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There are lots of data communications among subtasks in big data processing, especially those key pair intermediate data. Its a key point concerning big data analytic area to process those intermediate data efficiently. However state of the art big data systems rare put an eye on the optimization and effeicient management of those intermediate data. On one hand, intermediate data in MapReduce and...
Adaptive beamforming algorithm performance decreases sharply with the increase of array errors. Beamforming algorithm based on diagonal loading is a simple and effective method for improving robustness. But it is difficult to determine the optimal diagonal loading factor, and the fixed load value does not change with the array error, reduce the loading effect. To solve the above problems, this paper...
Multi-channel amplitude and phase calibration is the premise and foundation to obtain the high quality pattern. On the issues of W-band radar calibration, a calibration approach based on space-fed transceiver is proposed. Based upon two-dimensional four subarrays single-polarized antenna model, rotate two-dimensional turntable in small angle continuously until the centers of two antennas at both sides...
The simulation algorithm based on the field of power electronics and motor control areas of application package software simulation (PSIM) for array of photovoltaic cells in a certain light maximum power point tracking (MPPT) had been built, different simulation step by analysis of the impact of MPPT. Simulation results show that: the model parameters of an array of photovoltaic cells correspond exactly...
The quasi-optics sub-system of Millimeter-wave focal plane arrays imaging system includes the design of system parameters, multi-beam design of focusing element and design of feed antenna. Design of focusing element decides the spatial resolution and the maximum field of view of the system. The design and arrangement of the feed antenna related to the overflow efficiency and the spatial sampling rate...
This paper introduces the background of the Session Initiation Protocol (SIP) and the functions of SIP server. For the servers' needs to fast search user information, two solutions with the introduction of HASH technology were proposed. They were Division Method and Two-Dimensional Array to construct HASH function. Comparing to their performances, the latter could make the server work more efficiently...
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