The objective of this article is to introduce a new method including model order reduction for the life prediction of structures subjected to cycling damage. Contrary to classical incremental schemes for damage computation, a non-incremental technique, the LATIN method, is used herein as a solution framework. This approach allows to introduce a PGD model reduction technique which leads to a drastic reduction of the computational cost. The proposed framework is exemplified for structures subjected to cyclic loading, where damage is considered to be isotropic and micro-defect closure effects are taken into account. A difficulty herein for the use of the LATIN method comes from the state laws which can not be transformed into linear relations through an internal variable transformation. A specific treatment of this issue is introduced in this work.

One of the challenges of fatigue simulation using continuum damage mechanics framework over the years has been reduction of numerical cost while maintaining acceptable accuracy. The extremely high numerical expense is due to the temporal part of the quantities of interest which must reflect the state of a structure that is subjected to exorbitant number of load cycles. A novel attempt here is to present a non-incremental LATIN-PGD framework incorporating temporal model order reduction. LATIN-PGD method is based on separation of spatial and temporal parts of the mechanical variables, thereby allowing for separate treatment of the temporal problem. The internal variables, especially damage, although extraneous to the variable separation, must also be treated in a tactical way to reduce numerical expense. A temporal multi-scale approach is proposed that is based on the idea that the quantities of interest show a slow evolution along the cycles and a rapid evolution within the cycles. This assumption boils down to a finite element like discretisation of the temporal domain using a set of "nodal cycles" defined on the slow time scale. Within them, the quantities of interest must satisfy the global admissibility conditions and constitutive relations with respect to the fast time scale. Thereafter, information of the "nodal cycles" can be interpolated to simulate the behaviour on the whole temporal domain. This numerical strategy is tested on different academic examples and leads to an extreme reduction in numerical expense.

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P urpose: To study the aetiology, epidemiological profile of patients presenting with ocular trauma and compare visual outcomes of early versus late presentatiod. Design: Prospective observational study performed over fifteen month interval. Methods: Patients' epidemiological characteristics were evaluated along with cause of trauma, place of injury, time lag post injury, and postoperative management. Injuries were classified by Birmingham Eye Trauma Terminology (BETT). Final visual and anatomical outcome after providing tailored surgical management was evaluated. All patients had a minimum follow up of 6 months. Statistical Analysis: All the data collected was analysed using SPSS version 17.0 software. Results: One hundred and three cases of incident ocular injury were included in the study. Open globe: closed globe injuries were 78:22% respectively with intraocular foreign body present in 9% of cases. Actively working adults younger than 25 years of age were the commonest age group affected (64%). The commonest place of injury was at home (32%) followed by workplace environment (29%). Good outcome (vision of > 6/60 Snellen) could be achieved in 50% cases, of which 53% had purely anterior segment injury and 20% concomitant retinal injury. Good outcome had a direct correlation with early presentation in 57% and poor outcome with late presentation seen in 64% cases. Conclusion: Serious ocular trauma frequently occurs at home with the younger population maximum at risk. Good visual acuity is associated with early intervention and purely anterior segment injuries.

A systematic investigation on electrical fatigue in lead zirconate titanate (PZT) is carried out for different loading frequencies. Experiments are conducted up to 106 cycles to measure the electrical displacement and longitudinal strain on bulk ceramics in the bipolar mode with large electrical loading conditions. A simplified macroscopic model based on physical mechanisms of domain switching is developed to predict the non-linear behaviour. In this model, the volume fraction of a domain is used as the internal variable by considering the mechanisms of domain nucleation and propagation (domain wall movement). The measured material properties at different fatigue cycles are incorporated into the switching model as damage parameters and the classical strain versus electric field and electric displacement versus electric field curves are simulated. Comparison between the experiments and simulations shows that the proposed model can reproduce the characteristics of non-linear as well as fatigue responses.

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Osteosynthesis with open reduction technique in comminuted fracture has several disadvantages like increase rate of non-union, soft tissue problem, infection and implant failure. These problems may be overcome by percutaneous bridge plating technique which preserve the vascularity and soft tissue attachment of fracture fragments. MATERIALS AND METHODS: Twenty-five patients were involve in this study. All of twentyfive patients with closed comminuted diaphyseal fractures of femur (n-10) and tibia (n-15) were operated on using the principle indirect reduction and biological fixation with bridge plate under image intensifier. Partial and full weight bearing were allowed according to clinical and radiological union. RESULTS: Most regained excellent range of motion of knee and ankle. Mean time of radiological union was 20.12 weeks. Two patients had superficial skin problem which healed with local wound care. One patient had non union which was healed by bone grafting. In this study excellent result was seen in 18 cases, good in five and fair in two patients. CONCLUSION: Our study indicates that minimally invasive bridge plating is an effective alternative for treatment of comminuted diaphyseal fracture of long bones. These complex fractures give complete recovery of normal limb function at an early stage with less complication.