SUMMARYThis article presents two new methods for adaptive reÿnement of a B-spline ÿnite element solution within an integrated mechanically based computer aided engineering system.The proposed techniques for adaptively reÿning a B-spline ÿnite element solution are a local variant of np-reÿnement and a local variant of h-reÿnement. The key component in the np-reÿnement is the linear co-ordinate transformation introduced into the reÿned element. The transformation is constructed in such a way that the transformed nodal conÿguration of the reÿned element is identical to the nodal conÿguration of the neighbour elements. Therefore, the assembly proceeds as with classic ÿnite elements, while the solution approximation conforms exactly along the inter-element boundaries. For the h-reÿnement, this transformation is introduced into a construction that merges the super element from the ÿnite element world with the hierarchical B-spline representation from the computational geometry. In the scope of developing sculptured surfaces, the proposed approach supports C 0 as well as the Hermite B-spline C 1 continuous shapes. For sculptured solids, C 0 continuity only is considered in this article.The feasibility of the proposed methods in the scope of the geometric design is demonstrated by several examples of creating sculptured surfaces and volumetric solids. Numerical performance of the methods is demonstrated for a test case of the two-dimensional Poisson equation.

In most existing CAD systems, geometrical design and mechanical analysis are operated as completely separate modules. Intensive interaction between these modules is, however, highly desired due to the iterative nature of a typical product development process. Formulating a new, unified approach to design and analysis that provides a high level of interaction is the main purpose of this research. The idea is to integrate a mechanically based geometrical design concept with the mechanical analysis module in a uniform B-Spline Finite Element (BSFE) environment. In this paper, the BSFE method is formulated and its validity and adequacy are verified for elastic linear rod and plate models. In particular, the feasibility of applying B-spline functions as base functions of the finite element method for design and analysis is demonstrated. Unique scheme attributes based on intrinsic properties of B-spline functions are investigated in detail. Method adequacy is demonstrated by comparing convergence characteristics, complexity and computational cost to the spectral element method.

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Today in Russia the urgent question of preparation of qualified specialists for the construction industry. Appearance of new types of work requires workers, foremen and superintendents know how most effectively to manage the construction process, and often it is impossible without a qualitatively prepared the technological card on a certain type of work. Routing is an integral part of the design and technological documentation. It is necessary to modernize the process of formation of technological cards and create a new one, following the trends of development of the construction industry. Use of modern information technologies for the formation of technological cards will eliminate a number of personnel issues facing the construction complex. Raise the level of preparation of design and technological documentation will be possible due to introduction of methods, models, algorithms for automation of documentation. The process of development of technological cards in construction is one of the most difficult and complex and, at the same time, the least automated. Therefore, development of new models and methods of automation, change the very process of creating this section of organizational and technological documentation, will allow to solve an actual problem of improvement of quality of formation of technological cards, reduce time and cost of construction. Methodological and theoretical basis of research includes: the theory and practice of CAD, system analysis and construction or for system architect, database design, theory of algorithms, thematic work of the authors, the normative documentation in the field.

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