Space time neural networks for tether operations in space

A space shuttle flight scheduled for 1992 will attempt to prove the feasibility of operating tethered payloads in earth orbit. due to the interaction between the Earth's magnetic field and current pulsing through the tether, the tethered system may exhibit a circular transverse oscillation referred to as the 'skiprope' phenomenon. Effective damping of skiprope motion depends on rapid and accurate detection of skiprope magnitude and phase. Because of non-linear dynamic coupling, the satellite attitude behavior has characteristic oscillations during the skiprope motion. Since the satellite attitude motion has many other perturbations, the relationship between the skiprope parameters and attitude time history is very involved and non-linear. We propose a Space-Time Neural Network implementation for filtering satellite rate gyro data to rapidly detect and predict skiprope magnitude and phase. Training and testing of the skiprope detection system will be performed using a validated Orbital Operations Simulator and Space-Time Neural Network software developed in the Software Technology Branch at NASA's Lyndon B. Johnson Space Center

Learning characteristics of a space-time neural network as a tether skiprope observer

The Software Technology Laboratory at the Johnson Space Center is testing a Space Time Neural Network (STNN) for observing tether oscillations present during retrieval of a tethered satellite. Proper identification of tether oscillations, known as 'skiprope' motion, is vital to safe retrieval of the tethered satellite. Our studies indicate that STNN has certain learning characteristics that must be understood properly to utilize this type of neural network for the tethered satellite problem. We present our findings on the learning characteristics including a learning rate versus momentum performance table

Exercise as a psychological therapy in obese adolescents.

?Childhood obesity has reached epidemic proportions globally (Wang & Lobstein, 2006). Obesity has been linked with psychopathology in adolescents seeking treatment (Zametkin, Zoon, Klein & Munson, 2004). To avoid serious health consequences in adulthood, the high incidence of psychopathology in this population needs to be addressed. Exercise has the potential to improve both physical and psychological health simultaneously; however, there is a lack of research investigating the effects of exercise upon psychopathology in obese young people. Therefore, this thesis provides an examination of the effects of a supervised exercise therapy intervention upon psychopathology related outcomes in obese adolescents using a randomised controlled trial (RCT) method. The primary trial hypothesis was that exercise therapy would lead to improvements in participants' physical self-esteem and reductions in psychopathology. Two qualitative studies explored obese adolescents' experiences of participation in an exercise therapy intervention and a further study investigated their ratings of perceived exertion (RPE) during exercise.The population sample consisted of 81 obese (body mass index (BMI) > 2.5 SDS, adult equivalent BMI of > 30) adolescents aged between 11-16 years who had been referred to a children's hospital for evaluation of obesity or responded to a community advert. Participants were randomised to exercise therapy, an equal contact exercise-placebo intervention or usual care control. Intervention participants attended three one-to-one sessions per week, over eight-weeks and then completed a home programme for six-weeks. Participants were interviewed at the end of the eight-week intervention and again after the home programme. Outcomes included self-perceptions (self-esteem), depression, affect, physical activity and BMI. Repeated measures mixed analysis of covariance (controlling for baseline scores) revealed significant differences in physical self-worth, associated measures of self-esteem and physical activity over time in favour of the exercise therapy condition. There were no significant differences in BMI. Findings from the qualitative studies revealed that obese adolescents were happier than when they began the programme, expressed surprise at how much they were capable of achieving in terms of exercise and felt empowered to continue to exercise over the long-term. Some felt that the intervention was not long enough and many of the common barriers to exercise typically reported by other young people, such as time, were cited at interview. Obese adolescents reported RPE during exercise to be significantly greater for the lower limbs compared with aerobic exertion.This study is the first RCT to demonstrate that a brief supervised exercise therapy intervention has the potential to significantly improve psychopathology related outcomes and increase physical activity in obese adolescents, relative to usual care. Findings indicate that obese children can successfully perform short intermittent bouts of structured exercise, given the opportunity, and that physical activity can contribute to the enhancement of their psychological and social well-being. Results also suggest that obese adolescents find prolonged bouts of exercise fatiguing in the lower limbs particularly which underlines the critical need for future interventions aimed at treating obesity to be aware of the importance of assessing ratings of perceived exertion during exercise. It is hoped that this thesis will generate additional research interest and concern about the psychopathology of young people who are obese. In particular, raise awareness of the importance of assessing the efficacy of obesity treatments in relation to psychopathology outcomes in future trials. It is also hoped that the exercise therapy guidelines provided here would inform health practitioners in the delivery of exercise therapy and highlight the potential contribution exercise therapy could make to the treatment of childhood obesity in pragmatic environments such as the NHS

Space Suit Radiator Performance in Lunar and Mars Environments

During an ExtraVehicular Activity (EVA), both the heat generated by the astronaut's metabolism and that produced by the Portable Life Support System (PLSS) must be rejected to space. The heat sources include the heat of adsorption of metabolic CO2, the heat of condensation of water, the heat removed from the body by the liquid cooling garment and the load from the electrical components. Although the sublimator hardware to reject this load weighs only 1.58 kg (3.48 lbm), an additional 3.6 kg (8 lbm) of water are loaded into the unit, most of which is sublimated and lost to thus become the single largest expendable during an eight hour EVA. We can significantly reduce the amount of expendable water consumed in the sublimator by using a radiator to reject heat from the Astronaut during an EVA. Last year we reported on the design and initial operational assessment tests of our novel radiator designated the Radiator And Freeze Tolerant heat eXchanger (RAFT-X). Herein, we report on tests conducted in the NASA Johnson Space Center Chamber E Thermal Vacuum Test Facility. Up to 260 W (900 Btu/h) of heat were rejected in Lunar and Mars environments with temperatures as cold as -170 C (- 275 F). Further, the RAFT-X endured several freeze / thaw cycles and in fact, the heat exchanger was completely frozen three times without any apparent damage to the unit

