Subject performance characteristics

To avoid any subjectivity in the judgement of performance characteristics presented by applicants, the permitted ranges of several parameters are fixed (e.g., recovery, repeatability, highest intensity of blank signals compared with the LOQ). However, in other cases professional judgement of the referee is required to assess validation results. Some of these aspects are discussed below. 

Assessment ofphase diagrams. Selection, designing and planning of materials are relevant subjects from a fundamental point of view but, of course, are also interrelated basic topics in material science and engineering. Study and classification of preparation methods and of constitutional and fundamental properties followed by an investigation of application and performance characteristics are essential aspects of such topics and procedures. 

Full validation of an analytical method usually comprises an examination of its characteristics in interlaboratory method performance studies. However, before a method is subjected to validation by collaborative studies, the method must be validated by a single laboratory, usually by the laboratory that developed or modified this particular measurement procedure. Method validation can be described as the set of tests used to establish and document the performance characteristics of a method and against which it may be judged, thereby demonstrating that the method is fit for a particular analytical purpose. 

The operational characteristics such as depth resolution, maximum accessible depth and minimum detection limit in ERD are highly subjective to each experiment condition. In our system with the conditions described in the experimental procedures section and assuming Si as the primary matrix for the target, the typical performance characteristics in routine applications are 80-100 A depth resolution, 1 pm maximum depth and about 0.1 at.% minimum detection limit. For more discussion of operation characteristics one may refer to our earlier work (2). 

Apart from the frictional effects, two other performance characteristics need to be considered, namely load-carrying capacity and wear. Most of the available information on these subjects has been obtained from the practical use of commercial materials and will be discussed later, but Groszek and Witheridge found that molybdenum disulphide ground conventionally in air gave a small increase in Mean Hertz Load and Weld Load in a Four-Ball Test as 5% dispersions in a mineral oil. However, oleophilic molybdenum disulphide, ground in n-heptane, gave a 170% increase in Mean Hertz Load and a 260% increase in Weld Load. 

The subject of the secondary protein structure as a means of defining the performance characteristics ofwheat endosperm-known as hardness-been explored over a seven year period [39, 40]. Another approach, taken by Baron et al., involves the IMS imaging of the endosperm cell walls rather than of the protein found in the endosperm itself [61]. All of these authors performed the imaging in situ, following removal of the protein and starch, in order to study the compositional and architectural heterogeneity and, in relation to this, wheat hardness. In this case, the research was focused on kernel hardness rather than on endosperm hardness, as was the case with our studies. A further study of carbohydrate polymers by the same group involved the investigation of cereal arabinoxylans in relation to their structure and physico-chemical properties. 

Dual-task scenario A test paradigm characteristic by a primary and secondary task and measurement of subject performance in both. 

Not later than 30 months after October 28, 1992, the President shall, after notice and opportunity for comment, establish by rule appropriate criteria, testing protocols, and performance characteristics as are necessary to ensure, to the greatest extent possible and consistent with the purposes and policy of this subchapter, that lead-based paint hazard evaluation and reduction products introduced into commerce after a period specified in the rule are effective for the intended use described by the manufacturer. The rule shall identify the types or classes of products that are subject to such rule. The President, in implementation of the rule, shall, to the maximum extent possible, utilize independent testing laboratories, as appropriate, and consult with such entities and others in developing the rules. The President may delegate the authorities under this subsection to the Environmental Protection Agency or the Secretary of Commerce or such other appropriate agency. 

The procedure by which an emulsion polymerization is carried out has a profound effect upon the resulting latex and polymer properties. Indeed, latexes and polymers with quite different performance characteristics can be produced from the same reaction formulation by appropriate control of the type of polymerization process and conditions used. In this chapter, the two types of batchwise process are described with particular emphasis upon the control that can be exercised over polymerization conditions and product properties. An enormous volume of material on this subject exists in the scientific and patent literature, and cannot be fully documented here. Instead, general principles are presented and illustrated using specific examples which serve as good starting points for researching relevant literature on the topics covered. 

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