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61.
Wright Laboratory Avionics Directorate is helping to assemble a team of defense and civilian researchers to transition defense avionics and related technologies to the medical community with the goal of improving the Computer Assisted Minimally invasive Surgery (CAMIS) concept. Key partners include Ohio Aerospace Institute (OAI), a not-for-profit state-chartered agency, Cleveland Clinic Foundation hospital, and Picker International, medical equipment manufacturer. The CAMIS concept is in response to the fact that despite technical advances, most excision surgeries are exploratory rather than remedial. As a result, large incisions are required so the surgeon can first search for the “target” tissue and then, more cutting is needed to remove or destroy the “target”. CAMIS is an opportunity to transition defense avionics technologies to help tackle a critical non-defense issue on the national agenda, health care 相似文献
62.
63.
D. J. Williams 《Space Science Reviews》1985,42(3-4):375-396
The development of currents within an arbitrary distribution of particles trapped in the geomagnetic field is described. These currents combine to form the earth's ring current and thus are responsible for the worldwide depressions of surface magnetic field strength during periods of magnetic activity known as magnetic storms. Following a brief review of trapped particle motion in magnetic fields, ring current development is described and presented in terms of basic field and particle distribution parameters. Experimental observations then are presented and discussed within the theoretical framework developed earlier. New results are presented which, in the area of composition and charge state observations, hold high promise in solving many long standing ring current problems. Finally, available experimental results will be used to assess our present understanding as to ring current sources, generation, and dissipation. 相似文献
64.
H. Steinle H. Bloemen W. Collmar R. Diehl W. Hermsen G. Lichti M. McConnell J. Ryan V. Schnfelder G. Stacy A. W. Strong B. N. Swanenburg M. Varendorff O. R. Williams 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1993,13(12):731-734
During the first part of the COMPTON Gamma Ray Observatory sky survey, COMPTEL has detected the quasars 3C273 and 3C279 and the radio galaxy Centaurus A. This paper summarizes the preliminary findings and gives an upper limit on the MeV flux of the Seyfert galaxy NGC4151. 相似文献
65.
Amongst its complement of particles and fields instruments, the Galileo spacecraft carries an Energetic Particles Detector (EPD) designed to measure the characteristics of particle populations important in determining the size, shape, and dynamics of the Jovian magnetosphere. To do this the EPD provides 4 angular coverage and spectral measurements for Z 1 ions from 20 keV to 55 MeV, for electrons from 15 keV to > 11 MeV, and for the elemental species helium through iron from approximately 10 keV nucl-1 to 15 MeV nucl-1. Two bi-directional telescopes, mounted on a stepping platform, employ magnetic deflection, energy loss versus energy, and time-of-flight techniques to provide 64 rate channels and pulse height analysis of priority selected events. The EPD data system provides a large number of possible operational modes from which a small number will be selected to optimize data collection during the many encounter and cruise phases of the mission. The EPD employs a number of safeing algorithms that are to be used in the event that its self-checking procedures indicate a problem. The EPD has demonstrated its operational flexibility throughout the long evolution of the Galileo program by readily accommodating a variety of secondary mission objectives occasioned by the changing mission profile, such as the Venus flyby and the Earth 1 and 2 encounters. To date the EPD performance in flight has been nominal. In this paper we describe the instrument and its operation. 相似文献
66.
David Auslander Joshua Cermenska Gregory Dalton Mauricio de la Pena C. K. H. Dharan William Donokowski Robert Duck Jonghak Kim David Pankow Alec Plauche Mustapha Rahmani Stephen Sulack Tien Fak Tan Paul Turin Tyler Williams 《Space Science Reviews》2008,141(1-4):185-211
The five “Time History of Events and Macroscale Interactions during Substorms” (THEMIS) micro-satellites launched on a common carrier by a Delta II, 7925 heavy, on February 17, 2007. This is the fifth launch in the NASA MeDIum class EXplorer (MIDEX) program. In the mission proposal the decision was made to have the University of California Berkeley Space Sciences Laboratory (UCB-SSL) mechanical engineering staff provide all of the spacecraft appendages, in order to meet the short development schedule, and to insure compatibility. This paper describes the systems engineering, design, development, testing, and on-orbit deployment of these boom systems that include: the 1 and 2 meter carbon fiber composite magnetometer booms, the 40 and 50 m tip to tip orthogonal spin-plane wire boom pairs, and the 6.3 m dipole stiff axial booms. 相似文献
67.
A. Connors W. Collmar L. Hanlon W. Hermsen R. M. Kippen L. Kuiper M. McConnell J. Ryan V. Schnfelder M. Varendorff O. R. Williams C. Winkler 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1993,13(12):715-718
The COMPTEL experiment on GRO images 0.7 – 30 MeV celestial gamma-radiation that falls within its 1 steradian field of view. During the first fifteen months in orbit, preliminary localizations from BATSE triggers indicated that about 1 in 6 cosmic events could have fallen within COMPTEL's field of view. We summarize work on the brightest of these gamma-ray bursts and present new position constraints for GRB 911118 and GRB 920622. 相似文献