Design rules, example

More shortcut design methods and rules of thumb have been developed for fractionation than probably any other unit operation. For example the paper reprinted in Appendix 5 on development of shortcut equipment design methods contains 18 references for fractionation shortcut methods out of 37 total. Both the process and mechanical aspects of fractionation design have useful rules of thumb. Many of the mechanical design rules of thumb become included in checklists of do s and don ts. 

Protocol rules, also known as business rules, are the rules that reflect the trial design. For examples, a protocol rule states that up to 99 interim visits can be scheduled between two protocol visits, visits may occur before or after their expected dates given a predefined leeway, and if the trial has multiple... 

We will first discuss some examples of biocatalytic polymerisation in biological systems, followed by a review of recent man-made systems and the design rules that are emerging. Unique features related to control of polymerisation (both in terms of kinetics and thermodynamics) will be discussed, followed by a review of (potential) applications in biomedicine and nanotechnology. 

Ryadnov et al. (2003) have designed a coiled coil-based nanoscale linker system dubbed Belt-and-Braces. The system was novel in a number of respects. Though based on a leucine-zipper dimer design, it was a ternary system in which one peptide (the Belt ) templated the assembly of two half-sized peptides (the Braces ) thus, the system was the first and simplest example of a coiled-coil vernier assembly (Kelly et al., 1998). The Belt-and-Braces design employed all of the key design rules for a... 

Using these results Van de Velden et al. (2008) were able to recommend design rules for operation of such reactors in terms of the gas velocity/solids loading parameters. For example, to ensure a narrow residence time distribution (operating, in effect, in plug flow), the superficial gas velocity should exceed the transport velocity by approximately lm/s and the solids circulation rate should exceed 200kg/m2s. 

When design rules invade the sub-micron regime, new process problems will occur. These problems are partly caused by the increased aspect ratios which are inherent to sub-micron design rules. For example, low temperature oxides such as SiH4/02-LT0 or plasma enhanced Si3N4... 

Many design rules from various groups have been created to optimize the specificity of a siRNA molecule (fig. 9.2). Many of these rules have evolved as the RNAi technology has become more prevalent in mRNA expression studies. How an siRNA duplex sequence is related to its target mRNA sequence can be illustrated with an example target region from Lamin A/C [7]. 

Very quickly the number of describable and designable structures expands. It would be injudicious for us to attempt to cover the myriad of possible structures, as the design rules should be transparent and easily applied by anyone who has followed our discussion up to this point. For esthetic reasons, however, we would like to point out some signal examples of molecules that fall into this expanded regime. 

Users will quickly construct mental rules as they operate the systan for the first time. The assimilated rules empower than to go on to proficiently operate unfamiliar parts of the appUcation using the conventions learned in more accustomed areas. To achieve this designers need to strive for consistency in user interface design. For example, if some screens contain buttons labelled Save and Close whilst others have Okay and Cancel for the same functions, this is likely to prove confusing and hinder rule development In fact one of the least technically challenging enhancements to a user interface is to simply ensure that material is labelled appropriately, that abbreviations and ambiguities are avoided and button captions reflect their true function. 

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