scholarly journals Evaluation of high-performance space nuclear electric generators for electric propulsion application

2002 ◽  
Author(s):  
Gordon Woodcock
Keyword(s):  
Electric Propulsion ◽  
High Performance ◽  
Performance Space ◽  
Electric Generators

scholarly journals Towards Continuous Production of Shaped Honeycombs

2018 ◽  
Author(s):  
Sam E. Calisch ◽  
Neil A. Gershenfeld
Keyword(s):  
High Performance ◽  
Continuous Production ◽  
Continuous Process ◽  
Three Dimensional ◽  
Sandwich Panels ◽  
Performance Space ◽  
Bending Loads ◽  
Future Work ◽  
The Impact ◽  
Parallel Folding

Honeycomb sandwich panels are widely used for high performance parts subject to bending loads, but their manufacturing costs remain high. In particular, for parts with non-flat, non-uniform geometry, honeycombs must be machined or thermoformed with great care and expense. The ability to produce shaped honeycombs would allow sandwich panels to replace monolithic parts in a number of high performance, space-constrained applications, while also providing new areas of research for structural optimization, distributed sensing and actuation, and on-site production of infrastructure. Previous work has shown methods of directly producing shaped honeycombs by cutting and folding flat sheets of material. This research extends these methods by demonstrating work towards a continuous process for the cutting and folding steps of this process. An algorithm for producing a manufacturable cut-and-fold pattern from a three-dimensional volume is designed, and a machine for automatically performing the required cutting and parallel folding is proposed and prototyped. The accuracy of the creases placed by this machine is characterized and the impact of creasing order is demonstrated. Finally, a prototype part is produced and future work is sketched towards full process automation.

Efficient Space-Time Two Dimensional RAKE Receiver in Asynchronous Cooperative Communications Systems with Full Diversity

2014 ◽  
Vol 536-537 ◽  
pp. 719-725
Author(s):  
Dong Wu Li ◽  
Chang Xing Pei ◽  
Yun Liang Meng
Keyword(s):  
Cooperative Communication ◽  
Communication System ◽  
Cooperative Communications ◽  
High Performance ◽  
Rake Receiver ◽  
Space Time ◽  
Two Dimensional ◽  
Combination Rules ◽  
Performance Space ◽  
Full Diversity

A high-performance space-time two dimensional RAKE receiving algorithm was proposed in asynchronous cooperative communication system. the transmitting signals were estimated coarsely by traditional space-time rake receiver, then on the basis of that we introduce feedback technology, each multipath signal of transmitted signals was composed by the decision results, and then every multipath component in the received signal can be obtained by eliminating the composed multipath signals from the received signal. Finally, the multipath components were combined by space-time combination and multipath combination rules accordingly, so spatial as well as multipath diversities were achieved. Simulation results show that the new scheme can reduce the bit error rate dramatically compare with traditional space-time RAKE in asynchronous cooperative communication system.

Main results of the DAMPE space detector after 4 years in orbit

2020 ◽  
Vol 35 (36) ◽  
pp. 2044024
Author(s):  
Piergiorgio Fusco
Keyword(s):  
Gamma Rays ◽  
High Performance ◽  
Angular Resolution ◽  
Dark Matter Particle ◽  
Electromagnetic Calorimeter ◽  
Performance Space ◽  
Scientific Institutions ◽  
Chinese Academy Of Sciences ◽  
And Performance ◽  
Academy Of Sciences

The DArk Matter Particle Explorer (DAMPE) is a high-performance space particle detector launched in orbit in 2015 by a collaboration of Chinese, Italian and Swiss scientific institutions, coordinated by the Chinese Academy of Sciences. It consists of a high-resolution segmented BGO electromagnetic calorimeter with a depth of 32 radiation lengths, a silicon-tungsten tracker-converter with an angular resolution below [Formula: see text], an anti-coincidence shield and ion detector, and a neutron detector. The detector characteristics and performance, and the latest observations of cosmic electrons up to 5 TeV, protons and nuclei up to 100 TeV and gamma-rays up to 10 TeV are presented.

scholarly journals Experimental Investigations of a Krypton Stationary Plasma Thruster

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
A. I. Bugrova ◽  
A. M. Bishaev ◽  
A. V. Desyatskov ◽  
M. V. Kozintseva ◽  
A. S. Lipatov ◽  
...  
Keyword(s):  
Electric Propulsion ◽  
High Performance ◽  
Specific Impulse ◽  
Field Configuration ◽  
Experimental Investigations ◽  
Hall Effect Thruster ◽  
Stationary Plasma ◽  
Anode Efficiency ◽  
Plasma Thruster ◽  
Stationary Plasma Thrusters

Stationary plasma thrusters are attractive electric propulsion systems for spacecrafts. The usual propellant is xenon. Among the other suggested propellants, krypton could be one of the best candidates. Most studies have been carried out with a Hall effect thruster previously designed for xenon. The ATON A-3 developed by MSTU MIREA (Moscow) initially defined for xenon has been optimized for krypton. The stable high-performance ATON A-3 operation in Kr has been achieved after optimization of its magnetic field configuration and its optimization in different parameters: length and width of the channel, buffer volume dimensions, mode of the cathode operation, and input parameters. For a voltage of 400 V and the anode mass flow rate of 2.5 mg/s the anode efficiency reaches 60% and the specific impulse reaches 2900 s under A-3 operating with Kr. The achieved performances under operation A-3 with Kr are presented and compared with performances obtained with Xe.

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