Papers by Keyword: LPI

Abstract: Pacitan City, the capital of Pacitan Regency is located at the southern part of East Java Province. This area is facing directly to the earthquake source due to plates subduction between Indo-Australia and Eurasia plates. Southern part of this City is coastal resort area which is geologicaly consists of alluvial deposits that is still under compaction and some of the upper layers are consist of loose material. According to the condition, this area is vulnerable to the earthquake induced soil liquefaction. Five soil borings and 30 cone penetration tests were conducted in this study area to investigate soil properties for evaluating soil liquefaction. Severity of the potential surface damages due to liquefaction were identified by calculating Liquefaction Potential Index (LPI). The results show that study area is vulnerable to soil liquefaction, with potential damage severity vary from very low to very high. Medium to high severity of potential damage are distributed in almost area of the city, and only in the southern part close to the coast line have very high severity level.

Abstract: In order to enhance the capability of anti-jamming and Low Probability of Intercept (LPI) of radar system, spread spectrum signals are designed for modern radar system. Emission signal is coded with PN codes at the transmitting terminal. Spectrum of signal is spreaded and multi-signal mixed together, so it is not easy to intercept. At the receiving terminal, undesired signals are spreaded when dispreading desired signal. Signal to noise ratio (SNR) of the received signals is raised after despreading, so the detection range broadens. Computer simulations verify the good performance of the proposed approach.

Abstract: A pseudo-random phase-coded quasi-CW radar signal processor is designed，and implemented based on a parallel signal processing platform. Distance sidelobe and “echo eclipse” are two problems inherent to the phase-coded quasi-CW radar. In this paper, “Code agility” method is used to suppress the distance sidelobe, which has good performance even when the radar echo is badly eclipsed. Software of the radar signal processor is characterized by pipelined processing, and the DSP program is based on real-time operation system. Results of the field experiment verify the correctness of our design.

Abstract: Various technology programmes in Europe are concerned with preparing for future propulsion technologies to reduce the costs and increase the life time of components for liquid rocket engine components. One of the key roles to fulfil the future requirements and for realizing reusable and robust engine components is the use of modern and innovative materials. One of the key technologies which concern various engine manufacturers worldwide is the development of fibrereinforced ceramics – CMC's (Ceramic Matrix Composites). The advantages for the developers are obvious – the low specific weight, the high specific strength over a large temperature range, and their good damage tolerance compared to monolithic ceramics make this material class extremely interesting as a construction material. Different kind of composite materials are available and produced by EADS ST, the standard material SICARBON® (C/SiC made by Liquid Polymer Infiltration) and the new developed and qualified composite materials SICTEX® (C/SiC made by Liquid Silicon Infiltration) and CARBOTEX® (C/C made by Rapid Chemical Vapour Infiltration). The composites are based on textile techniques like weaving, braiding, stiching and sewing to produce multiaxial preforms, the SICTEX® material is densificated by the cost effective Liquid Silicon Infiltration (LSI). Over the past years, EADS Space Transportation (formerly DASA) has, together with various partners, worked intensively on developing components for airbreathing and liquid rocket engines. Since this, various prototype developments and hot firing-tests with nozzle extensions for upper and core stage engines and combustion chambers of satellite engines were conducted. MBDA France and EADS-ST have been working on the development of fuel-cooled composite structures like combustion chambers and nozzle extensions for future propulsion applications.