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991.
The IBEX mission includes a comprehensive Education and Public Outreach (E/PO) program that develops programs and products in exciting themes from astronomy and space physics. With the active involvement of the Principal Investigator and several science team partners, it is overseen and implemented by the Adler Planetarium & Astronomy Museum. The program includes an internationally distributed planetarium show with accompanying informal education materials that are also accessible to individuals with special needs; a national Space Science Core Curriculum for grades 6–8 in collaboration with other NASA missions; a professional development program for teachers; and workshops that engage Hispanic and Native American students. Materials are made available for download or for order via the IBEX website: http://www.ibex.swri.edu/. Our program is developed, implemented and monitored for effectiveness by organizations with proven capabilities and experience in their respective areas of E/PO. This paper describes these program elements in detail and includes the rationale and design process for this E/PO program.  相似文献   
992.
A mathematical model for the annular gas-liquid mixture flow in the cylindrical channel is described. The influence of an upward turbulent gas flow on the downward liquid film is considered. The problem is numerically solved and the calculation results are compared with the experimental data.  相似文献   
993.
The results of analyzing axisymmetric forced vibrations of an elastic circular sandwich plate connected with an elastic foundation under different surface loads are presented. The hypotheses of a broken normal are accepted to describe the kinematics of a package that is nonsymmetrical over the thickness. The analytical solutions of a problem for plates with a light filler are obtained and numerical analysis is carried out.  相似文献   
994.
We consider some general problems of improving the strength characteristics of folded cores as well as the corresponding techniques for modifying the core material polymer surfaces with the use of nanotechnologies and the “mass-strength” criteria.  相似文献   
995.
We present the results of experimental studies of the fuel hydrogen additive influence on the characteristics of a gas-piston engine converted for operation by natural gas under changes of an ignition advance angle (IAA). The results of investigations were used to determine the influence of the hydrogen additive on the effective engine efficiency and fuel consumption under IAA changes.  相似文献   
996.
Investigations of blood pressure, heart rate (HR), and heart rate variability (HRV) during long term space flights on board the “ISS” have shown characteristic changes of autonomic cardiovascular control. Therefore, alterations of the autonomic nervous system occurring during spaceflight may be responsible for in- and post-flight disturbances. The device “Pneumocard” was developed to further investigate autonomic cardiovascular and respiratory function aboard the ISS. The hard-software diagnostic complex “Pneumocard” was used during in-flight experiment aboard ISS for autonomic function testing. ECG, photoplethysmography, respiration, transthoracic bioimpedance and seismocardiography were assessed in one male cosmonaut (flight lengths six month). Recordings were made prior to the flight, late during flight, and post-flight during spontaneous respiration and controlled respiration at different rates.HR remained stable during flight. The values were comparable to supine measurements on earth. Respiratory frequency and blood pressure decreased during flight. Post flight HR and BP values increased compared to in-flight data exceeding pre-flight values. Cardiac time intervals did not change dramatically during flight. Pulse wave transit time decreased during flight. The maximum of the first time derivative of the impedance cardiogram, which is highly correlated with stroke volume was not reduced in-flight.Our results demonstrate that autonomic function testing aboard the ISS using “Pneumocard” is feasible and generates data of good quality. Despite the decrease in BP, pulse wave transit time was found reduced in space as shown earlier. However, cardiac output did not decrease profoundly in the investigated cosmonaut.Autonomic testing during space flight detects individual changes in cardiovascular control and may add important information to standard medical control. The recent plans to support a flight to Mars, makes these kinds of observations all the more relevant and compelling.  相似文献   
997.
The Venus Express mission is the European Space Agency's (ESA) first spacecraft at Venus. It was launched in November 2005 by a Soyuz–Fregat launcher and arrived at Venus in April 2006. The mission covers a broad range of scientific goals including physics, chemistry, dynamics and structure of the atmosphere as well as atmospheric interaction with the surface and several aspects of the surface itself. Furthermore, it investigates the plasma environment and interaction of the solar wind with the atmosphere and escape processes.One month after the arrival at Venus the Venus Express spacecraft started routine science operations. Since then Venus Express has been observing Venus every day for more than one year continuously making new discoveries.In order to ensure that all the science objectives are fulfilled the Venus Express Science Operations Centre (VSOC) has the task of coordinating and implementing the science operations for the mission. During the first year of Venus observations the VSOC and the experiment teams gained a lot of experience in how to make best use of the observation conditions and payload capabilities. While operating the spacecraft in orbit we also acquired more knowledge on the technical constraints and more insight in the science observations and their results.As the nominal mission is coming to an end, the extended mission will start from October 2007. The Extended Science Mission Plan was developed taking into account the lessons learned. At the same time new observations were added along with specific fine-tuned observations in order to complete the science objectives of the mission.This paper will describe how the previous observations influence the current requirements for the observations around Venus today and how they influence the observations in the mission extension. Also it will give an overview of the Extended Science Mission Plan and its challenges for the future observations.  相似文献   
998.
We present the results of processing three 256-min series of observations of quasi-periodic oscillations of the field of line-of-sight velocities in three sunspots. The Doppler shifts were determined simultaneously for six spectral lines formed at different heights in the solar atmosphere. In addition to the well-known high-frequency (periods of 3–5 min) oscillations, a band of low-frequency oscillations with periods of 60–80 min is revealed in the spectra of the sunspot umbra and magnetic elements located in immediate proximity of the sunspot. Unlike the short-period modes, the power of the long-period mode of line-of-sight velocity oscillations in the sunspot decreases sharply with height: these oscillations are distinctly seen in the line formed at a height of 200 km and almost are not seen in the line with the formation height of 500 km. This is indicative of different physical nature of the short-period and long-period oscillations of a sunspot. If the former are caused by slow magnetosonic waves within the field tube of the spot, the latter are representative of global vertical-radial oscillations of a magnetic element (spot, pore) as a whole near the position of a stable equilibrium.  相似文献   
999.
The results of numerical simulation of the general circulation in the Titan’s atmosphere at heights from 0 to 250 km are presented, obtained using a new model based on numerical solution of complete equations of motion of viscous compressible gas at the temperature distribution given by an empirical model. The model uses no hydrostatic equation and, as compared with traditional models, has higher resolution in vertical and over horizon. The results presented differ from results of other models and agree with the vertical profile of the zonal component of wind velocity measured by the Huygens spacecraft. Interpretation of this profile is given, including its main peculiarity consisting in a nonmonotonic behavior at heights from 60 to 75 km.  相似文献   
1000.
On the basis of generalization of the results of extensive trajectory calculations for trial charged particles moving in the geomagnetic field the method of calculation of effective vertical cutoff rigidity, taking into account the values of K p -index and local time, is developed. The IGRF and Tsyganenko-89 models are used for the geomagnetic field. A comparison of the results of model simulations with the experimental data on penetration of charged particles into near-Earth space is made, and penetration functions for typical spacecraft orbits are calculated.  相似文献   
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