Track and capture of the orbiter with the space station remote manipulator system

Results of the first study using the real-time, man-in-the-loop Systems Engineering Simulator (SES) for track and capture of the Space Shuttle Orbiter with the space station manipulator are presented. The objectives include evaluation of the operational coordination required between the orbiter pilot and the space station manipulator operator, evaluation of the locations and required number of closed-circuit television cameras, and evaluation of the orbiter grapple fixture clearance geometry. The SES is a premium quality real-time facility with full fidelity orbiter and space station crew workstations and cockpits

Full-Potential LMTO: Total Energy and Force Calculations

The essential features of a full potential electronic structure method using Linear Muffin-Tin Orbitals (LMTOs) are presented. The electron density and potential in the this method are represented with no inherent geometrical approximation. This method allows the calculation of total energies and forces with arbitrary accuracy while sacrificing much of the efficiency and physical content of approximate methods such as the LMTO-ASA method.Comment: 25 pages, 2 figures, Workshop on the TB-LMTO method, Monastery of Mont St. Odile, October 4-5, 199

Children’s episodic and generic reports of alleged abuse

With the present data, we explored the relations between the language of interviewer questions, children’s reports, and case and child characteristics in forensic interviews. Results clearly indicated that the type of questions posed by interviewers – either probing generic or episodic features of an event – was related to the specificity of information reported by children. Further, interviewers appeared to adjust their questioning strategies based on the frequency of the alleged abuse. Children alleging single instances of abuse were asked more episodic questions than those alleging multiple abuses. In contrast, children alleging multiple incidents of abuse were asked a greater proportion of generic questions. Given that investigators often seek forensically-relevant episodic information, it is recommended that training for investigators focus on recognition of prompt selection tendencies and developing strategies for posing non-suggestive, episodically focused questions

Physiological demands of fencing: A narrative review

Background and Aim Fencers compete over long competition days (9-11 hours) wearing full body protective clothing whilst performing high-intensity explosive movements interspersed with low intensity preparatory or recovery movements. Therefore the aim of this review is to provide contemporary perspectives of the literature discussing the physiological and thermoregulatory demands of fencing to inform training, competition, and recovery practices. Methods Research articles were searched through three online databases (Pubmed, SPORTDiscus, and Google Scholar; 1985-2022) and included results discussing physiological demands for all three weapons (epée, foil, and sabre). Results The physiological demands of fencing performance are high and increase as fencers move from Poule fights to knockout Direct Elimination fights. Fencers compete at 75-100% of maximum heart rate, and ~75% maximal oxygen consumption in Direct Elimination fights. Fencing performance is reliant on the phosphocreatine and aerobic energy systems as shown through low blood lactate concentrations. Considerable variation in distance covered during competition is generally reported (i.e., 435 to 1652m in Direct Elimination fights). Despite fencers competing in full body protective clothing with a potentially large thermoregulatory challenge only one study has examined thermoregulatory responses during fencing whereby fencers’ gastrointestinal temperature can peak at >39°C. Conclusions Future research highlighted by the findings of this review includes studies of all weapon types especially foil and sabre, during actual competitive environments. Thermoregulatory responses of fencing need to be determined including measures of skin temperature, mask temperature (as a measure of micro-climates) and thermal sensation, allowing for appropriate cooling strategies to be applied between fights to maintain or improve performance. Practical Applications A greater understanding of the physiological demands of fencing performance will allow athletes, coaches, and practitioners to design training to prepare athletes for competition and allow fencing specific protocols to be developed to determine recovery strategies within fencing

A smoothing algorithm using cubic spline functions

Two algorithms are presented for smoothing arbitrary sets of data. They are the explicit variable algorithm and the parametric variable algorithm. The former would be used where large gradients are not encountered because of the smaller amount of calculation required. The latter would be used if the data being smoothed were double valued or experienced large gradients. Both algorithms use a least-squares technique to obtain a cubic spline fit to the data. The advantage of the spline fit is that the first and second derivatives are continuous. This method is best used in an interactive graphics environment so that the junction values for the spline curve can be manipulated to improve the fit

Electron beam fluorescence measurements in the Boeing hypersonic shock tunnel

The Calspan electron beam fluorescence (EBF) measurement system is described along with the results of measurements made in hypersonic flow. Numerous self-emitting metallic species were identified, many of which may be associated with an aging/erosion process within the B30HST. Because there were only 16 tunnel runs, it was only possible to obtain spectral measurements over a limited range of wavelengths and time sampling periods. Many spectral features of the flow remain uninvestigated. Because flow self-emission is important to all optical diagnostic techniques, it is recommended that additional spectral studies by performed. The three electron beam-excited species that were identified are nitrogen, helium, and nitric oxide. The high metallic radiation background interfered with attempts to obtain the time-wise variation of N2 density and He radiation with the optical fiber/PMT channels. In the case of the N2 density measurements the result of interference was increased uncertainty. Unfortunately, the interference caused the time-wise He measurements to fail completely. It is recommended that the electron beam be modulated to provide discrimination against the background radiation in future N2 density measurements. Careful data reduction produced useful measurements of N2 vibrational temperature, even though the high background from metallic species significantly increased measurement uncertainty. Perhaps the recommended additional spectral studies would reveal N2(+) First Negative System band-pair regions having less background. Detection of the He arrival was easily accomplished with the spectrometer/array detector system. Because of this, it is recommended that this means of detecting He arrival be used in the future. With proper calibrations of the system an He number density could be obtained. Although the flow conditions were out of limits for the run in which the NO spectrum was recorded, the usefulness of the NO spectrum for determination of free-stream rotational temperature was demonstrated and should be exploited in future experiments. Indeed, based on the strong NO signals, it is recommended that lower resolution NO spectra be obtained to provide a measure of NO vibrational temperature in the same manner that the N2 temperature was obtained

Does Inflation Provide Natural Initial Conditions for the Universe?

If our universe underwent inflation, its entropy during the inflationary phase was substantially lower than it is today. Because a low-entropy state is less likely to be chosen randomly than a high-entropy one, inflation is unlikely to arise through randomly-chosen initial conditions. To resolve this puzzle, we examine the notion of a natural state for the universe, and argue that it is a nearly-empty spacetime. If empty space has a small vacuum energy, however, inflation can begin spontaneously in this background. This scenario explains why a universe like ours is likely to have begun via a period of inflation, and also provides an origin for the cosmological arrow of time.Comment: Submitted to Gravity Research Foundation Essay Competition; based on hep-th/041027

Survival of fossils under extreme shocks induced by hypervelocity impacts

Experimental data are shown for survival of fossilized diatoms undergoing shocks in the GPa range. The results were obtained from hypervelocity impact experiments which fired fossilized diatoms frozen in ice into water targets. After the shots, the material recovered from the target water was inspected for diatom fossils. Nine shots were carried out, at speeds from 0.388 to 5.34?km?s?1, corresponding to mean peak pressures of 0.2–19?GPa. In all cases, fragmented fossilized diatoms were recovered, but both the mean and the maximum fragment size decreased with increasing impact speed and hence peak pressure. Examples of intact diatoms were found after the impacts, even in some of the higher speed shots, but their frequency and size decreased significantly at the higher speeds. This is the first demonstration that fossils can survive and be transferred from projectile to target in hypervelocity impacts, implying that it is possible that, as suggested by other authors, terrestrial rocks ejected from the Earth by giant impacts from space, and which then strike the Moon, may successfully transfer terrestrial fossils to the Moon