Output Boolean

The Web-based graphical user interface permits a choice from numerous criteria and the performance of rapid searches. This service, based on the chemistry information toolkit CACTVS, provides complex Boolean searches. Flexible substructure searches have also been implemented. Users can conduct 3D pharmacophore queries in up to 25 conformations pre-calculated for each compound. Numerous output formats as well as 2D and 3D visuaHzation options are supplied. It is possible to export search results in various forms and with choices for data contents in the exported files, for structure sets ranging in size from a single compound to the entire database. Additional information and down-loadable files (in various formats) can be obtained from this service. 

Input/Output statements—Two boolean functions that are useful in input processing are EOF, which is TRUE if the pointer is currently at the end of the input file and FALSE otherwise, and EOLN, which is TRUE if the pointer is at the end of the current input line and FALSE otherwise. 

In this case, each site can have many identical outputs but receives only a single input. There are four possible Boolean functions with one input two yield fixed values of 0 or 1, independent of input (these two static functions, and Fi are always among the 2 possible Boolean functions), the third inverts the input T = —) and the fourth is the identity = +). We will discuss behavior arising only ft om the latter two active functions. Exact results for the analytically tractable case of allowing a distribution of all four Boolean functions have been derived by Flyvbjerg and Kjaer [flyvb88]. 

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. 

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... 

We have seen that the output neuron in a binary-threshold perceptron without hidden layers can only specify on which side of a particular hyperplane the input lies. Its decision region consists simply of a half-plane bounded by a hyperplane. If one hidden layer is added, however, the neurons in the hidden layer effectively take an intersection (i.e. a Boolean AND operation) of the half-planes formed by the input neurons and can thus form arbitrary (possible unbounded) convex regions. ... 

Boolean OR operation will be performed if the synaptic weights between the second hidden layer and the output layer are equal to one and the output neuron s thresholds are set to 0.5 [lipp87]. 

Writing a specification for an operation is very different from writing an implementation. The spec is simply a Boolean expression a relation between the inputs, initial state, final state, and outputs. An implementation would choose a particular algorithmic sequence of steps, select a data representation or specific internal access functions, and work through iterations, branches, and many intermediate states before achieving the final state. Consider the specifications of these operations in contrast to their possible implementations ... 

Standard Boolean processing of Boolean properties outputs are true when their inputs have the relationship marked. (The symbols come from the tradition of electronic logic.)... 

Components are instantiated in the same way as types are instantiated in a postcondition by using ComponentType.new. Consider an operation that causes a component to permanently invert the value of a Boolean output property. 

The CD-ROM version of the data base can be efficiently searched with a menu-driven type of software called Search Express. It allows one to search with Boolean expressions as well as individual words and/or frequency of hits as a function of the number of documents retrieved on a given topic. Numerous searchable fields have been included, allowing one to retrieve information by a variety of means, for example, the compound name the chemical registry number, the amount of material released into the air, water, or land the location of the site of release and the SIC code of the releasing party. One can also employ ranging methods with available numeric fields and sorting of output. 

Once an output set has been established, the direction of information flow is fixed in the system of equations, and they can be represented either by a linear diagraph or its associated Boolean adjacency matrix. For our purposes it is more convenient to work with the Boolean adjacency matrix, which can be obtained directly from the occurrence matrix and output set as follows. First, assign numbers to the equations that correspond to the rows, and numbers to the variables that correspond to the columns of the occurrence matrix as in Fig. 5. Then pick an output set by the methods described in Section III. For the first equation, and the number of the column containing its output variable. The information flow transmitted by the variable designated by the column number goes to all other equations that have nonzero... 

The LINEST function requires four arguments, the locations of the cells that contain the activity (y-data), the cells with the parameter values (x-data), a boolean variable for requesting calculation of a y-intercept, and a boolean variable for requesting statistical output (Figure B.2). The exact syntax of the LINEST function depends on the software package. 

EMBL Nucleotide Sequence Database. SWISS-PROT consists of core sequence data with minimal redundancy, citation and extensive annotations including protein function, post-translational modifications, domain sites, protein structural information, diseases associated with protein deficiencies and variants. SWISS-PROT and TrEMBL are available at EBI site, http //www.ebi.ac.uk/swissprot/, and ExPASy site, http //www.expasy.ch/sprot/. From the SWISS-PROT and TrEMBL page of ExPASy site, click Full text search (under Access to SWISS-PROT and TrEMBL) to open the search page (Figure 11.3). Enter the keyword string (use Boolean expression if required), check SWISS-PROT box, and click the Submit button. Select the desired entry from the returned list to view the annotated sequence data in Swiss-Prot format. An output in the fasta format can be requested. Links to BLAST, feature table, some ExPASy proteomic tools (e.g., Compute pI/Mw, ProtParam, ProfileScan, ProtScale, PeptideMass, ScanProsite), and structure (SWISS-MODEL) are provided on the page. 

Outputs. Every user who took part in an initialization obtains an output denoting the success of this initialization. Sometimes this output is only Boolean. In other cases, it must denote which potential recipients took part successfully. To cover all cases, a value acc with a domain Init results 3 TRUE, FALSE and an additional parameter ids f are provided. The meaning of acc = TRUE is basically that the signer behaved correctly and can now sign, and ids f denotes those recipients and courts that can now test and decide. 

Thus a transfer is defined by the following interface events The first recipient inputs show m, id, i), and the second recipient inputs test(m, id, 0 and obtains a Boolean output acc. The first recipient also obtains an output, usually eot . 

V, the verifier s algorithm, is a probabilistic interactive algorithm with one input-output port. Its initial input is a pair (par, K) with par as above, and it outputs a Boolean value acc. It has to work in time polynomial in the input par alone. (Hence it is polynomial-time when regarded as an interactive algorithm where only par is the initial input and K may be sent by the attacker.)... 

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