International Conference on Sustainable Rice Production - Policy, Technology and Extension Celebration Activity for International Year of Rice and World Food Day 2004

Rice is the staple food of more than half of the world’s Population.The production,processing and management of paddy rice have provided the basic conditions for the living of mankind.The production of rice has not only created

NEW METHOD FOR PAPR REDUCTION BASED ON UNION STRATEGY IN OFDM SYSTEM

Because of the high Peak to Average Power Ratio(PAPR) in Orthogonal Frequency Division Multiplexing(OFDM) system, a union algorithm for PAPR reduction, combined with modified Active Constellation Extension Smart Gradient-Project(ACE-SGP) algorithm and adaptive clipping algorithm, is proposed in this paper. First of all, an adaptive strategy is used to control the size of clipping level A. Secondly, a novel step factor m is adopted to complete iterative computations in order to increase the convergence speed greatly. Simulation results show that the modified algorithm has reduced the PAPR and improved the convergence speed significantly without side information and any processing at the receiver end.

Oceanic plate subduction history in the western Pacific Ocean:Constraint from late Mesozoic evolution of the Tan-Lu Fault Zone

The NE-to NNE-striking Tan-Lu Fault Zone(TLFZ) is the largest fault zone in East China, and a typical representative for the circum-Pacific tectonics. Its late Mesozoic evolution resulted from subduction of the Paleo-Pacific Plate,and can be used for indication to the subduction history. The TLFZ reactivated at the end of Middle Jurassic since its origination in Middle Triassic. This phase of sinistral motion can only be recognized along the eastern edge of the Dabie-Sulu orogenis,and indicates initiation of the Paleo-Pacific(Izanagi) Plate subduction beneath the East China continent. After the Late Jurassic standstill, the fault zone experienced intense sinistral faulting again at the beginning of Early Cretaceous under N-S compression that resulted from the NNW-ward, low-angle, high-speed subduction of the Izanagi Plate. It turned into normal faulting in the rest of Early Cretaceous, which was simultaneous with the peak destruction of the North China Craton caused by backarc extension that resulted from rollback of the subducting Izanagi Plate. The TLFZ was subjected to sinistral, transpressive displacement again at the end of Early Cretaceous. This shortening event led to termination of the North China Craton destruction. The fault zone suffered local normal faulting in Late Cretaceous due to the far-field, weak backarc extension. The late Mesozoic evolution of the TLFZ show repeated alternation between the transpressive strike-slip motion and normal faulting. Each of the sinistral faulting event took place in a relatively short period whereas every normal faulting event lasted in a longer period, which are related to the subduction way and history of the Paleo-Pacific Plates.