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2019-01-16
Kimmich, J. M., Schlesinger, A., Tschaikner, M., Ochmann, M., Frank, S..  2018.  Acoustical Analysis of Coupled Rooms Applied to the Deutsche Oper Berlin. 2018 Joint Conference - Acoustics. :1–9.
The aim of the project SIMOPERA is to simulate and optimize the acoustics in large and complex rooms, with special focus on the Deutsche Oper Berlin as an example of application. Firstly, characteristic subspaces of the opera are considered such as the orchestra pit, the stage and the auditorium. Special attention is paid to the orchestra pit, where high sound pressure levels can occur, leading to noise related risks for the musicians. However, lowering the sound pressure level in the orchestra pit should not violate other objectives as the propagation of sound into the auditorium, the balance between the stage performers and the orchestra across the hall, and the mutual audibility between performers and orchestra members. For that reason, a hybrid simulation method consisting of the wave-based Finite Element Method (FEM) and the Boundary Element Method (BEM) for low frequencies and geometrical methods like the mirror source method and ray tracing for higher frequencies is developed in order to determine the relevant room acoustic quantities such as impulse response functions, reverberation time, clarity, center time etc. Measurements in the opera will continuously accompany the numerical calculations. Finally, selected constructive means for reducing the sound level in the orchestra pit will be analyzed.
2015-05-04
Yuying Wang, Xingshe Zhou.  2014.  Spatio-temporal semantic enhancements for event model of cyber-physical systems. Signal Processing, Communications and Computing (ICSPCC), 2014 IEEE International Conference on. :813-818.

The newly emerging cyber-physical systems (CPS) discover events from multiple, distributed sources with multiple levels of detail and heterogeneous data format, which may not be compare and integrate, and turn to hardly combined determination for action. While existing efforts have mainly focused on investigating a uniform CPS event representation with spatio-temporal attributes, in this paper we propose a new event model with two-layer structure, Basic Event Model (BEM) and Extended Information Set (EIS). A BEM could be extended with EIS by semantic adaptor for spatio-temporal and other attribution enhancement. In particular, we define the event process functions, like event attribution extraction and composition determination, for CPS action trigger exploit the Complex Event Process (CEP) engine Esper. Examples show that such event model provides several advantages in terms of extensibility, flexibility and heterogeneous support, and lay the foundations of event-based system design in CPS.