Technology research for strapdown inertial experiment and digital flight control and guidance

A helicopter flight-test program to evaluate the performance of Honeywell's Tetrad - a strapdown, laser gyro, inertial navitation system is discussed. The results of 34 flights showed a mean final navigational velocity error of 5.06 knots, with a standard deviation of 3.84 knots; a corresponding mean final position error of 2.66 n.mi., with a standard deviation of 1.48 n.m.; and a modeled mean-position-error growth rate for the 34 tests of 1.96 knots, with a standard deviation of 1.09 knots. Tetrad's four-ring laser gyros provided reliable and accurate angular rate sensing during the test program and on sensor failures were detected during the evaluation. Criteria suitable for investigating cockpit systems in rotorcraft were developed. This criteria led to the development of two basic simulators. The first was a standard simulator which could be used to obtain baseline information for studying pilot workload and interactions. The second was an advanced simulator which integrated the RODAAS developed by Honeywell into this simulator. The second area also included surveying the aerospace industry to determine the level of use and impact of microcomputers and related components on avionics systems

Ab initio parametrised model of strain-dependent solubility of H in alpha-iron

The calculated effects of interstitial hydrogen on the elastic properties of alpha-iron from our earlier work are used to describe the H interactions with homogeneous strain fields using ab initio methods. In particular we calculate the H solublility in Fe subject to hydrostatic, uniaxial, and shear strain. For comparison, these interactions are parametrised successfully using a simple model with parameters entirely derived from ab initio methods. The results are used to predict the solubility of H in spatially-varying elastic strain fields, representative of realistic dislocations outside their core. We find a strong directional dependence of the H-dislocation interaction, leading to strong attraction of H by the axial strain components of edge dislocations and by screw dislocations oriented along the critical slip direction. We further find a H concentration enhancement around dislocation cores, consistent with experimental observations.Comment: part 2/2 from splitting of 1009.3784 (first part was 1102.0187), minor changes from previous version

How ambiguous is an audio-visual impact?

When two similarly sized white disks are seen to move toward each other, coincide and then move apart, the usual perception is to see the figures as passing despite the perception of an impact being equally plausible. However, if a brief sound is presented at the moment of coincidence this perception is reversed and the objects are seen to collide. Most interpretations of this observation emphasise the role of sound in disambiguating the visual stimulus however the sound induced bounce effect occurs even when the objects unambiguously pass by each other (as for example when one is a disk and the other a square). We will report a series of experiments in which we varied a number of characteristics of the visual stimuli without removing the effect of the sound. It appears that the saliency of a sound is paramount in the perception of an audio-visual impact event

Presentation procedures in measuring emotion laterality via the auditory modality

For more than three decades cognitive neuroscientists have debated the lateralisation of emotion. Currently there are two theories in contention: the right hemisphere hypothesis and the valence hypothesis. The right hemisphere hypothesis is that all emotional are predominantly processed in the right cerebral hemisphere of the human brain while the valence hypothesis is that positive (or approachrelated) and negative (or withdrawal-related) emotions are processing in the left and right cerebral hemispheres respectively. In general listening studies aimed to measure the lateralisation of emotion have employed disparate presentation procedures resulting in inconsistent findings. The current study investigated the affective judgment of simple classes of auditory stimuli (e.g. tonal/atonal melodies) via three presentation procedures: monoaural (i.e. target with no competition), binaural (i.e. target with competing noise), and dichotic (i.e. target with competing melody). Overall, presentation procedure had a direct influence on observed asymmetry highlighting the need for consistency in listening studies aimed to measure the lateralisation of emotion

Spectral matching for abundances of 848 stars of the giant branches of the globular cluster {\omega} Centauri

We present the effective temperatures, surface gravities and abundances of iron, carbon and barium of 848 giant branch stars, of which 557 also have well-defined nitrogen abundances, of the globular cluster {\omega} Centauri. This work used photometric sources and lower resolution spectra for this abundance analysis. Spectral indices were used to estimate the oxygen abundance of the stars, leading to a determination of whether a particular star was oxygen-rich or oxygen-poor. The 557-star subset was analyzed in the context of evolutionary groups, with four broad groups identified. These groups suggest that there were at least four main four periods of star formation in the cluster. The exact order of these star formation events is not yet understood. These results compare well with those found at higher resolution and show the value of more extensive lower resolution spectral surveys. They also highlight the need for large samples of stars when working with a complex object like {\omega} Cen.Comment: 12 pages, 14 figures, accepted for publication in MNRA

