice in spectral... 

This particular function is called the exclusive OR function (XOR) and is the basis for binary arithmetic operations. It says that X is true if A or B, but not both, are true. It has a defining symbol and is written as... 

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. 

This model can be simplified by reducing it to a single parameter. Vichniac, et.al. [vich86b] for example, consider the behavior along the line p = 1 — Pi- They point out that this reduction affords pi and p2 a simple interpretation in terms of the familiar Boolean functions AND and XOR (exclusive OR). In particular, for the line p2 = 1 — pi, we can equate pi = p(XOR) and P2 = 1 — Pi = p(AND), so that... 

Consider the Boolean exclusive-OR (or XOR) function that we used as an example of a linearly inseparable problem in our discussion of simple perceptrons. In section 10.5.2 we saw that if a perceptron is limited to having only input and output layers (and no hidden layers), and is composed of binary threshold McCulloch-Pitts neurons, the value y of its lone output neuron is given by... 

Upper alimentary symptoms in the absence of a clear pathological cause are referred to as non-ulcer dyspepsia or functional dyspepsia. The diagnosis is, in essence, by exclusion. 

In general, peptides and protein drugs are almost exclusively eliminated by metabolism via the same catabolic pathways as endogenous or dietary proteins, resulting in amino acids that are reutilized in the endogenous amino acid pool for de-novo biosynthesis of structural or functional body proteins. This has, for example,... 

Furthermore, they demonstrated that monitoring porphyrin emission with 470 nm excitation could perform either NOT-OR (NOR) or exclusive OR (XOR) logic functions. Of course, the performances of the triad were investigated in liquid solution, which will pose major challenges for the technological application. 

The actual function of aconitic acid in the plant physiology is not clearly understood. Cis-aconitic acid undoubtedly is present to a certain extent in the plant because of its role in the citric acid cycle but the factors which cause the accumulation of comparatively large quantities of aconitic acid have not been clearly defined. Whether the concentration of aconitic acid which is formed in the plant is the cts-form exclusively or is a mixture of the cis- and the trans- acids is also unknown. Balch, Broeg and Ambler,37 in their investigations, reported considerable variation in the aconitic acid content of various crusher juices of Louisiana... 

The exclusion of certain test(s) or exploration(s) of certain organs, systems or functions however should be scientifically justified. 

S7A differentiates between 3 types of studies core battery, follow-up and supplemental studies. The core battery of tests/S7A consistes of an investigation of the effects of a test substance on vital functions central nervous system cardiovascular system respiratory system other systems as appropriate. The exclusion of a system or function should be justified. Safety Pharmacology studies carried out as necessary as ... 

Note that the physicochemical mechanisms that enables us to perform the chromatographic bioseparations are not always adsorption-like but can involve ion exchange, ion exclusion, or size exclusion. Even if it is generally possible to fit experimental data with a mathematical function derived from the adsorption theory, it is strongly advisable to refer to the proper physicochemical process before modeling the separation. For instance, ion exchange can be modeled with selectivity coefficients (derived from the mass action law) that can be constant or not,18,19 ion-exclusion can be modeled thanks to theories based on the Donnan exclusion, etc. 

Here is a model of a different simple arithmetic-logic-unit. This logic unit performs four functions add, nand, greater-than and exclusive-or. A continuous assignment statement with a conditional expression is used to model the arithmetic-logic-unit. 

Artificial neural networks (ANN s) were effectively set aside for 15 years after a 1969 study by Minksy and Papert demonstrated their failure to correctly model a simple exclusive OR (XOR) function. i The XOR function describes the result of an operation involving two bits (1 or 0). A simple OR function produces a value of 1 if either bit or both bits have a value of 1. The XOR differs from an OR function in the output of an operation on two bits of value 1. The XOR function will yield a 0 while the OR function will yield a 1. Interest in ANN s resumed in the 1980 s after modifications were made to the layering of their neurons that allowed them to overcome the XOR test as well as a wide variety of other non-linear modeling challenges. 

In the description of crystals and crystal structures the two terms/om and habit have very specific and very different meanings. Form refers to the internal crystal structure and etymologically is the descendant of the Greek morph. Hence, polymorph refers to a number of different crystal modifications or different crystal structures, and the naming of different structures as Form F or a Form follows directly from this definition and usage. As we have seen above, the difference in crystal structure is very much, although not exclusively, a function of thermodynamics. Certainly, only the structures which are thermodynamically accessible can ever exist, but there often is a question of thermodynamic vs kinetic control over which particular structure may be obtained under any particular set of crystal growth conditions. 

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