Combining multiple knowledge bases

Combining knowledge present in multiple knowledge base systems into a single knowledge base is discussed. A knowledge based system can be considered an extension of a deductive database in that it permits function symbols as part of the theory. Alternative knowledge bases that deal with the same subject matter are considered. The authors define the concept of combining knowledge present in a set of knowledge bases and present algorithms to maximally combine them so that the combination is consistent with respect to the integrity constraints associated with the knowledge bases. For this, the authors define the concept of maximality and prove that the algorithms presented combine the knowledge bases to generate a maximal theory. The authors also discuss the relationships between combining multiple knowledge bases and the view update problem     

Finite-element grid improvement by minimization of stiffness matrix trace

A new and simple method of finite-element grid improvement is presented. The objective is to improve the accuracy of the analysis. The procedure is based on a minimization of the trace of the stiffness matrix. For a broad class of problems this minimization is seen to be equivalent to minimizing the potential energy. The method is illustrated with the classical tapered bar problem examined earlier by Prager and Masur. Identical results are obtained.     

Resonant neutron filters in elemental analysis and radiography

Translated from Atomnaya Énergiya, Vol. 67, No. 4, pp. 271–274, October, 1989.     

A mixed finite element model for the elastic contact problem

The static elastic contact problem is approached using Lagrange multipliers, leading to a mixed finite element problem. A non-linear friction law is introduced explicitly and the non-local character of the friction phenomena is implicitly assumed. In order to avoid stress oscillations near singular points, a perturbed Lagrangian functional is considered. The algorithms herein proposed do not impose nodal dependencies over the contact surfaces, allowing for the independent discretization of both bodies. The method is able to model simultaneous contact over different regions of any geometrical shape. Computer code, examples and results presented here are restricted to axisymmetrical and bidimensional cases.     

Multifunctional alkylphenol additive

Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 2, pp. 14–15, February, 1989.     

A psychological study of advanced manufacturing technology: the concept of coupling

The role played by technology as a discrete independent variable in shaping the design of work is explored. The concept of coupling is developed and an empirical study of work with advanced manufacturing technology (AMT), using measurement scales derived from this concept, is outlined. Results indicate that operators of tightly coupled AMT perceive stronger supervisory influence on their working methods and show signs of lower intrinsic job satisfaction and poorer mental health than operators of more loosely coupled AMT. Implications for job redesign are discussed.     

Some Aspects of Binding GKS to C++

Aspects of a prototype binding of GKS to the C++ programming language are presented. The binding makes use of classes and derived classes to define GKS concepts such as segments and workstations. Operator overloading is used for some GKS Functions.     

Magnetic anisotropy of Co-Cr thin films as a function of substrate temperature during deposition

A sequence of Co78Cr22films, 500 nm in thickness, was prepared by deposition on glass in a modified Varian D.C. magnetron S-gun sputtering system. The substrate temperature during deposition, Ts, was fixed at various values with an upper limit of 300°C. Specimens were examined by VSM, TM, FMR and TEM. Msrises significantly with increasing Ts, peaking at 200°C at 370 emu/cm³. The effective volume-averaged anisotropy drops for Ts>110°C from +1.6 KOe to progressively negative values (-4.3 KOe at 300°C). From FMR we find indications of the presence, in addition to the transition and bulk layers, of a highly negative anisotropy constituent (sim-11.5KOe anisotropy field). This resonance appears at Tsvalues of 150°C and above. TEM plane and cross-section views taken on a Ts= 150°C specimen show islands composed of tilted columns within the bulk. For vertical recording, specimens prepared at Tsvalues between 50 and 100°C are recommended. On the other hand, for longitudinal recording applications, films prepared at Tsvalues above 250°C would seem to be appropriate.     

Relation of registration with yield and termination of first lactation in dairy goats

First lactation records of 9941 Alpine, 2383 LaMancha, 11,203 Nubian, 3714 Saanen, and 4649 Toggenburg dairy goat does were obtained from the USDA to evaluate relation of registration (purebred, American, or grade) with lactation yield traits (mature equivalent milk and fat yields) and with reason for termination of lactation (normal, sold for dairy, or culled). Does were grouped by age at first kidding (11 through 16 mo or 21 through 26 mo) and by calendar year (1976 through 1978, 1979 through 1981, or 1982 through 1984). Data were analyzed within breed and year group for yield traits and within breed for reason of termination. Registration and age at first kidding accounted for little variation in mature equivalent milk and fat yields or in reason for termination.