LANDSAT and environmental impact in the Paraiba Valley of Sao Paulo

There are no author-identified significant results in this report

Investigation of advanced fault insertion and simulator methods

The cooperative agreement partly supported research leading to the open-literature publication cited. Additional efforts under the agreement included research into fault modeling of semiconductor devices. Results of this research are presented in this report which is summarized in the following paragraphs. As a result of the cited research, it appears that semiconductor failure mechanism data is abundant but of little use in developing pin-level device models. Failure mode data on the other hand does exist but is too sparse to be of any statistical use in developing fault models. What is significant in the failure mode data is that, unlike classical logic, MSI and LSI devices do exhibit more than 'stuck-at' and open/short failure modes. Specifically they are dominated by parametric failures and functional anomalies that can include intermittent faults and multiple-pin failures. The report discusses methods of developing composite pin-level models based on extrapolation of semiconductor device failure mechanisms, failure modes, results of temperature stress testing and functional modeling. Limitations of this model particularly with regard to determination of fault detection coverage and latency time measurement are discussed. Indicated research directions are presented

Causes of death up to 10 years after admissions to hospitals for self-inflicted, drug-related or alcohol-related, or violent injury during adolescence: a retrospective, nationwide, cohort study

Background: Emergency hospital admission with adversity-related injury (ie, self-inflicted, drug-related or alcohol-related, or violent injury) affects 4% of 10–19-year-olds. Their risk of death in the decade after hospital discharge is twice as high as that of adolescents admitted to hospitals for accident-related injury. We established how cause of death varied between these groups. Methods: We did a retrospective, nationwide, cohort study comparing risks of death in five causal groups (suicide, drug-related or alcohol-related, homicide, accidental, and other causes of death) up to 10 years after hospital discharge following adversity-related (self-inflicted, drug-related or alcohol-related, or violent injury) or accident-related (for which there was no recorded adversity) injury. We included adolescents (aged 10–19 years) who were admitted as an emergency for adversity-related or accident-related injury between April 1, 1997, and March 31, 2012. We excluded adolescents who did not have their sex recorded, died during the index admission, had no valid discharge date, or were admitted with injury related to neither adversity nor accidents. We identified admissions for adversity-related or accident-related injury to the National Health Service in England with the International Classification of Diseases-10 codes in Hospital Episode Statistics data, linked to the Office for National Statistics mortality data for England, to establish cause-specific risks of death between the first day and 10 years after discharge, and to compare risks between adversity-related and accident-related index injury after adjustment for age group, socioeconomic status, and chronic conditions. Findings: We identified 1 080 368 adolescents (388 937 [36·0%] girls, 690 546 [63·9%] boys, and 885 [0·1%] adolescents who did not have their sex recorded). Of these adolescents, we excluded 40 549 (10·4%) girls, 56 107 (8·1%) boys, and all 885 without their sex recorded. Of the 333 009 (30·8%) adolescents admitted with adversity-related injury (181 926 [54·6%] girls and 151 083 [45·4%] boys) and 649 818 (60·2%) admitted with accident-related injury (166 462 [25·6%] girls and 483 356 [74·4%] boys), 4782 (0·5%) died in the 10 years after discharge (1312 [27·4%] girls and 3470 [72·6%] boys). Adolescents discharged after adversity-related injury had higher risks of suicide (adjusted subhazard ratio 4·54 [95% CI 3·25–6·36] for girls, and 3·15 [2·73–3·63] for boys) and of drug-related or alcohol-related death (4·71 [3·28–6·76] for girls, and 3·53 [3·04–4·09] for boys) in the next decade than they did after accident-related injury. Although we included homicides in our estimates of 10-year risks of adversity-related deaths, we did not explicitly present these risks because of small numbers and risks of statistical disclosure. There was insufficient evidence that girls discharged after adversity-related injury had increased risks of accidental deaths compared with those discharged after accident-related injury (adjusted subhazard ratio 1·21 [95% CI 0·90–1·63]), but there was evidence that this risk was increased for boys (1·26 [1·09–1·47]). There was evidence of decreased risks of other causes of death in girls (0·64 [0·53–0·77]), but not in boys (0·99 [0·84–1·17]). Risks of suicide were increased following self-inflicted injury (adjusted subhazard ratio 5·11 [95% CI 3·61–7·23] for girls, and 6·20 [5·27–7·30] for boys), drug-related or alcohol-related injury (4·55 [3·23–6·39] for girls, and 4·51 [3·89–5·24] for boys), and violent injury in boys (1·43 [1·15–1·78]) versus accident-related injury. However, the increased risk of suicide in girls following violent injury versus accident-related injury was not significantly increased (adjusted subhazard ratio 1·48 [95% CI 0·73–2·98]). Following each type of index injury, risks of suicide and risks of drug-related or alcohol-related death were increased by similar magnitudes. Interpretation: Risks of suicide were significantly increased after all types of adversity-related injury except for girls who had violent injury. Risks of drug-related or alcohol-related death increased by a similar magnitude. Current practice to reduce risks of harm after self-inflicted injury should be extended to drug-related or alcohol-related and violent injury in adolescence. Prevention should address the substantial risks of drug-related or alcohol-related death alongside risks of suicide. Funding: UK Department of Health