Abstract: This study explores the possibility of a space station that will occupy a geostationary equatorial orbit (GEO) and create artificial gravity using centripetal acceleration. The concept of the station is to create a habitable, safe environment that can increase the possibility of space tourism by reducing the wide variation of hazards associated with space exploration. The ability to control the intensity of artificial gravity through Hall-effect thrusters will allow experiments to be carried out at different levels of artificial gravity. A feasible prototype model was built to convey the concept and to enable cost estimation. The SpaceX Falcon Heavy rocket with a 26,700 kg payload to GEO was selected to take the 675 tonne spacecraft into orbit; space station construction will require up to 30 launches, this would be reduced to 5 launches when the SpaceX BFR becomes available. The estimated total cost of implementing the Sussex Biocompatible International Space Station (BISS) is approximately $47.039 billion, which is very attractive when compared to the cost of the International Space Station, which cost $150 billion.
Abstract: Internet infrastructures in most places of the world
have been supported by the advancement of optical fiber technology,
most notably wavelength division multiplexing (WDM) system.
Optical technology by means of WDM system has revolutionized
long distance data transport and has resulted in high data capacity,
cost reductions, extremely low bit error rate, and operational
simplification of the overall Internet infrastructure. This paper
analyses and compares the system impairments, which occur at data
transmission rates of 2.5Gb/s and 10 Gb/s per wavelength channel in
our proposed optical WDM system for Internet infrastructure in
Tanzania. The results show that the data transmission rate of 2.5 Gb/s
has minimum system impairments compared with a rate of 10 Gb/s
per wavelength channel, and achieves a sufficient system
performance to provide a good Internet access service.
Abstract: Preprocessing of speech signals is considered a crucial step in the development of a robust and efficient speech or speaker recognition system. In this paper, we present some popular statistical outlier-detection based strategies to segregate the silence/unvoiced part of the speech signal from the voiced portion. The proposed methods are based on the utilization of the 3 σ edit rule, and the Hampel Identifier which are compared with the conventional techniques: (i) short-time energy (STE) based methods, and (ii) distribution based methods. The results obtained after applying the proposed strategies on some test voice signals are encouraging.