A Method of Predicting the Gas Properties Surrounding Aerospace Vehicles in Hypersonic Flight

This paper describes two computer programs which have been combined to obtain inviscid perfect and real gas flow fields around axisymmetric blunt nosed vehicles at zero angle of attack, at supersonic or hypersonic flight velocities (Reference 1). A blunt body computer program which calculates the subsonic portion of the flow field, and a method of characteristics computer program which determines the supersonic portion of the flow field, were integrated into a combined efficient single automatic computer program. The blunt body program1 s output automatically supplies the method of characteristics program with the necessary input it requires. The two programs were made mutually compatible and were physically linked together. The linking of the two programs is described. A drag calculation subroutine is described which was developed to integrate the pressure distribution on the body, in order to determine the total drag and drag coefficient of the body. A geometry subroutine was also developed to extend and improve the body geometry capability so as to include arbitrary aerodynamic body shapes

A Feasibility Study in Measuring Soft Tissue Artifacts on the Upper Leg Using Inertial and Magnetic Sensors

Soft-tissue artifacts cause inaccurate estimates of body segment orientations. The inertial sensor (or optical marker) is orientating (or displacing) with respect to the bone it has to measure, due to muscle and skin movement [1]. In this pilot study 11 inertial and magnetic sensors (MTw, Xsens Technologies) were placed on the rectus femoris, vastus medialis and vastus lateralis (upper leg). One sensor was positioned on the tendon plate behind the quadriceps (iliotibial tract, as used in Xsens MVN [1]) and used as reference sensor. Walking, active and passive knee extensions and muscle contractions without flexion/extension were recorded using one subject. The orientation of each sensor with respect to the reference sensor was calculated. During walking, relative orientations of up to 28.6º were measured (22.4±3.6º). During muscle contractions without flexion/extension the largest relative orientations were measured on the rectus femoris (up to 11.1º) [2]. This pilot showed that the ambulatory measurement of deformation of the upper leg is feasible; however, improving the measurement technology is required. We therefore have designed a new inertial and magnetic sensor system containing smaller sensors, based on the design of an instrumented glove for the assessment of hand kinematics [3]. This new sensor system will then be used to investigate soft-tissue artifacts more accurately; in particular we will focus on in-use estimation and elimination of these artifacts

Introduced species in the Maltese Islands

The aim of this paper is to review the situation regarding the introduction of non-native species of flora and fauna into the Maltese Islands and their surrounding waters. The introduction of non-native species is not a new phenomenon -- indeed it is a natural process in ecosystems, particularly island ones. Most oceanic islands are initially colonised by species coming from ‘overseas’. Those invaders that manage to gain a foothold and survive to breed and spread, eventually become the native biota. Invariably this biota will evolve characteristics that adapt it to the particular environment it is now living in, which may be substantially different from that of its native environment. Some island populations will eventually become so different from their ‘exotic’ ancestors that they become new species in their own right -- species that occur only on the particular island on which they live, that is, endemic. Continental islands, such as the Maltese Islands, are somewhat different since they may become connected to the continental mainland during sea-level lows, allowing easy access of mainland biota. During sea-level highs, the islands become cut off from the mainland and the biota becomes stranded. For example, in the case of the Maltese Islands, they received their initial biota when they were connected to the Sicilian mainland towards the end of the Miocene, and then became separated at the beginning of the Pliocene, some five million years ago (THAKE, 1985; GIUSTI et al., 1995). For those species with limited powers of dispersal, the island populations continue to evolve independently of their mainland ancestors, and here too endemic forms may arise. Superimposed on this, there is an influx of those mainland species which manage to cross the water.peer-reviewe

Blood ethanol concentrations during and following constant‐rate intravenous infusion of alcohol

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/117025/1/cpt1976192213.pd

Phugoid motion for grazing-entry trajectories at near-circular speeds

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77023/1/AIAA-26742-801.pd

TagScan: Simultaneous target imaging and material identification with commodity RFID devices

National Research Foundation (NRF) Singapore under IDM Futures Funding Initiativ

Efficient coal concentration using a short-chain amine-type compound as collector reagent: Flotation and optimization studies

This work presents the flotation of a sub-bituminous coal using 1-butylamine as a short-chain amine collector. The flotation results have been obtained with 1-butylamine (coal yield: 100%) and compared with those achieved with a quaternary amine (coal yield: 95.4%), kerosene (coal yield: 100%) and diesel (coal yield: 95.7%). The best results have been obtained with 1-butylamine. Less depressant effect has been observed with 1-butylamine. The FTIR signals have been attenuated when the coal is conditioned with 1-butylamine. Zeta potential measurements have also been changed after conditioning. The contact angle of water and graphite has decreased from 82.3° to 32.2°. An optimization has been performed using a Box-Behnken experimental design. Flotation has significantly affected by time and collector dosage. The pH is not a significant factor. The optimal conditions for the best efficiency using 1-butylamine as a collector are 2.0 min of flotation and 10-3 mol/L of collector

Bark beetles and pinhole borers (Curculionidae, Scolytinae, Platypodinae) alien to Europe

Invasive bark beetles are posing a major threat to forest resources around the world. DAISIE’s web-based and printed databases of invasive species in Europe provide an incomplete and misleading picture of the alien scolytines and platypodines. We present a review of the alien bark beetle fauna of Europe based on primary literature through 2009. We find that there are 18 Scolytinae and one Platypodinae species apparently established in Europe, from 14 different genera. Seventeen species are naturalized. We argue that Trypodendron laeve, commonly considered alien in Europe, is a native species; conversely, we hypothesize that Xyleborus pfeilii, which has always been treated as indigenous, is an alien species from Asia. We also point out the possibility that the Asian larch bark beetle Ips subelongatus is established in European Russia. We show that there has been a marked acceleration in the rate of new introductions to Europe, as is also happening in North America: seven alien species were first recorded in the last decade

River bank burrowing by invasive crayfish: Spatial distribution, biophysical controls and biogeomorphic significance

Invasive species generate significant global environmental and economic costs and represent a particularly potent threat to freshwater systems. The biogeomorphic impacts of invasive aquatic and riparian species on river processes and landforms remain largely unquantified, but have the potential to generate significant sediment management issues within invaded catchments. Several species of invasive (non-native) crayfish are known to burrow into river banks and visual evidence of river bank damage is generating public concern and media attention. Despite this, there is a paucity of understanding of burrow distribution, biophysical controls and the potential significance of this problem beyond a small number of local studies at heavily impacted sites. This paper presents the first multi-catchment analysis of this phenomenon, combining existing data on biophysical river properties and invasive crayfish observations with purpose-designed field surveys across 103 river reaches to derive key trends. Crayfish burrows were observed on the majority of reaches, but burrowing tended to be patchy in spatial distribution, concentrated in a small proportion (< 10%) of the length of rivers surveyed. Burrow distribution was better explained by local bank biophysical properties than by reach-scale properties, and burrowed banks were more likely to be characterised by cohesive bank material, steeper bank profiles with large areas of bare bank face, often on outer bend locations. Burrow excavation alone has delivered a considerable amount of sediment to invaded river systems in the surveyed sites (3 t km− 1 impacted bank) and this represents a minimum contribution and certainly an underestimate of the absolute yield (submerged burrows were not recorded). Furthermore, burrowing was associated with bank profiles that were either actively eroding or exposed to fluvial action and/or mass failure processes, providing the first quantitative evidence that invasive crayfish may cause or accelerate river bank instability and erosion in invaded catchments beyond the scale of individual burro