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In conceptual design, behavior information often plays a pivotal role in mapping from function to structure. Behavioral process is a detailed description of a number of linked sub-level behaviors, which characterize the process of an overall behavior. To understand this process, as well as to provide assistance to designers for design synthesis, it is necessary to construct an appropriate behavioral process model, for which two aspects of design information need to be identified first. One is the characteristics of behavior itself, and the other is the relations between individual behaviors. In this paper, the characteristics of behavior are clarified and the relations of behaviors such as loop relation, temporal relation and state relation together with causal relation are identified. Based on the existing Causal Behavioral Process (CBP) model, an extended CBP (E-CBP) model is proposed by adding these new behavioral characteristics and relations. An Extended Backus-Naur Form (EBNF) representation method is also proposed to represent the E-CBP model. An electric nailing device design case and a lever-clamp assembly system design cases are illustrated to demonstrate the usefulness and applicability of the E-CBP model as well as its representation method.

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The surfaces and hyperpatch models constructed by the NURBS-based approach provide an advantage of shape modification and have varying mesh-structure. No observations based on material distribution on the surface and hyperpatch models were done until now. The heterogeneous models of the NURBS surface and NURBS solid hyperpatch models were based on the Unevaluated models as per the Control-Point-Based modelling approach was followed. The material allocated gets interpolated over the surface and hyperpatch models. The material distribution does vary, and the effect of weight variation on material allocation does become significant for them.

Bone is a highly heterogeneous object. Its composition and structure both vary and depends upon skeletal site, physiological function and age. The goal of this study is to investigate the importance of including material anisotropy in B-Spline based heterogeneous graded (BSBHG) FE model of proximal femur. Five different BSBHG FE models are developed. Out of these five models, four are orthotropic models and one is isotropic model. Each model is simulated in simple stance load condition and their biomechanical response is evaluated and compared with each other as well as those of experimental results given in one of the reference paper for the same specimen in simple stance load condition. The Lagrangian graded element approach is used to assign inhomogeneous isotropic and orthotropic elastic constants in finite element model to improve the performance. Based on the analysis of the two parameters, maximum equivalent Von Mises stress and the displacement in 'z' direction, comparison is achieved. The displacement and Von Mises results have shown that there is small difference between one of the orthotropic model and the isotropic model while the displacement results of the other two orthotropic models show good agreement with the experimental findings. The global strain prediction accuracy for orthotropic model has improved over isotropic model: the regression coefficient increased from 0.63 to 0.9-0.96.