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Network Protocol Support in SDP
Published in Radhika Ranjan Roy, Handbook of SDP for Multimedia Session Negotiations, 2018
The use of <transport> values "AAL1/<corporateName>," "AAL2/<corporateName>," "AAL5/<corporateName>," "AAL1/IEEE:<oui>," "AAL2/IEEE:<oui>," and "AAL5/IEEE:<oui>" is similar. These indicate nonstandard transport mechanisms or AAL2 profiles, which should be used consistently within the scope of an application or deployment. The parameter <corporateName> is the registered, globally unique name of a corporation (e.g., Cisco, Telcordia, etc.). The parameter <oui> is the hex representation of a three-octet field identical to the Organizationally Unique Identifier (OUI) maintained by the Institute of Electrical and Electronics Engineers (IEEE). Since this is always represented in hex, the "0x" prefix shall not be used. Leading zeros can be omitted. For example, "IEEE:00000C" and "IEEE:C" both refer to Cisco Systems, Inc.
Optimal Corner Frequency in High-Pass Filtering of Strong Ground Motions and Its Effect on Seismic Intensity
Published in Journal of Earthquake Engineering, 2021
Mohammad Reza Falamarz-Sheikhabadi, A. Zerva
in which , and indicate processed acceleration, velocity and displacement with the HPCF along the q-th direction, respectively, ti (i = 1, 2, 3, …, N) indicates discrete time with tN being the duration of the unprocessed simulated acceleration time series, and ∆t is the time step. In Eqs. (2.a)–(2.c), ∆ωc indicates the breadth of frequencies that are filtered between two consecutive corner frequencies. ∆ωc should be considered small enough to appropriately capture the variations in the mean-square differences of the time series between consecutive corner frequencies. The practical range of ∆ωc for the evaluation of the optimal HPCF corresponding to an earthquake record is presented in Section 3.5. In Eqs. (2.a)–(2.c), are time shifts to account for the zero-padding of the acceleration time series in the acausal processing operation. The shifting of the time series for the evaluation of the mean-square difference functions (MSDFs) is necessary, as utilizing the actual time of the processed accelerations, velocities and displacements in Eqs. (2.a)–(2.c) would be meaningless. In this process, each processed acceleration time series is aligned with respect to the original time series, or, alternatively, the leading zero-pads are removed, and then the processed time series is truncated to the duration of the original one, i.e. the trailing zero-pads are also removed. The identified from the acceleration time series is then utilized in the evaluation of the MSDFs of Eqs. (2.a)–(2.c). Clearly, this process facilitates the correct evaluation of the MSDFs, as now the processed accelerations, velocities and displacements have a common origin and a common duration. However, it should be emphasized at this point that the truncation of the zero-padding is used herein only for the evaluation of the MSDFs. As indicated before, truncation of the zero-padding cannot be conducted when the time series are utilized as input motions at the supports of structures, as this truncation will eliminate the benefits of the processing operation.