Effects of a pragmatic lifestyle intervention for reducing body mass in obese adults with obstructive sleep apnoea: a randomised controlled trial

This study investigated the effects of a pragmatic lifestyle intervention in obese adults with continuous positive airway pressure-treated obstructive sleep apnoea hypopnoea syndrome (OSAHS). Sixty patients were randomised 1 : 1 to either a 12-week lifestyle intervention or an advice-only control group. The intervention involved supervised exercise sessions, dietary advice, and the promotion of lifestyle behaviour change using cognitive-behavioural techniques. Outcomes were assessed at baseline (week 0), intervention end-point (week 13), and follow-up (week 26). The primary outcome was 13-week change in body mass. Secondary outcomes included anthropometry, blood-borne biomarkers, exercise capacity, and health-related quality of life. At end-point, the intervention group exhibited small reductions in body mass (−1.8 [−3.0, −0.5] kg; P = 0.007) and body fat percentage (−1 [−2, 0]%; P = 0.044) and moderate improvements in C-reactive protein (−1.3 [−2.4, −0.2] mg·L−1; P = 0.028) and exercise capacity (95 [50, 139] m; P <0.001 ). At follow-up, changes in body mass (−2.0 [−3.5, −0.5] kg; P = 0.010), body fat percentage (−1 [−2, 0]%; P = 0.033), and C-reactive protein (−1.3 [−2.5, −0.1] mg·L−1; P = 0.037 ) were maintained and exercise capacity was further improved (132 [90, 175] m; P <0.001). This trial is registered with ClinicalTrials.gov NCT01546792

Induction heating coupler and annealer

An induction heating device includes a handle having a hollow interior and two opposite ends, a wrist connected to one end of the handle, a U-shaped pole piece having- two spaced apart ends, a tank circuit including an induction coil wrapped around the pole piece and a capacitor connected to the induction coil, a head connected to the wrist and including a housing for receiving the U-shaped pole piece, the two spaced apart ends of the pole piece extending outwardly beyond the housing, and a power source connected to the tank circuit. When the tank circuit is energized and a susceptor is placed in juxtaposition to the ends of the U-shaped pole piece, the susceptor is heated by induction heating due to a magnetic flux passing between the two ends of the pole piece

Are Exercise Referral Schemes Associated With an Increase in Physical Activity? Observational Findings Using Individual Patient Data Meta-Analysis From the National Referral Database

Objectives: To examine if exercise referral schemes (ERSs) are associated with meaningful changes in physical activity in a large cohort of individuals throughout England, Scotland, and Wales from The National Referral Database. Methods: Data were obtained from 5246 participants from 12 different ERSs, lasting 6–12 weeks. The preexercise referral scheme and changes from the preexercise to the postexercise referral scheme in self-reported International Physical Activity Questionnaire scores were examined. A 2-stage individual patient data meta-analysis was used to generate the effect estimates. Results: For the pre-ERS metabolic equivalent (MET) minutes per week, the estimate (95% confidence interval [CI]) was 676 MET minutes per week (539 to 812). For the change in MET minutes per week, the estimate (95% CI) was an increase of 540 MET minutes per week (396 to 684). Changes in the total PA levels occurred as a result of increases in vigorous activity of 17 minutes (95% CI, 9 to 24), increases in moderate activity of 29 minutes (95% CI, 22 to 36), and reductions in sitting of −61 minutes (95% CI, −78 to −43), though little change in walking (−5 min; 95% CI, −14 to 5) was found. Conclusions: Most participants undergoing ERSs are already “moderately active.” Changes in PA behavior associated with participation are through increased moderate to vigorous PA and reduced sitting. However, this was insufficient to change the International Physical Activity Questionnaire category, and the participants were still “moderately active.

The Neoproterozoic Keraf Suture in NE Sudan: Sinistral Transpression along the Eastern Margin of West Gondwana

The Keraf Suture, formed during the Neoproterozoic consolidation of Gondwana, is a ~500 km long, ~50 km wide, N-trending suture between the Neoproterozoic Arabian-Nubian Shield in the east and the older Nile Craton to the west. The Keraf Suture is superimposed on E- and NE-trending structures on both sides. The northern part of the suture is dominated by N-trending, upright folds, whereas the southern part is characterized by N- and NNW-trending, sinistral, strike-slip faults. A major antiform defines a structural divide between the northern and southern parts of the suture. 40Ar/39Ar ages on biotite and hornblendes separated from a deformed granitic body indicate that the sinistral movement along the N- and NNW-trending faults took place at ~580 Ma. The difference in structural styles along strike is due to formation of the Keraf Suture by sinistral transpression, which accompanied early NW-SE oblique collision between East and West Gondwana at ~650-600 Ma and terminal collision at ~580 Ma

Induction heating coupler

An induction heating device includes a handle having a hollow interior and two opposite ends, a wrist connected to one end of the handle, a U-shaped pole piece having two spaced apart ends, a tank circuit including an induction coil wrapped around the pole piece and a capacitor connected to the induction coil, a head connected to the wrist and including a housing for receiving the U-shaped pole piece, the two spaced apart ends of the pole piece extending outwardely beyond the housing, and a power source connected to the tank circuit. When the tank circuit is energized and a susceptor is placed in juxtaposition to the ends of the U-shaped pole piece, the susceptor is heated by induction heating due to magnetic flux passing between the two ends of the pole piece