Constraints definition

Packaging, Handling, Storage, and Transportation System Dimensional Constraints, Definition of , Ml L-STD-1306 (1972) 24) Anon,... 

Constraints, Definition, Classification Equality and Inequality Constraints Based on Chemical or... 

Mineral polymorphs of this type are the usual sort of geochemical examples used to define metastable equilibria, and the usual definition centers on the fact that the metastable phase has a higher energy content than the stable phase. By focusing on the constraint that prevents the metastable phase from changing to the stable phase, we have not changed the concept of metastability but have simply broadened its applicability, as shown in the other examples. The perfect analogy between the partitioned gas example and the polymorph example should demonstrate the utility of the extra constraint definition we have used. 

Every information system, and therefore specification, must recognise and support tlie business rules tliat govern tlie application. Tliese rules control the operation of the system ( when tilings happen ). Business rules, or constraints, are vitally important not only to the successfiil deployment of tlie system but also to tlie success of the enterprise tliey must therefore be included in every information system specification. The notion of function is prerequisite to the notion of , since an operation (function) is a necessary component of a constraint definition the notion of concept is doubly prerequisite to the notion of , since a constraint is a relationship between two different concepts. 

Type definitions II Constant definitions II Function definitions II Constraint definitions // System definitions II Property definitions... 

Constraint definition Here the steric and/or chemical constraints of the design problem are delineated and supplied to the program in an appropriate form. In many cases these constraints will be derived from the active site (or, more generally, receptor site) derived from homology models, receptor models, - pharmacophore models, CoMFA models, or just a single molecule may also be used. 

The third stage is constraints definition and financial resources seem to be the most often... 

Electrochemical cells may be used in either active or passive modes, depending on whether or not a signal, typically a current or voltage, must be actively appHed to the cell in order to evoke an analytically usehil response. Electroanalytical techniques have also been divided into two broad categories, static and dynamic, depending on whether or not current dows in the external circuit (1). In the static case, the system is assumed to be at equilibrium. The term dynamic indicates that the system has been disturbed and is not at equilibrium when the measurement is made. These definitions are often inappropriate because active measurements can be made that hardly disturb the system and passive measurements can be made on systems that are far from equilibrium. The terms static and dynamic also imply some sort of artificial time constraints on the measurement. Active and passive are terms that nonelectrochemists seem to understand more readily than static and dynamic. 

No single method or algorithm of optimization exists that can be apphed efficiently to all problems. The method chosen for any particular case will depend primarily on (I) the character of the objective function, (2) the nature of the constraints, and (3) the number of independent and dependent variables. Table 8-6 summarizes the six general steps for the analysis and solution of optimization problems (Edgar and Himmelblau, Optimization of Chemical Processes, McGraw-HiU, New York, 1988). You do not have to follow the cited order exac tly, but vou should cover all of the steps eventually. Shortcuts in the procedure are allowable, and the easy steps can be performed first. Steps I, 2, and 3 deal with the mathematical definition of the problem ideutificatiou of variables and specification of the objective function and statement of the constraints. If the process to be optimized is very complex, it may be necessaiy to reformulate the problem so that it can be solved with reasonable effort. Later in this section, we discuss the development of mathematical models for the process and the objec tive function (the economic model). 

The bilinear form in the argument of the exponential must be definite positive to have a well defined physics. This leads to constraints on the elements of the matrix A, as we shall see below. 

At a physical level. Equation 35 represents a mixing of all of the possible electronic states of the molecule, all of which have some probability of being attained according to the laws of quantum mechanics. Full Cl is the most complete non-relativistic treatment of the molecular system possible, within the limitations imposed by the chosen basis set. It represents the possible quantum states of the system while modelling the electron density in accordance with the definition (and constraints) of the basis set in use. For this reason, it appears in the rightmost column of the following methods chart ... 

Whereas the propagation of conditions through the modeling relationships always produces consistent completions in the definition of the initial state, this may not be true with the user-driven specifications. It is possible that a valve specified by the user to be OPEN, is found by the propagation of other conditions to be CLOSED. To detect such potential inconsistencies, we have developed a dependency network (Steele, 1980) to keep track of the flow of computations during constraint propagation. The dependency network is built on the undirected graph that represents the... 

Steele. G. L.. The Definition and Implementation of a Computer Programming Language Based On Constraints, AI Lab. Tech. Rep. AI-TR-595. Massachusetts Institute of Technology, Cambridge, MA, 1980. 

This first stage of the learning procedure is concluded with the definition of a set of constraints related to... 

By definition, the intrasituational variables must eventually be expressed in terms of the intersituational variables. It can be shown (Realff, 1992) that as long as we guarantee that the intersituational variables are at least as loosely constrained in x and y, the intrasituational variables will be, also. The final issue concerns intersituational variables that are constrained via an equality constraint. 

In these cases there is no well defined notion of a looser constraint, the choice is then either to force those variables to be equal in x and y, or to find some path from their value to a constraint on another inter- or intrasituational variable and thus be able to show that their values in jc, y should obey some ordering based on these other constraints. This topic is the subject of current research, but is not limiting in the flowshop example, since no such constraints exist. Lastly, it is not enough to assert conditions on the state variables in x and y, since we have made no reference to the discrete space of alternatives that the two solutions admit. Our definition of equivalence and dominance constrains us to have the same set of possible completions. For equivalence relationships the previous statement requires that the partial solutions, x and y, contain the same set of alphabet symbols, and for dominance relations the symbols of JC have to be equal to, or a subset of those of y. Thus our sufficient theory can be informally stated as follows ... 

The definition of the abstract form of the constraints between states must now be linked to the actual values of the variables in the constraints... 

According to Cano-Ruiz and McRae, process design as a part of process development starts with problem framing. At this stage, the concept definition, scope of analysis, design objectives, constraints, evaluation and interruption criteria have to be determined. They argued that framing decisions are often made implicitly, whereas the critical importance... 

Similar considerations were taken into account throughout the process of designing the study and committing the design to a protocol. In addition to analytical quality specifications, decisions were made regarding definitions of limits of detection and quantitation, levels of apparent residues at which confirmation was required, and how such confirmation would be achieved. All of these decisions were based on fulfilling the objectives of the study while operating within unavoidable time and resource constraints. 

The major routes of parenteral administration of drugs are subcutaneous, intramuscular, and intravenous. Other more specialized routes are intrathecal, in-tracistemal, intra-arterial, intraspinal, intraepidural, and intradermal. The intradermal route is not typically used to achieve systemic drug effects. The major routes will be discussed separately. Definitions of the more specialized routes, along with additional information concerning needle sizes, volumes typically administered, formulation constraints, and types of medication administered, are summarized in Table 1. 

One of the best definitions is by Attilio Bisio (1) The successful startup and operation of a commercial size unit whose design and operating procedures are in part based on experimentation and demonstration at a smaller scale of operation. He also points out that Smith (2) argued in 1968 that the starting point for scaleup studies is the ultimate intended commercial unit. The professional should scaledown from the design parameters and constraints of that commercial unit so that the smaller scale experiments were most useful in reducing the uncertainties of the commercial run. Smith wrote that scaleup from small-scale studies is a misleading concept. 

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