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11.
Management of health problems in limited resource environments, including spaceflight, faces challenges in both available equipment and personnel. The medical support for spaceflight outside Low Earth Orbit is still being defined; ultrasound (US) imaging is a candidate since trials on the International Space Station (ISS) prove that this highly informative modality performs very well in spaceflight. Considering existing estimates, authors find that US could be useful in most potential medical problems, as a powerful factor to mitigate risks and protect mission. Using outcome-oriented approach, an intuitive and adaptive US image catalog is being developed that can couple with just-in-time training methods already in use, to allow non-expert crew to autonomously acquire and interpret US data for research or diagnosis.The first objective of this work is to summarize the experience in providing imaging expertise from a central location in real time, enabling data collection by a minimally trained operator onsite. In previous investigations, just-in-time training was combined with real-time expert guidance to allow non-physician astronauts to perform over 80 h of complex US examinations on ISS, including abdominal, cardiovascular, ocular, musculoskeletal, dental/sinus, and thoracic exams. The analysis of these events shows that non-physician crew-members, after minimal training, can perform complex, quality US examinations. These training and guidance methods were also adapted for terrestrial use in professional sporting venues, the Olympic Games, and for austere locations including Mt. Everest.The second objective is to introduce a new imaging support system under development that is based on a digital catalog of existing sample images, complete with image recognition and acquisition logic and technique, and interactive multimedia reference tools, to guide and support autonomous acquisition, and possibly interpretation, of images without real-time link with a human expert. In other words, we are attempting to replace, to the extent possible, expert guidance by guidance from a digital information resource. This is a next logical phase of the authors’ sustained effort to make US imaging available to sites lacking proper expertise. This effort will benefit NASA as the agency plans to develop future human exploration programs requiring increased medical autonomy. The new system will be readily adaptable to terrestrial medicine including emergency, rural, and military applications.  相似文献   
12.
Reliable electro-mechanical actuators in aircraft   总被引:1,自引:0,他引:1  
There is a general trend in the aerospace industry toward increasing the use of electrically-powered equipment. This trend is usually referred to as "Power-by-Wire" in the "More Electric Aircraft" (MEA) concept and it leads, among others, to the substitution of hydraulic actuators by Electro-Mechanical Actuators (EMA). Its benefits are a decrease in maintenance effort and weight, and an increase in efficiency. However, jamming case obstacles stop the massive use of EMAs in flight-control actuators. The aim herein is to introduce the safety needs of electro-mechanical actuators in aircraft applications, and Its major goal is to present the suitability and reliability of such actuator systems, including electric motors and power converters.  相似文献   
13.
The trust literature emphasizes trust in automation, thus neglecting the interpersonal aspects of how distributed personnel develop trust. Interpersonal trust represents the willingness of individuals to accept vulnerabilities from the actions of others. Vulnerability is a critical aspect of trust research, yet few studies have manipulated vulnerability. Non-verbal cues may have an influence on the trust process, suggesting that features of collaborative tools may influence how individuals build trust. The present study will implement a 3 x 4 mixed design. Participants will select a convoy route based on: * 1) graphical displays of enemy zones and historical Improvised Explosive Device (lED) occurrences; * 2) route parameters (e.g., fuel required); and * 3) information from a local expert. Vulnerability will be manipulated by altering the frequency of TEDs and the location of "red forces" to create low, moderate, and high vulnerability conditions (within subjects factor). Information from local experts will be presented via one of four conditions: * 1) audio/video with low emotion; * 2) audio/video with high emotion; ,, 3) audio only; and * 4) chat (between subjects factor). Findings from this research will support the development of new collaborative tools for the Command and Control (C2) domain.  相似文献   
14.
Introduction: This joint US–Russian work aims to establish a methodology for assessing cardiac function in microgravity in association with manipulation of central circulating volume. Russian Braslet-M (Braslet) occlusion cuffs were used to temporarily increase the volume of blood in the lower extremities, effectively reducing the volume in central circulation. The methodology was tested at the International Space Station (ISS) to assess the volume status of crewmembers by evaluating the responses to application and release of the cuffs, as well as to modified Valsalva and Mueller maneuvers. This case study examines the use of tissue Doppler (TD) of the right ventricular (RV) free wall. Results: Baseline TD of the RV free wall without Braslet showed early diastolic E′ (16 cm/s), late diastolic A′ (14 cm/s), and systolic S′ (12 cm/s) velocities comparable with those in normal subjects on Earth. Braslet application caused 50% decrease of E′ (8 cm/s), 45% increase of A′, and no change to S′. Approximately 8 beats after the Braslet release, TD showed E′ of 8 cm/s, A′ of 12 cm/s, and S′ of 13 cm/s. At this point after release, E′ did not recover to baseline values while l A′ and S′ did recover. The pre-systolic cross-sectional area of the internal jugular vein without Braslet was 1.07 cm2, and 1.13 cm2 10 min after the Braslet was applied. The respective cross-sectional areas of the femoral vein were 0.50 and 0.54 cm2. The RV myocardial performance Tei index was calculated by dividing the sum of the isovolumic contraction time and isovolumic relaxation time by the ejection time ((IVCT+IVRT)/ET); baseline and Braslet-on values for Tei index were 0.25 and 0.22, respectively. Braslet Tei indices are within normal ranges found in healthy terrestrial subjects and temporarily become greater than 0.4 during the dynamic Braslet release portion of the study. Conclusions: TD modality was successfully implemented in space flight for the first time. TD of RV revealed that the Braslet influenced cardiac preload and that fluid was sequestered in the lower extremity interstitial and vascular space after only 10 min of application. This report demonstrates that Braslet application has an effect on RV physiology in long-duration space flight based on TD, and that this effect is in part due to venous hemodynamics.  相似文献   
15.
