CREAM: 70 days of flight from 2 launches in Antarctica

The Cosmic-Ray Energetics And Mass balloon-borne experiment has been launched twice in Antarctica, first in December 2004 and again in December 2005. It circumnavigated the South Pole three times during the first flight, which set a flight duration record of 42 days. A cumulative duration of 70 days within 13 months was achieved when the second flight completed 28 days during two circumnavigations of the Pole on 13 January 2006. Both the science instrument and support systems functioned extremely well, and a total 117 GB of data including 67 million science events were collected during these two flights. Preliminary analysis indicates that the data extend well above 100 TeV and follow reasonable power laws. The payload recovered from the first flight has been refurbished for the third flight in 2007, whereas the payload from the second flight is being refurbished to be ready for the fourth flight in 2008. Each flight will extend the reach of precise cosmic-ray composition measurements to energies not previously possible.     

Analysis of dynamics of a passive line-of-sight stabilization system with four-axis gimbal suspension

A mechanical model of the line-of-sight stabilization system for the optical device mounted on a movable carrier vehicle is considered. The nonlinear Lagrange equations of motion for a four-axis gimbal suspension are derived. Requirements on design and parameters for the passive line-of-sight shock absorption system of the optoelectronic payload are worked out.     

A parallel computer architecture for continuous simulation

A parallel computer specifically designed for the solution of ordinary differential equations is described. The first version of the machine contains thirty-two processors, running in an asynchronous multiple-instruction/multiple-data mode, communicating with high-speed parallel busses. Synchronization is accomplished by a microprogrammable communication controller. A number of processors have been designed and built for the machine. The processor types offer a wide variation in solution speed and accuracy. To permit easy comparisons with analog and hybrid systems, performance is measured by finding the highest frequency sine wave which can be integrated in real time with an accuracy of 0.1% or higher. Using this performance measure the performance limit of the current machine is 2000 Hz. The structure is capable of solving systems described by differential equations up to order sixty-four at these performance limits     

Magnetically inflatable SPS with energy storage capability

A new approach to superconductive magnetic energy storage (SMES) for solar power satellite (SPS) with inherent rigidity is introduced in this paper. The rigidity of this SMES originating from the electromagnetic forces within it, can eliminate the need for mechanical building blocks for support structure. This force can also be used for the deployment of the system in space. In addition, the storage capability of the system allows its use in low Earth orbit (LEO) which reduces the launching and transmission costs. The paper also discusses the basic design and the operation of the proposed SPS system     

Investigations on-board the biosatellite Cosmos-83.

The program of the 5 day flight of the biosatellite Cosmos-1514 (December 1983) envisaged experimental investigations the purpose of which was to ascertain the effect of short-term microgravity on the physiology, growth and development of various animal and plant species. The study of Rhesus-monkeys has shown in that they are an adequate model for exploring the mechanisms of physiological adaptation to weightlessness of the vestibular apparatus and the cardiovascular system. The rat experiment has demonstrated that mammalian embryos, at least during the last term of pregnancy, can develop in microgravity. This finding has been confirmed by fish studies. The experiment on germinating seeds and adult plants has given evidence that microgravity produces no effect on the metabolism of seedlings and on the flowering stage.     

Gravity-dependent reactions of the moss Pohlia nutans protonemata.

In darkness, protonemata of Pohlia nutans (Hedw.) grew negatively gravitropically (upwards). However, not all filaments became gravitropic immediately after transfer to darkness. Some of them (~20%) for several days grew in different directions with respect to gravity. The apical cells of those protonemata predominantly contained multiple chloroplasts. The intensity of chlorophyll fluorescence rapidly decreased in the apical cells of such protonemata while starch content increased in comparison with upright growing protonemata. Light, especially in the red and blue part of the spectrum, inhibited protonemal gravitropism. Red light induced stronger inhibitory effects than blue light. Red light of 1.0 to 1.5 micromoles m-2 s-1 intensity induced bud differentiation in apical cells on almost all side branches of main protonemal filaments. Bright fluorescence of F-actin bundles in the tip of apical protonematal cells and a delicately fluorescing network enclosing plastids basal to the tip in a sedimentation zone were visualized. Bright fluorescence of actin as local patches and fine prominent axially oriented bundles was observed in cells of gametophore buds.     

Working group 1: Small scale features

A review is given of the activities of the working group on small scale features at the 2nd SOHO Workshop on Elba, 27 September–1 October 1993. The small scale and filamentary structure of the solar transition region, and possibly also the corona, was pointed out. The reported observations furthermore demonstrated that the upper solar atmosphere is strongly dynamical, containing rapidly flowing gas and with features changing with time. Theoretical concepts and simulations of conditions in the transition region and corona were presented and discussed. Finally some ideas on future observations and modelling were put forward.     

Enhancement of VLF-ducts under the action of high power radio wave on the ionospheric F-region

Wave effects are discussed pointing to improvement of whistler propagation in the ionosphere illuminated by a powerful radio wave. The large scale irregularities (ducts) responsible for these effects are formed in the illuminated ionospheric region by the process of electron heating by the fields of the pump wave and excited plasma oscillations. These irregularities may also be created in the ionosphere and plasmasphere by fluxes of suprathermal electrons accelerated by the plasma turbulence in the reflection region of the pump wave.     

DOA estimation using one-bit quantized measurements

The effects 1-bit quantization of the input samples has on the direction-of-arrival (DOA) estimation accuracy are considered. The signal model assumes a single stochastic Gaussian point source that is embedded in white Gaussian noise (WGN). The inherent limitations governed by the extreme clipping of the input data are analyzed using the Cramer-Rao bound (CRB) that is derived for a two-sensor array. In addition, several estimators for the I-bit estimation are discussed. Numerical and analytical analyses of the estimation error reveal weak dependency on signal-to-noise ratio (SNR) with singular behavior of the estimation error in certain DOA angles.