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In this paper, a new hybrid parallelisable low order algorithm, developed by the authors for multibody dynamics analysis, is implemented numerically on a distributed memory parallel computing system. The presented implementation can currently accommodate the general spatial motion of chain systems, but key issues for its extension to general tree and closed loop systems are discussed. Explicit algebraic constraints are used to increase coarse grain parallelism, and to study the influence of the dimension of system constraint load equations on the computational efficiency of the algorithm for real parallel implementation using the Message Passing Interface (MPI). The equation formulation parallelism and linear system solution strategies which are used to reduce communication overhead are addressed. Numerical results indicate that the algorithm is scalable, that significant speed-up can be obtained, and that a quasi-logarithmic relation exists between time needed for a function call and numbers of processors used. This result agrees well with theoretical performance predictions. Numerical comparisons with results obtained from independently developed analysis codes have validated the correctness of the new hybrid parallelisable low order algorithm, and demonstrated certain computational advantages.

In this rat model of acute tendon-bone injury repair, daily subcutaneous postoperative human growth hormone treatment for fourteen days failed to demonstrate a significant difference in any biomechanical parameter compared with placebo. Furthermore, subcutaneous administration of 5 mg/kg of human growth hormone twice daily from seven days preoperatively until twenty-eight days postoperatively demonstrated lower loads to ultimate failure and a higher risk of bone fracture failure compared with placebo.

For certain topics in the curriculum the pendulum of engineering education is swinging from a full focus on pure theory to a balance between theoretical analysis and solid experiences. Undergraduate students are required to obtain both theoretical knowledge and hands-on experiences to meet the need of job markets. Active learning/teaching has become a commonly-used instructional approach in response to this change of the balance. In the authors’ institute, the Design of Machine Elements (DOME) course has been used as a candidate for exploration on how to engage students in active learning in regular classroom settings through designed activities such as in-class-teams, think-pair-share, in-class-writing-assignments, problem-based learning, etc. If students are expected to perform well with open-ended and project-centered problems for their design courses and capstone senior design, then a pedagogical basis should be provided across the entire undergraduate design curriculum. This paper discusses how active learning/teaching techniques have been explored in teaching the course of Design of Machine Elements to build up such a basis. In this paper, active learning concepts applied in teaching the DOME course are discussed, including specific examples of integrating active learning techniques with traditional classroom lectures. Also presented are which active learning techniques have worked effectively, what experiences have been learned, and what issues need further improvements and exploration. In addition, the paper also discusses how course projects are assigned to line up with planned teaching and learning activities, and how project requirements have been designed to facilitate the integration of active learning techniques with instructional objectives. Anonymous student survey data and course assessments will be presented to show that these techniques indeed provide a promising solution to the integration of active learning/teaching methods into teaching the course of design of machine elements in the regular classroom setting.