Reverse engineering scale

The work of Carnot, published in 1824, and later the work of Clausius (1850) and Kelvin (1851), advanced the formulation of the properties of entropy and temperature and the second law. Clausius introduced the word entropy in 1865. The first law expresses the qualitative equivalence of heat and work as well as the conservation of energy. The second law is a qualitative statement on the accessibility of energy and the direction of progress of real processes. For example, the efficiency of a reversible engine is a function of temperature only, and efficiency cannot exceed unity. These statements are the results of the first and second laws, and can be used to define an absolute scale of temperature that is independent of ary material properties used to measure it. A quantitative description of the second law emerges by determining entropy and entropy production in irreversible processes. 

The classic definition of temperature is based upon thermodynamics. Any suitable relation, based on the laws of thermodynamics, can be used to describe temperature on a thermodynamic scale. The two most commonly used relations are the efficiency of the reversible engine (the Carnot cycle) and the intensity of blackbody radiation (Planck s Law) expressed mathematically by... 

Reverse engineering has been successfully applied to relatively simple biomolecular systems. Using a combination of cross-correlation analysis and multidimensional scaling, the glycolytic pathway was reconstructed from metabolite activity data from an in vitro enzymatic reactor system [21]. A complete spatio-temporal model of developmental gene expression in Drosophila was constructed for a small gene set based on models of differential equations and protein expression data [22],... 

For a reversible engine, both the efficiency and the ratio QJQi can be calculated directly from the measurable quantities of work and heat flowing to the surroundings. Therefore we have measurable properties that depend on temperatures only and are independent of the properties of any special kind of substance. Consequently, it is possible to establish a scale of temperature independent of the properties of any individual substance. This overcomes the difficulty associated with empirical scales of temperature described in Section 6.5. This scale is the absolute, or the thermodynamic, temperature scale. 

Since there is nothing special about the temperature of the cold reservoir, except that d > do, Eqs. (8.18) and (8.19) apply to any reversible heat engine operating between any two thermodynamic temperatures d and do - Equation (8.18) shows that the work produced in a reversible heat engine is directly proportional to the difference in temperatures on the thermodynamic scale, while the efficiency is equal to the ratio of the difference in temperature to the temperature of the hot reservoir. The Carnot formula, Eq. (8.19), which relates the efficiency of a reversible engine to the temperatures of the reservoirs is probably the most celebrated formula in all of thermodynamics. 

Lord Kelvin was the first to define the thermodynamic temperature scale, named in his honor, from the properties of reversible engines. If we choose the same size of the degree for both the Kelvin scale and the ideal gas scale, and adjust the proportionality constant a in Eq. (8.16) to conform to the ordinary definition of one mole of an ideal gas, then the... 

Extension of this self-assembly approach to supramolecular engineering has led to an alternate motif for noncovalent cross-linking, a series of bisthymines that are complementary to the diamidopyridine side chains of polymer 6 (33). Upon combination in non-polar media thermally reversible, micrometer scale spherical aggregates were formed (Figs. 13b and 13c). 

One can now define a temperature T =f t), based solely on the efficiencies of reversible heat engines. This is the absolute temperature measured in Kelvin. In terms of this temperature scale, the efficiency of a reversible engine is given by... 

Csete ME, Doyle JC (2002) Reverse engineering of biological complexity. Science 295 1664-1669 De Figueiredo LF, Podhorski A, Rubio A, Kaleta C, Beasley JE, Schuster S, Planes EJ (2009) Computing the shortest elementary flux modes in genome-scale metabolic networks. Bioinformatics 25 3158-3165... 

The introduction stated that the main contribution c this paper is to identify those features the Maintainer s Assistant that, fr( n practical experirace, are essential to the design oi a usable tool for transformation-based reverse engineering. The experience has bera gained by applying the tool to a series of real Assembler programs (not "toy" examples). Ibese Assembler programs are typical of heavily-maintained, unstructured, medium-scale programs (of up to 20,0(X> lines). 

The Maintainer s Assistant project has demonstrated that a tool to assist reverse engineering of sequential systons, based on formal transfcHmation systmns, is feasible for non trivial industrial scale problems. The tool has beat used with IBM 370 Assembler to date and while this is of minority interest, it is also an extrmely challenging example. We have demonstrated that a more comprehensible ft m of an existing heavily maintained program can be obtained relatively easily using the Maintainer s Assistant... 

Hardness is a measurement of material resistance to plastic deformation in most cases. It is a simple nondestructive technique to test material indentation resistance, scratch resistance, wear resistance, or machinability. Hardness testing can be conducted by various methods, and it has long been used in analyzing part mechanical properties. In reverse engineering, this test is also widely used to check the material heat treatment condition and strength, particularly for a noncritical part, to save costs. The hardness of a material is usually quantitatively represented by a hardness number in various scales. The most utilized scales are Brinell, Rockwell, and Vickers for bulk hardness measurements. Knoop, Vickers microhardness, and other microhardness scales are used for very small area hardness measurements. Rockwell superficial and Shore scleroscope tests are used for surface hardness measurements. Surface hardness can also be measured on a nanoscale today. 

Hardness provides a first order of approximation of mechanical strength. However, great caution is required to extrapolate mechanical properties directly from hardness. First, hardness is measured using a variety of scales, each representing different material characteristics, and there are no precise conversions among them. Second, the relationships, if any, between hardness and other mechanical properties are usually empirical and lack supporting scientific theories. These relationships are material specific with limited applicability. In reverse engineering, a hardness comparison should always be in the same scale whenever feasible. Conformance to a material specification based on hardness is an estimate at best. 

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