Open concepts

The process of classification is typically based on systematically arranging entities on the basis of their similarities and differences. A bowl of fruit can be systematically arranged to have apples on one side and bananas on the other. Chemical elements can be systematically arranged into distinct families on the basis of their atomic structures. Classification of this sort is relatively easy and can be grounded on any number of relatively distinctive parameters or combinations of parameters, including color, size, shape, structure, taste, and so forth. We have already noted that psychiatric disorders are best characterized as open concepts. In open psychiatric concepts, overt, objective, and distinctive parameters are often less apparent, making their classification considerably more difficult. 

Evaluation of the concept of mental illness suggests that there are other aspects of its definition that create variability. Lilienfeld and Marino (1995) stated that there has always been great difficulty in establishing the boundary between mental illness and normalcy. These authors suggested that we need to accept this fuzzy boundary as a necessary condition of mental illness. They argued that mental illnesses should be considered open concepts (Meehl, 1977) or Roschian concepts (Rosch, 1973). A Roschian concept is essentially the same as the open concept we have already defined. It is a mental construction used to categorize natural entities that are characterized by fuzzy boundaries. Lilienfeld and Marino argued that this conception of... 

Perhaps it is time to move beyond simple description to start making explicit inferences, build and test theoretical connections, and advance our understanding of psychiatric open concepts until we achieve the closure. Arguably, we should start with inferences about relationships between DSM diagnoses and objective reality (i.e., whether diagnosis x refers to a natural category or not). 

Meehl, P. E. (1986). Diagnostic taxa as open concepts Meta-theoretical and statistical questions about reliability and construct validity in the grand strategy of nosological revision. In T. Millon G. L. Klerman (Eds.), Contemporary directions in psychopathology Toward the DSM-IV (pp. 215-231). New York Guilford. 

While Brower s open concept of version may be too wide for the purpose of the present study (allusions, for instance, will not be considered as forms of translation), his inclusion of varying degrees of... 

The cold runner head is installed with LSR moulds with several cavities. This eold runner head is mounted as a forward unit on the eylinder. Through maehine eontact, the head enters the mould through the fixed mould platen so diat the nozzle tips reaeh the eavities. Because of the open concept and modular constmction design, application of the head is flexible, and it may be fitted with up to six nozzles. Reducing or adding to the number of nozzles is simple and easy to perform with the use of blank adapters. Set-up and assembly on the machine are similar to a special nozzle so that installation work on the mould is eliminated. Figure 7.17 illustrates an installed cold ruimer head. 

It is remarkable that chemists long resisted making the connection between boron and electron-deficient carbon, which, after all, are analogs. I was thus given the opportunity to be able to establish the general concept of five and six coordination of electron-deficient carbon and to open up the field of what I called hypercarbon chemistry. 

Recovery methods are based either on mining combined with some further processing or operation on the oil sands m situ (Fig. 6). The mining methods are appHcable to shallow deposits, characterized by an overburden ratio (ie, overburden depth-to-thickness of tar sand deposit) of ca 1.0. Because Athabasca tar sands have a maximum thickness of ca 90 m and average ca 45 m, there are indications that no more than 10% of the in-place deposit is mineable within 1990s concepts of the economics and technology of open-pit mining. 

The evolution of T, is just an exercise in mesoscale thermodynamics [13]. These expressions, in combination with (7.54), incorporate concepts of heterogeneous deformation into a eonsistent mierostruetural model. Aspects of local material response under extremely rapid heating and cooling rates are still open to question. An important contribution to the micromechanical basis for heterogeneous deformation would certainly be to establish appropriate laws of flow-stress evolution due to rapid thermal cycling that would provide a physical basis for (7.54). 

Let us now look at the c.p.h. unit cell as shown in Fig. 5.4. A view looking down the vertical axis reveals the ABA stacking of close-packed planes. We build up our c.p.h. crystal by adding hexagonal building blocks to one another hexagonal blocks also stack so that they fill space. Here, again, we can use the unit cell concept to open up views of the various types of planes. 

This formula is another variation on the Affinity Laws. Monsieur s Darcy and VVeisbach were hydraulic civil engineers in France in the mid 1850s (some 50 years before Mr. H VV). They based their formulas on friction losses of water moving in open canals. They applied other friction coefficients from some private experimentation, and developed their formulas for friction losses in closed aqueduct tubes. Through the years, their coefficients have evolved to incorporate the concepts of laminar and turbulent flow, variations in viscosity, temperature, and even piping with non uniform (rough) internal. surface finishes. With. so many variables and coefficients, the D/W formula only became practical and popular after the invention of the electronic calculator. The D/W forntula is extensive and eomplicated, compared to the empirieal estimations of Mr. H W. 

Another concept that has become quite popular in industry is the balanced mechanical seal. Most manufacturers offer seal models incorporating the balance feature. This balance is not a dynamic balance, but instead a relationship between the forces tending to open the faces in a mechanical seal and the forces tending to close the seal faces (Figure 13-8). 

The low-temperature chemistry evolved from the macroscopic description of a variety of chemical conversions in the condensed phase to microscopic models, merging with the general trend of present-day rate theory to include quantum effects and to work out a consistent quantal description of chemical reactions. Even though for unbound reactant and product states, i.e., for a gas-phase situation, the use of scattering theory allows one to introduce a formally exact concept of the rate constant as expressed via the flux-flux or related correlation functions, the applicability of this formulation to bound potential energy surfaces still remains an open question. 

Johnson, J. and Picton, P. (1995) Designing Intelligent Machines, Vol. 2, Concepts in Artificial Intelligence, Butterworth-Heineman (in association with The Open University), Oxford, UK. 

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