Experimental designs, descriptions

All requirements described in the MDR are considered during method development. Either an intuitive or an experimental design approach may be applied when optimizing methods, resulting in an optimal separation of the main compound and all relevant impurities in a reasonable analysis time using typical CE conditions. The development activities are mainly performed by the AD lab (Method Development Phase). Before submitting the method it should be evaluated for robustness and daily lab-to-lab application performance (Method Evaluation Phase). Is the method doable in all the application labs Is the method description acceptable Are all customer needs accounted for ... 

Lund, R.E. (1982b), Description and Evaluation of a Nested Cube Experimental Design, Commun. Statist.-Theor. Meth., 11, 2297-2313. 

The scope of this chapter is devoted to solving Eq. (2) and the implications that thereby arise. Accordingly, a description of the physical system is presented (Section 4.2), experimental design is discussed at length (Section 4.3), data pre-processing is addressed (Section 4.4) the current status of pure component spectral recovery is reviewed along with the salient mathematical issues (Section 4.5), and future directions are indicated (Section 4.6). 

A description of the experimental design, including the methods for the control of bias. 

Optimal design theory provides an alternative approach to the selection of an experimental design. For a description of the theory of optimal design see, for example, Atkinson and Donev [22]. 

Many developments have been made in the use of statistics to aid in experimental design over the last decades. The most important aspect of experimental design methods is that they provide a mathematical framework for changing all pertinent factors simultaneously, and achieve this in a small number of experiments. The description of such methods, though, is beyond the scope of this book and the reader is referred to the literature (Box et al., 1978 Bayne and Rubin, 1986 Haaland, 1989 Morgan, 1991) or to the internet for the latest design software (e. g. StatSoft, 1999). 

This chapter constitutes an attempt to demonstrate the utility of multivariate statistics in several stages of the scientific process. As a provocation, it is suggested that the multivariate approach (in experimental design, in data description and in data analysis) will always be more informative and make generalizations more valid than the univariate approach. Finally, the multivariate strategy can be really enjoyable, not the least for its capacity to reveal hidden treasures in data that in a univariate analysis look like a set of random numbers. 

The effects of interference on the flame photometric determination of potassium and sodium can be detected. Quantitative description of these interference effects is possible by empirical modeling on the basis of experimental design, i.e. by applying a multifactorial plan. 

No acute-, intermediate-, or chronic-duration inhalation MRLs were derived for barium because studies evaluating the effects of barium in humans and animals following acute, intermediate, and chronic inhalation exposure were inadequate for establishing the exposure concentrations associated with adverse health effects. The human studies (Doig 1976 Essing et al. 1976 Seaton et al. 1986 Shankle and Keane 1988) were limited by the small number of subjects and the lack of quantitative exposure information. The animal studies (Hicks et al. 1986 Tarasenko et al. 1977) were limited by inadequate descriptions of the experimental design. 

Detailed information on the experimental design, including a description of the chronologic study procedure, all methods, materials and conditions, type and frequency of analysis, measurements, observations, and examinations to be performed, and statistical methods to be used (if any). 

The Boltzmann law computes to a configurational AS governed by Eq. (3.22). A configurational AS represents dissolution of a perfectly ordered, pure solid polymer in pure solvent (Allcock and Lampe, 1981). van Oss (1991) cautions against designating physical processes as AH- or AS-driven unless careful microcalorimetric measurements have been made, because many thermodynamic suppositions (imputed to modeling or intuition) have not been substantiated by experimentation. Although descriptive analyses of... 

There are two competing and equivalent nomenclature systems encountered in the chemical literature. The description of data in terms of ways is derived from the statistical literature. Here a way is constituted by each independent, nontrivial factor that is manipulated with the data collection system. To continue with the example of excitation-emission matrix fluorescence spectra, the three-way data is constructed by manipulating the excitation-way, emission-way, and the sample-way for multiple samples. Implicit in this definition is a fully blocked experimental design where the collected data forms a cube with no missing values. Equivalently, hyphenated data is often referred to in terms of orders as derived from the mathematical literature. In tensor notation, a scalar is a zeroth-order tensor, a vector is first order, a matrix is second order, a cube is third order, etc. Hence, the collection of excitation-emission data discussed previously would form a third-order tensor. However, it should be mentioned that the way-based and order-based nomenclature are not directly interchangeable. By convention, order notation is based on the structure of the data collected from each sample. Analysis of collected excitation-emission fluorescence, forming a second-order tensor of data per sample, is referred to as second-order analysis, as compared with the three-way analysis just described. In this chapter, the way-based notation will be arbitrarily adopted to be consistent with previous work. 

The following discussion will assume that sufficient sample is available on which to undertake a complete structure proof. However, in the case of an investigation utilizing membranes, it obviously will be necessary to modify the experimental design to accommodate to the size of the sample. A description of suggested experimental approaches will be discussed and while the importance of certain procedures will be stressed, it will be up to the investigator to decide on the modus operandi based on sample size. 

Description of the hydrodynamics in the cylindrical capillary experimental design is fairly simple. Considering only electrostatic and fluid frictional forces acting upon the suspended particles, apparent particle mobility at a given location r across the diameter of the capillary may be represented by a solution to the Navier-Stokes equation in the scheme of a coordinate system with the origin in the center of the capillary by... 

Recordkeeping is essential and it begins with a protocol that delineates the objectives of the study and outlines the experimental design and methods. To comply with the GLP requirements, the final test report on the toxicological effects of the test chemical substance includes specific descriptions. These may be listed as ... 

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