Tolerance modeling

Figure 2.2 (a) Tolerance versus production costs of various processes (b) comparison of cost-tolerance models (Dong, 1993)... 

The choice of tolerance model must be both realistic and applicable as a design tool... 

The role of advanced statistical and optimization methods in the tolerance model... 

Sufficient data on process distributions and costs must be collated to characterize manufacturing processes for advanced tolerance models. 

Research looking into tolerance allocation in assembly stacks is by no means new. A current theme is towards an optimization approach using complex routines and/ or cost models (Lin et al., 1997 Jeang, 1995). Advanced methods are also available, such as Monte Carlo Simulation and Method of Moment. ) (Chase and Parkinson, 1991 Wu et al., 1988). The approach presented here is based on empirical process capability measures using simple tolerance models, cost analogies and optimization... 

Keywords genetic engineering, genetic diversity, heavy metals, metal accumulation, metal tolerance, model plants, organic contaminants, quantitative trait loei... 

Gardmark M, Brynne L, Hammarlund-Udenaes M, Karlsson MO. Interchangeability and predictive performance of empirical tolerance models. Clin Pharma-cokinet 1999 36 145-67. 

Tolerance Model For some drugs, pharmacodynamic parameters like max and ECsn may appear to vary over time, resulting in changes in pharmacological response despite the presence of constant concentrations at the effect site. Tolerance is characterized by a reduction in pharmacological response after repeated or continuous drug exposure. The complex mechanism of tolerance may involve receptor pool depletion, decrease in receptor affinity, and up- or down-regulation. 

The mathematical distinctions between various models provide insight into differentiating between underlying mechanisms of tolerance. For example, some models of tolerance predict identical onset and recovery rates (61-64), while other models predict asymmetrical onset and recovery rates (65-70). For a more complete comparison of tolerance models, the reader is directed to Gardmark et al. (71). 

FIGURE 20.9 This tolerance model utilizes a hypothetical compartment (Tol) to measure the amount of tolerance in the system. Tol can act as a competitive or noncompetitive antagonist to the effect. The rate of tolerance development and recovery is determined by kjoi and the effect model is direct. A biophase compartment, Q, could have also been added (see Figure 20.10). (Adapted from Refs. 61 and 62.)... 

This convolution-based PD tolerance model has the following properties ... 

Imoto, S., Higuchi, T., Goto, T., and Miyano, S. (2006). Error tolerant model for incorporating biological knowledge with expression data in estimating gene networks. Stat. Methodoi, 3 1 -16. 

Tolerance Representation To be coherent, the tolerancing process has to use the same language based on a unified mathematical model to express tolerancing for each person involved during the process. To ensure this coherence between tolerance design and tolerance verification, there is a necessity of developing a complete tolerance model which should ... 

Geometric tolerances are also used in design to limit the form deviations. Classical tolerance models are not yet satisfactory in simulating the effect of the form deviations on part geometry. The modal tolerancing method allows to decompose any real defects of any discretized feature in the natural mode shapes with an unambiguous mathematical language. The finite element method is used to compute those shapes, and... 

A tolerance model includes 2D or 3D contours or wires with constrained chains of dimensions and tolerance values. It relates... 

Annotating drawings extracted from the tolerance model. Syntactically correct tolerance description for documentation. 

Ocampo-Martinez, C., Puig, V. (2009). Faul-tolerant model predictive control within the hybrid systems framework application to sewer networks. International Journal of Adaptive Control andSigrud Processing., 25(8), 757-787. 

Perception is easy—perhaps so easy we have a hard time finding words or formulas to describe the complicated appearance of objects. Many excellent scientific articles on the subject of metamerism appear each year in color literature (105) but even commonly accepted color tolerance models to which they refer are still under fire (106) (see Fig. 11). 

---