A new low-power instrument to measure meteorological parameters has been developed. The instrument is based on an intelligent data cruncher concept: Fast sensor data rates are stored and process to yield a variety of answers for each parameter, at slower data rates, as appropriate. Special methods are used to achieve these results with an average current drain of under one mA, including sensors. Sampling rates and processing algorithms are designed to correct for swaying ocean-deployed buoys. A modular approach to design allows many types of sensors to be accommodated and permits data dissemination to a variety of destinations; data is available for real-time transmission or for internal archiving. The Weather Station's high-capacity internal data storage system, coupled with its fast data acquisition rates, enable the instrument to be used for air turbulence measurements.  相似文献   
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Clinton  J.  Giardini  D.  Böse  M.  Ceylan  S.  van Driel  M.  Euchner  F.  Garcia  R. F.  Kedar  S.  Khan  A.  Stähler  S. C.  Banerdt  B.  Lognonne  P.  Beucler  E.  Daubar  I.  Drilleau  M.  Golombek  M.  Kawamura  T.  Knapmeyer  M.  Knapmeyer-Endrun  B.  Mimoun  D.  Mocquet  A.  Panning  M.  Perrin  C.  Teanby  N. A. 《Space Science Reviews》2018,214(8):1-51
Space Science Reviews - In recent decades, volcanic and cryovolcanic activity on moons within the Solar System has been recognised as an important source of cosmic dust. Two moons, Jupiter’s...  相似文献   
19.
Panning  Mark P.  Lognonné  Philippe  Bruce Banerdt  W.  Garcia  Raphaël  Golombek  Matthew  Kedar  Sharon  Knapmeyer-Endrun  Brigitte  Mocquet  Antoine  Teanby  Nick A.  Tromp  Jeroen  Weber  Renee  Beucler  Eric  Blanchette-Guertin  Jean-Francois  Bozdağ  Ebru  Drilleau  Mélanie  Gudkova  Tamara  Hempel  Stefanie  Khan  Amir  Lekić  Vedran  Murdoch  Naomi  Plesa  Ana-Catalina  Rivoldini  Atillio  Schmerr  Nicholas  Ruan  Youyi  Verhoeven  Olivier  Gao  Chao  Christensen  Ulrich  Clinton  John  Dehant  Veronique  Giardini  Domenico  Mimoun  David  Thomas Pike  W.  Smrekar  Sue  Wieczorek  Mark  Knapmeyer  Martin  Wookey  James 《Space Science Reviews》2017,211(1-4):611-650
Space Science Reviews - The InSight lander will deliver geophysical instruments to Mars in 2018, including seismometers installed directly on the surface (Seismic Experiment for Interior Structure,...  相似文献   
20.
The Atacama Desert has long been considered a good Mars analogue for testing instrumentation for planetary exploration, but very few data (if any) have been reported about the geomicrobiology of its salt-rich subsurface. We performed a Mars analogue drilling campaign next to the Salar Grande (Atacama, Chile) in July 2009, and several cores and powder samples from up to 5?m deep were analyzed in situ with LDChip300 (a Life Detector Chip containing 300 antibodies). Here, we show the discovery of a hypersaline subsurface microbial habitat associated with halite-, nitrate-, and perchlorate-containing salts at 2?m deep. LDChip300 detected bacteria, archaea, and other biological material (DNA, exopolysaccharides, some peptides) from the analysis of less than 0.5?g of ground core sample. The results were supported by oligonucleotide microarray hybridization in the field and finally confirmed by molecular phylogenetic analysis and direct visualization of microbial cells bound to halite crystals in the laboratory. Geochemical analyses revealed a habitat with abundant hygroscopic salts like halite (up to 260?g kg(-1)) and perchlorate (41.13?μg g(-1) maximum), which allow deliquescence events at low relative humidity. Thin liquid water films would permit microbes to proliferate by using detected organic acids like acetate (19.14?μg g(-1)) or formate (76.06?μg g(-1)) as electron donors, and sulfate (15875?μg g(-1)), nitrate (13490?μg g(-1)), or perchlorate as acceptors. Our results correlate with the discovery of similar hygroscopic salts and possible deliquescence processes on Mars, and open new search strategies for subsurface martian biota. The performance demonstrated by our LDChip300 validates this technology for planetary exploration, particularly for the search for life on Mars.  相似文献   
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