An adjacency representation for structural topology optimization using genetic algorithm

A new approach for continuum structural topology optimization using genetic algorithms is presented in this paper. The proposed approach is based on a representation by adjacency where the principle is founded on the concept of connectivity of finite elements, considered as cells. This principle is expressed by an adjacency matrix similar to that used in the graph theory. The encoding of the structure solutions uses this matrix by transforming it into a binary string. The research of optimal solution, i.e. the optimal material distribution, is interpreted in this approach by the determination of the connectivity of elements (cells). Using density variable, the approach has some common points with the homogenization techniques. The proposed approach is tested with simple benchmark applications

Evaluation of the current treatment concepts in Germany, Austria and Switzerland for acute traumatic lesions to the prepatellar and olecranon bursa

Background: Although traumatic lacerations of the olecranon (OB) and praepatellar bursae (PB) are common entities often associated with complications, no study could be found on this injury. The aim of this study was to survey the current treatment concepts for acute traumatic laceration of the OB and PB in Germany, Austria and Switzerland. Materials and methods: An international online survey was conducted among orthopaedic and trauma surgeons in Germany (TraumaNetwork DGU), Austria (Austrian Society of Trauma (OGU) and Orthopaedic (OGO) Surgeons) and Switzerland (Swiss Orthopaedic Surgeons and Swiss Society of Infectious Disease (CH)) (n = 1967). The survey comprised of five demographical questions, the current treatment concepts were evaluated using a case study. Results: The overall-response-rate was 16% (12-46%). 88% of the responding physicians were male, aged 47.5 +/- 10.2 years with a mean working experience of 20.1 +/- 10.6 years. 54% of the surveyed physicians were either senior or chief physicians. Treatment concepts varied significantly between DGU and OGO/CH (p = 0.02/p = 0.006), no significant differences could be found between DGU and OGU. Generally, German and Austrian trauma surgeons favoured bursectomy (86.7%/90.9%) and immobilisation (68.3%/77.3%). Austrian orthopaedic surgeons performed fewer bursectomies (69.3%) but had the highest proportion for administering antibiotics (73.9%). Less than 50% of Swiss physicians indicated bursectomy as a treatment option. Conclusion: Overall, this survey revealed a significant heterogeneity in treatment approaches in Central Europe. Further evidence is needed to identify the best treatment concepts for traumatic lacerations of the OB and PB. (c) 2012 Elsevier Ltd. All rights reserved