Universal/specific approach

Ko, C.C.W. Execution Monitoring of Security-Critical Programs in a Distributed System A Specification-Based Approach. PhD thesis. University of California (1996)... 

The premise of noncompartmental PK analysis is to utilize a universal approach to analyze plasma concentration data without making assumptions about a specific number of model compartments or type of absorption process. This generally involves fitting the measured plasma concentration data to an equation in the form of a sum of multiple exponential terms ... 

It shonld be noted that the problem of structural instability exists for all types of the above-mentioned structures independent of material nsed. Moreover, resolving this problem does not have a universal approach. Unfortnnately, every material used for mesoporous, macroporous, and hollow structure fabrication reqnires a specific approach for resolving it. For example, Shimizu and coworkers (Hyodo et al. 2002) found that the most important key to the drastic improvement of thermal stability of mesoporons (m-) SnO powders is to immerse them in a phosphoric acid aqneons solution before calcination and conseqnently loading phosphorus components on the snrface of m-SnO crystallites. Snch treatment enabled the preparation of the m-SnO powders with small crystalhte size (2-3 mn in diameter) and large specific surface area (>300 mVg) even after calcination at 600 °C. 

Partial specific volumes and other volume quantities have been determined experimentally, predominantly by density measurements. However, sometimes experimental determinations of volumes of both macromolecules and nonmacromolecular components are not feasible, e.g., due to insufficient amounts of material, lack of purity of samples, uncertainties in sample concentration, and handling problems such as instability of samples or adsorption phenomena. In these cases estimates can be obtained by calculations or reliable approximations. Though first attempts to calculate volumetric properties of organic compounds reach back to 1839 [1839K1], only recently a universal approach has been elaborated which allows ab initio calculations of partial volumes of small molecules and polymers of different chemical composition and structure in aqueous solution [94D1]. 

In order to do this, experimental determinations of the intrinsic viscosities of both the standards and the fractions from the unknown polymer are required. It is possible to obtain commercial gel permeation chromatographs that will do this routinely, and hence to exploit the concept of universal cali-hration. Care must he taken, though, to ensure that the separation of the polymer molecules occurs purely as a result of size exclusion. If there are any other specific interactions, e.g. hydrogen bonding, between the polymer and the column packing, such as may occur with water-soluhle polymers, Benoit s approach does not work and the universal cafihrafion plot is not valid. 

Komit6 for Levnedsmidler (NMKL)]. The standard presents a universal validation approach for chemical analytical methods in the food sector. This includes methods for the main constituents and also for trace components. Therefore, the NMKL procedure focuses on primary validation parameters, such as specificity, calibration, trueness, precision, LOD or LOQ and does not refer to special requirements of pesticide residue analysis. 

Quantitative XRF analysis has developed from specific to universal methods. At the time of poor computational facilities, methods were limited to the determination of few elements in well-defined concentration ranges by statistical treatment of experimental data from reference material (linear or second order curves), or by compensation methods (dilution, internal standards, etc.). Later, semi-empirical influence coefficient methods were introduced. Universality came about by the development of fundamental parameter approaches for the correction of total matrix effects... 

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