Papers by Keyword: CAD Models

Abstract: This paper presents the concept of the system adding designer work using fuzzy analysis of the notes of design requirements and solutions. Design requirements are generated basing on the proposed model of the technical mean life cycle. It includes three phases of life of a technical mean: its formation, its existence and its liquidation. In this perspective there are examined five general requirements associated with: the technical need, a man, the technical culture, the society and the environment. The design solutions are created basing on the concept of an universal structure of technical means. The structure of the system has following components: structural system, drive system and control system. Structural system is determined as the integrator of the whole structure of a complex technical mean. The drive system is secondary to the structural system. The third in the order of the systems is the control system. It is developed last so it must take into account the solutions developed for the structural system and the drive system. Generating constructional solutions is carried out in the three distinguished features of a construction: geometric, material and dynamic. The presented methodology is illustrated by the example of designing specific technical mean.

Abstract: The assembly building is sought after by people For its speed, subject to the constraints of climate conditions, seismic energy saving and environmental protection, construction of low cost, flexible and diverse housing. However, in the assembly building maintenance, scrap processing and recycling of how to improve the efficiency of demolition is a new issue to be resolved. In this paper, based on the components of the demolition wave optional disassembly planning algorithm, by the definition of prefabricated building demolition wave is a topological relationship of certain components in the assembly building to reflect the components of the demolition order. The calculation of the algorithm is small, easy to use it to carry out efficient search, optional optimal component disassembly sequence, and thus improve the efficiency of disassembly.

Abstract: Currently there has been much interested in developing the watermarking for 3D graphic data of NURBS or mesh model, for its function of copyright protecting, private detection under the network environment. Since the majority of computer aided design (CAD) applications employ parametric curves and surfaces, this paper proposes a watermarking mechanism for CAD models, those employ non-uniform rational B-spine (NURBS) curves and surfaces as their main shape-defining primitives. This algorithm using relative knot insertion method embeds the watermarks generated by features sequence identification into the NURBS primitives. The shapes are exactly preserved. We don’t need ether original model or original message to extract the watermarks from the watermarked models, since it is blind. By experimental result, we confirmed the watermarking mechanism is robust against most common attacks.