Saab Automobile AB

About: Saab Automobile AB is a based out in . It is known for research contribution in the topics: Radar & Antenna (radio). The organization has 760 authors who have published 890 publications receiving 11811 citations.

Application of a line-implicit scheme on stretched unstructured grids

Abstract: A line-implicit Runge-Kutta time stepping scheme is derived, implemented and applied. It is applied to fluid flow problems governed by the Navier-Stokes equations on stretched unstructured grids. The flow equations are integrated implicitly in time along structured lines in regions where the grid is stretched, typically in the boundary layer, and explicitly elsewhere. The integration technique is introduced for steady state problems with the intention to speed up the rate of convergence. It is extended to unsteady problems by a dual time stepping approach. The paper focuses on the implementation of the line-implicit scheme starting from an explicit multigrid flow solver and on the application of it. Numerical results are presented for test cases in two and three dimensions for inviscid and viscous flow problems. The line-implicit time integration convergence rates are compared to pure explicit convergence rates and the gain is quantified in terms of reduction of iterations and CPU time. All presented test cases show improved convergence rates. The gain is highest for the three dimensional test cases for which reductions of up to 75% of the computing time is obtained.

Safe management of bodies of deceased persons with suspected or confirmed COVID-19: a rapid systematic review.

Abstract: Introduction Proper strategies to minimise the risk of infection in individuals handling the bodies of deceased persons infected with 2019 novel coronavirus (2019-nCoV) are urgently needed. The objective of this study was to systematically review the literature to scope and assess the effects of specific strategies for the management of the bodies. Methods We searched five general, three Chinese and four coronavirus disease (COVID-19)–specific electronic databases. We searched registries of clinical trials, websites of governmental and other relevant organisations, reference lists of the included papers and relevant systematic reviews, and Epistemonikos for relevant systematic reviews. We included guidance documents providing practical advice on the handling of bodies of deceased persons with suspected or confirmed COVID-19. Then, we sought primary evidence of any study design reporting on the efficacy and safety of the identified strategies in coronaviruses. We included evidence relevant to contextual factors (ie, acceptability). A single reviewer extracted data using a pilot-tested form and graded the certainty of the evidence using the GRADE approach. A second reviewer verified the data and assessments. Results We identified one study proposing an uncommon strategy for autopsies for patients with severe acute respiratory syndrome. The study provided very low-certainty evidence that it reduced the risk of transmission. We identified 23 guidance documents providing practical advice on the steps of handling the bodies: preparation, packing, and others and advice related to both the handling of the dead bodies and the use of personal protective equipment by individuals handling them. We did not identify COVID-19 evidence relevant to any of these steps. Conclusion While a substantive number of guidance documents propose specific strategies, we identified no study providing direct evidence for the effects of any of those strategies. While this review highlights major research gaps, it allows interested entities to build their own guidance.

Side lobe suppression

Abstract: Embodiments include a method to suppress side lobes of a main antenna by creating cancellation directions using a Side Lobe Canceller (SLC) Various embodiments also provide the Side Lobe Canceller

Measuring and Visualizing Code Stability -- A Case Study at Three Companies

Abstract: Monitoring performance of software development organizations can be achieved from a number of perspectives - e.g. using such tools as Balanced Scorecards or corporate dashboards. In this paper we present results from a study on using code stability indicators as a tool for product stability and organizational performance, conducted at three different software development companies - Ericsson AB, Saab AB Electronic Defense Systems (Saab) and Volvo Group Trucks Technology (Volvo Group). The results show that visualizing the source code changes using heat maps and linking these visualizations to defect inflow profiles provide indicators of how stable the product under development is and whether quality assurance efforts should be directed to specific parts of the product. Observing the indicator and making decisions based on its visualization leads to shorter feedback loops between development and test, thus resulting in lower development costs, shorter lead time and increased quality. The industrial case study in the paper shows that the indicator and its visualization can show whether the modifications of software products are focused on parts of the code base or are spread widely throughout the product.