System function definition

From a reliability engineering perspective, error can be defined by analogy with hardware reliability as "The likelihood that the human fails to provide a required system function when called upon to provide that fimction, within a required time period" (Meister, 1966). This definition does not contain any references to why the error occurred, but instead focuses on the consequences of the error for the system (loss or unavailability of a required function). The disadvantage of such a definition is that it fails to consider the wide range of other actions that the human might make, which may have other safety implications for the system, as well as not achieving the required function. 

Human Error Probability The probability that an error will occur during the performance of a particular job or task within a defined time period. Alternative definition The probability that the human operator will fail to provide the required system function within the required time. 

The practices contained in this section apply to Standard Software Packages (e.g., spreadsheets, text processors, database programs, CAD systems, graphics packages, and programs for technical or scientific functions) that are considered part of a computer system. By definition, this includes noncustomized application software that has been purchased and that has not been modified. 

What if you are implementing a commercially available application (commercial off-the-shelf, or COTS application) rather than designing a custom application Do you still need these documents Yes, but probably not all of them. The FDA has made it clear [3] that URS are expected, even for COTS applications. Without a URS, there wouldbe no definition or required system functionality on which to base initial validation activities. The COTS URS will typically end up as a blend of the URS and FRS, as described previously. This blend of requirement types is appropriate for the COTS situation, in which you are specifying what is necessary for your business operations but do not need to write specifications sufficient to actually design the application from scratch. After selection of the application, additional specification... 

Speciation can be defined functionally, operationally, or chemically. A functional definition is one which specifies the type of role that the element may play in the system from which the sample was taken. For instance, a functional definition might be that mercury which can be taken up by plants or iron that can be absorbed from a pharmaceutical. This definition is probably closest to what the end user of the information really wants to know but is the most difficult for the analytical chemist to determine. Other than growing the plant in the contaminated water or soil sample and analyzing the plant tissue, or doing feeding studies on the pharmaceutical, it is nearly impossible to obtain this information experimentally. 

The photoreceptors of vision are not broadband detectors in the normal sense. They are sensitive to a range of considerably less than 2 1 compared to many metallic semiconductors and many radio antenna systems which are sensitive to ranges of 10 1 to 20 1 or more. Even in these systems, the definition of quality is usually taken as the coefficient of absorption as a function of wavelength (which is usually independent of the number of quanta incident), not how many quanta are absorbed per unit wavelength. 

Mathematical optimization deals with determining values for a set of unknown variables x, X2, , x , which best satisfy (optimize) some mathematical objective quantified by a scalar function of the unknown variables, F(xi, X2, , xn). The function F is termed the objective function bounds on the variables, along with mathematical dependencies between them, are termed constraints. Constraint-based analysis of metabolic systems requires definition of the constraints acting on biochemical variables (fluxes, concentrations, enzyme activities) and determining appropriate objective functions useful in determining the behavior of metabolic systems. 

All this is in contradiction to the density functional definition of electronegativity as presented originally by Parr[36], where it is also inferred that the electronegativity for all the (natural) orbitals of the system should be the same. The discrepancy between these two different derivations and points of view[29,36] is still to be resolved. In addition, the global definition of electronegativity as promulgated within density functional theory, does not appear to be particularly useful, as it yields the same... 

The first step in the evaluation process is to define and document the current system use and user requirement specifications. If the system will be changed in the foreseeable future, any resulting changes in the intended use of the system should be described as well. The definition should include a list of system functions, operational parameters and performance limits. For chromatography software required functions may include instrument control, data acquisition, peak integration through quantitation, file storage and retrieval and print-out of methods and data. If the system also includes spectrophotometric detectors, the functions for spectral evaluation should be specified as well. Table 2 lists items that should be included in the system documentation. 

In electron transfer the precursor complex may be regarded as the initial and the successor complex as the final state of the system. This definition allows for the development of a common formalism for describing both bi- and intramolecular electron-transfer processes. If > /2 and are the electronic wave functions of the separated reactants, and the interaction between the reactants is not large, then /, the wave function of the system in its initial state, is equal to and the potential energy... 

Parameter data entries on these templates are coupled with reference number entries. In situations where data source referencing is required, the reference system allows definition of the source for each parameter value. This feature is activated by a function key and allows the user to enter short references or footnotes. These references can be created, modified, printed, and searched by reference number. 

Load the configuration file dsweep.cfg. Open the spin system file (Edit Spin system...) and note the spin system variable definition. Examine the pulse sequence (Edit Pulse program...) and note the additional loop command to increment the chemical shift. Using the GolRun Experiment command simulate the spectrum which corresponds to the excitation profile of a 90° TOPHAT pulse. In 1D WIN-NMR process the FID using zero filling of Sl(r+i) 32/cand an exponential window function with a LB value of 2 Hz. 

By exchange, we mean the density functional definition of exchange, in which the wavefunction is a Slater determinant whose density is the exact density of the interacting system, and which minimizes the energy of the non-interacting system in the Kohn-Sham external potential, iv,a=o- Another useful concept is the pair distribution function, defined as[14]... 

These practices prove that dejure the mental hospital system functions as an arm of the medical profession, but de facto it functions as arm of the states law-enforcement system. Accordingly, I maintain that standard psychiatric practices do not represent the abuses of psychiatry on the contrary, they represent its "proper uses, sanctioned by tradition, science, medicine, law, custom, and common sense. The very definition of the word certifiable supports this interpretation of the psychiatrists role formerly called alienist, his job was, and is, to alienate, that is, remove, the subject from society Webster s defines certifiable as fit to be certified as insane, befitting an insane person. ... 

The areas covered by this chapter deal with the photochemistry and radiation chemistry of triply bonded systems. The definition of a system with a triple bond is fairly loose and the review will deal with compounds which contain the following functionalities alkynes, nitriles, diazo compounds, diazonium salts and azides. The photochemical reactivity of these compounds has been reviewed extensively This review is not intended to be encyclopaedic but will highlight some of the areas currently of interest. 

The word orbital is usually taken to mean the solution of the Schrodinger equation for a one-particle system . This definition in practice is, then, limited to functions which are solutions of the Schrodinger equation for ... 

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