Swedish Defence Research Agency

About: Swedish Defence Research Agency is a government organization based out in Stockholm, Sweden. It is known for research contribution in the topics: Radar & Laser. The organization has 1413 authors who have published 2731 publications receiving 56083 citations. The organization is also known as: Totalförsvarets forskningsinstitut.

Russian Science and Technology is Still Having Problems—Implications for Defense Research

Abstract: Science and technology can play a crucial role in the long-term for the modernization of Russia and the armed forces, and many government initiatives have been approved but their implementation can be questioned. Russia has a strong science base into which it invests substantial funds, but that only to a limited extent generates competitive innovative products and services. The government still hopes the defense sector can be the driving force for innovation that is questioned in this article. The civilian research and development could be the driving force needed for promoting innovations but the problems that remain for the civilian science and technology sector are significant. The reform of the defense industry has been a long-time priority but very slow progress is being made due to difficulties to control it and because the problems facing the defense industries and research and development are even more serious in this sector in spite of large funding increases.

A five-field finite element formulation for nearly inextensible and nearly incompressible finite hyperelasticity

Abstract: A novel Hu-Washizu type 5-field virtual work principle for nearly inextensible and almost incompressible finite hyperelasticity is developed and implemented The formulation is implemented in an hp-adaptive code providing the proper flexible environment for finite elements with variable order and mixed interpolation The novel implementation includes residual based error estimation and mesh adaptivity In the fully constrained limit the formulation provides the constraint manifold setting of hyperelasticity with the simple internal kinematic constraints of inextensibility and incompressibility A study using a semi-inverse analytical solution and h-refinements and p-enrichments corroborates the convergence characteristics of the 5-field implementation A new closed form solution for pure torsion of a circular cylindrical tube with inextensible fibres is derived and used for verification As typical applications are found in eg soft tissue biomechanics, passive pressurisation of an ellipsoidal geometry resembling the left ventricle of a rabbit heart is analysed to demonstrate the capability of modelling transversely isotropic materials

Genome sequence of Coxiella burnetii strain Namibia

Abstract: We present the whole genome sequence and annotation of the Coxiella burnetii strain Namibia. This strain was isolated from an aborting goat in 1991 in Windhoek, Namibia. The plasmid type QpRS was confirmed in our work. Further genomic typing placed the strain into a unique genomic group. The genome sequence is 2,101,438 bp long and contains 1,979 protein-coding and 51 RNA genes, including one rRNA operon. To overcome the poor yield from cell culture systems, an additional DNA enrichment with whole genome amplification (WGA) methods was applied. We describe a bioinformatics pipeline for improved genome assembly including several filters with a special focus on WGA characteristics.

Distributed scheduling for mobile ad hoc networks - a novel approach

Abstract: Spatial reuse TDMA (STDMA) is a collision-free access scheme for ad hoc networks. The idea is to let spatially separated radio terminals reuse the same time slot when the resulting interferences are not too severe. In this paper we first describe the properties a distributed STDMA algorithm must have in order to be efficient. No existing algorithm fulfills all of these properties. Second we focus on how to efficiently use distributed information and describe an algorithm that can handle different amount of information. Furthermore, we evaluate this algorithm for different information and show that it can give the same capacity as a centralized reference algorithm.

Analysis of capacity in ad hoc networks with variable data rates

Abstract: We investigate how to use a variable data rate in ad hoc TDMA networks and the possible gain in throughput. The use of variable data rates enables the network to adapt to changes in the environment, which is crucial for the ability to guarantee QoS in a mobile network. We study the impact of the routing metric and traffic adaptivity on the network's ability to utilize variable data rates. The results show that it is of paramount importance to take data rate into consideration when routing, especially when a variable data rate is used to add long-range, low data rate links. Further, traffic adaptivity plays an important role in the utilization of variable data rates at the network level. We also study how the number of data rates to choose from affects the throughput. For the studied network topologies, the benefit of having many data rates is not obvious. Furthermore, the results show a substantial improvement in throughput for a system with a variable data rate compared to a system with a fixed data rate.