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 & Synthetic aperture radar. The organization has 1413 authors who have published 2731 publications receiving 56083 citations. The organization is also known as: Totalförsvarets forskningsinstitut.

Experimental Studies of Anode and Cathode Materials in a Repetitive Driven Axial Vircator

Abstract: Repetitive use of a high-power-microwave radiation source implies strong erosion on cathode and anode materials. Electrode-material endurance has been studied in a series of experiments with an axial virtual cathode oscillator powered by a compact Marx generator. The Marx generator is operated in a 10-Hz repetitive mode with a burst of ten pulses. Velvet and graphite was used as electron-emitting materials, and they showed markedly different pulse characteristics. The following three different anode materials were used: stainless-steel mesh, stainless-steel wires, and molybdenum wires, which all had different influence on the pulse characteristics.

Vibrotactile and visual threat cueing with high G threat intercept in dynamic flight simulation

Abstract: In a TNO and FOI joint study, nine fighter pilots participated in a threat detection and intercept experiment in the Swedish Dynamic Flight Simulator. Visual threat cueing with a simulated Gripen aircraft head-up display (HUD) symbology was compared with combined visual and vibrotactile threat cueing by means of the HUD symbology and a TNO Tactile Torso Display consisting of 60 vibrators in a matrix covering the pilot’s torso. Each fighter pilot detected and intercepted 32 threats while pulling G-loads up to +8-9Gz. The high G-loads neither critically affected the tactile vest equipment nor the human sensory system, and visual/tactile cueing generated an overall faster RT to threat pop-ups compared with visual cueing alone. The pilots’ highest ratings of the tactile cueing were for capturing attention and indicating initial threat direction at threat pop-up. Thus, tactile threat cueing could enhance visual cueing and threat awareness in fighter aircraft.

Emission Factors for Gases and Particle-Bound Substances Produced by Firing Lead-Free Small-Caliber Ammunition

Abstract: Lead-free ammunition is becoming increasingly popular because of the environmental and human health issues associated with the use of leaded ammunition. However, there is a lack of data on the emissions produced by firing such ammunition. We report emission factors for toxic gases and particle-bound compounds produced by firing lead-free ammunition in a test chamber. Carbon monoxide, ammonia, and hydrogen cyanide levels within the chamber were analysed by Fourier transform infrared spectroscopy, while total suspended particles and respirable particles were determined gravimetrically. The metal content of the particulate emissions was determined and the associated organic compounds were characterized in detail using a method based on thermal desorption coupled to gas chromatography and mass spectrometry. The particulate matter (∼30 mg/round) consisted primarily of metals such as Cu, Zn, and Fe along with soot arising from incomplete combustion. Nitrogen-containing heterocyclic aromatic compounds such as ca...

Light-ion production in the interaction of 96 MeV neutrons with carbon

Abstract: Double-differential cross sections are reported for light-ion (p, d, t, $^{3}\mathrm{He}$, and \ensuremath{\alpha}) production in oxygen induced by 96 MeV neutrons. Energy spectra are measured at eight laboratory angles from 20\ifmmode^\circ\else\textdegree\fi{} to 160\ifmmode^\circ\else\textdegree\fi{} in steps of 20\ifmmode^\circ\else\textdegree\fi{}. Procedures for data taking and data reduction are presented. Deduced energy-differential and production cross sections are reported. Experimental cross sections are compared to theoretical reaction model calculations and experimental data at lower neutron energies in the literature. The measured proton data agree reasonably well with the results of the model calculations, whereas the agreement for the other particles is less convincing. The measured production cross sections for protons, deuterons, tritons, and \ensuremath{\alpha} particles support the trends suggested by data at lower energies.