Matra

About: Matra is a based out in . It is known for research contribution in the topics: Signal & Detector. The organization has 1330 authors who have published 1216 publications receiving 17967 citations.

Deicing device for a jet engine air inlet cowl

Abstract: Deicing device for the leading edge of the air inlet cowl of a jet engine. According to the invention, an injector (12) whose task is to inject pressurized hot air into the leading edge is connected to the pressurized hot air inlet by means of a ball joint (22).

Hyper-Viscoelastic Behavior of Healthy Abdominal Aorta

Abstract: The aim of the present study was to define biomechanical parameters of the healthy human abdominal aorta, usable to develop materials for the aortic phantom production. Such phantoms used in the training of endovascular treatment must describe the same morphology and mechanical behavior properties as the patient's aorta. To accurately identify these biomechanical parameters, ex vivo experiments in uniaxial tensile and dynamic simple shear tests were performed on six human healthy abdominal aortas (6 males, between 12 and 69 years old). A solid generalized Maxwell model including Yeoh expression for the elastic part was used to describe the hyper-viscoelastic behavior of the aorta. The results obtained from uniaxial tensile tests show an exponential-like increase in stiffness, which can be described by three hyperelastic parameters ( C 1 , C 2 and C 3 ). From dynamic shear experiments, the viscous part of the global biomechanical behavior was expressed in a specific angular-frequency range (1 to 315 rad/s). Three Maxwell elements ( β 1 , β 2 , and β 3 ) put on three constant times ( τ 1 = 0.003 s , τ 2 = 0.03 s , and τ 3 = 0.3 s ) respectively, were necessary to describe it. As this relatively high number of viscoelastic parameters may be difficult to control in the development of materials, we suggest defining the viscous behavior with the global viscosity η 0 that combines the viscoelastic contributions of each Maxwell element. In conclusion, four biomechanical parameters: C 1 , C 2 , C 3 and η 0 , must be considered for the development of materials used in the aortic phantom production.

Method of setting up communications in a packet switching system

Abstract: A call server, a media gateway (60) and terminals are connected to a packet switching network (54). Other terminals (32, 34) are connected to the gateway interfaces. The method for setting up communication comprises generating a call processing task for the calling terminal in the call server, transmitting by said task a connection set-up message including at least an identifier of the called terminal and a first network address enabling to reach the calling terminal, generating a call processing task for the called terminal, and sending, based on said task to a second network address enabling to reach the called terminal, signalling data indicating in particular the first network address. When the first and second network addresses are identical and correspond to a gateway address, the latter sets up between the two terminals a communication path which does not pass through the network.

Foam material body for a pad, particularly a mattress

Abstract: A foam material body for a bed, particularly a mattress, has a body part with a plurality of channels each having two deep channel portions located at opposite sides of a transverse plane of symmetry of the channel, and two narrow channel portions each extending from a respective one of the deep channel portions of the same channel. Each of the channels may have a maximum cross sectional dimension in direction parallel to supporting surfaces which is greater than a maximum cross sectional dimension of each of the deep channel portions in direction normal to the supporting surfaces. Each of the deep channel portions can increase in direction away from the middle channel portion of each channel, so that web-like sections formed between two channels of each pair extend toward the middle channel portion of the respective channel.

Root homomorphic deconvolution schemes for speech processing in car noise environments

Abstract: The authors propose the use of a Root homomorphic approach instead of the classical Log in order to improve cepstral representation in noise. Recognition tests demonstrate the robustness of the Root-based analysis for noisy speech processing. It is shown that Root cepstral coefficients permit a heuristic extension of noise subtraction techniques into the cepstral domain. Finally, the authors extend their work to LP (linear prediction)-based cepstral analysis and show that the Root approach gives equivalent results when comparing direct (LFCC) and LP-based (LPCC) analysis schemes. A unified model is proposed, and it is concluded that both classical LPCC and LFCC analyses are suboptimal solutions of the authors' more general scheme. >