Integration of Non-Destructive Evaluation-based Ultrasonic Simulation: A means for simulation in structural health monitoring

Simulation has become a prerequisite in engineering and science today for visualization of ideas and concepts. In non-destructive evaluation, simulation is increasingly used to show how an inspection method functions with regard to the component to be inspected and is even used for determining the probability of detection of a respective flaw with regard to the inspection method applied. Probability of detection in non-destructive evaluation is optimized in a way that the best sensor positions, as well as sensor tracking paths, can be found through simulation. In classical non-destructive evaluation, a transducer or transducer array can be virtually moved over the surface of a component to be inspected until a full capture of the component's surface and hopefully volume is achieved in terms of the inspection process. However, with structural health monitoring, no movement of the transducers is possible in case those become an integral and hence fixed part of the component considered. Determining the optimum position of a respective structural health monitoring transducer network can therefore only be achieved through optimization procedures, where numerical simulation is possibly the only viable solution to get this done. Establishing a numerical simulation platform for structural health monitoring purposes has been the major objective of the recently completed INDEUS (Integration of Non-Destructive Evaluation-based Ultrasonic Simulation) project, which is described in this article. The open simulation platform includes different simulation tools, where the requirements and options for further extension of those tools and different test cases applied for validation so far are described. The target is to even simulate real complex structures such as applied in civil, aeronautical, and other engineering disciplines made of metallic and polymer-based monolithic and composite materials where the digital models are inherited from traditional computer-aided design and finite element-based designs. This lays the ground for determining the probability of damage for a given loading condition and structure, and the propagation of guided waves in the structure considered for an undamaged and a damage tolerant condition. From those simulation results, the determination of an optimum configuration of sensing transducers for a given set of actuating transducers is then shown for a guided wave-based structural health monitoring system solution to be designed allowing the tolerable damage to be detected reliably

Demographic and clinical profiles of Plasmodium falciparum and Plasmodium vivax patients at a tertiary care centre in southwestern India

Background: Malaria remains an important cause of morbidity and mortality in India. Though many comprehensive studies have been carried out in Africa and Southeast Asia to characterize and examine determinants of Plasmodium falciparum and Plasmodium vivax malaria pathogenesis, fewer have been conducted in India. Methods: A prospective study of malaria-positive individuals was conducted at Goa Medical College and Hospital (GMC) from 2012 to 2015 to identify demographic, diagnostic and clinical indicators associated with P. falciparum and P. vivax infection on univariate analysis. Results: Between 2012 and 2015, 74,571 febrile individuals, 6287 (8.4%) of whom were malaria positive, presented to GMC. The total number of malaria cases at GMC increased more than two-fold over four years, with both P. vivax and P. falciparum cases present year-round. Some 1116 malaria-positive individuals (mean age = 27, 91% male), 88.2% of whom were born outside of Goa and 51% of whom were construction workers, were enroled in the study. Of 1088 confirmed malaria-positive patients, 77.0% had P. vivax, 21.0% had P. falciparum and 2.0% had mixed malaria. Patients over 40 years of age and with P. falciparum infection were significantly (p < 0.001) more likely to be hospitalised than younger and P. vivax patients, respectively. While approximately equal percentages of hospitalised P. falciparum (76.6%) and P. vivax (78.9%) cases presented with at least one WHO severity indicator, a greater percentage of P. falciparum inpatients presented with at least two (43.9%, p < 0.05) and at least three (29.9%, p < 0.01) severity features. There were six deaths among the 182 hospitalised malaria positive patients, all of whom had P. falciparum. Conclusion: During the four year study period at GMC, the number of malaria cases increased substantially and the greatest burden of severe disease was contributed by P. falciparum