In the paper, source mechanisms of 33 small-moderate earthquakes occurred in Yunnan are determined by modeling of regional waveforms from Yunnan digital seismic network. The result shows that most earthquakes occurred...In the paper, source mechanisms of 33 small-moderate earthquakes occurred in Yunnan are determined by modeling of regional waveforms from Yunnan digital seismic network. The result shows that most earthquakes occurred within or near the Chuandian rhombic block have strike-slip mechanism. The orientations of maximum compressive stresses obtained from source mechanism are changed from NNW-SSN to NS in the areas from north to south of the block, and tensile stresses are mainly in ENE-WSW or NE-SE. In the eastern Tibetan Plateau, the orientations of maximum compressive stress radiate toward outside from the plateau, and the tensile stress orientations mostly parallel to arc structures. Near 28N the orientations of both maximum compressive stress and tensile stress changed greatly, and the boundary seems to correspond to the southwestern extended line of Longmenshan fault. Outside of the Chuandian rhombic block, the orientations of P and T axes are some different from those within the block. The comparison shows that the source mechanism of small-moderate events presented in the paper is consistence with that of moderate-strong earthquakes determined by Harvard University, which means the source mechanism of small-moderate events can be used to study the tectonic stress field in this region.展开更多
Two new compounds, oleanolic acid 28-O--D-glucopyranosyl-3-O--L-arabinopyrano- syl-(13)-(6-butyl ester)--D-glucuropyranoside 1, oleanolic acid 28-O--D-glucopyranosyl- (16)--D-glucopyranoside 2 have been isolated from ...Two new compounds, oleanolic acid 28-O--D-glucopyranosyl-3-O--L-arabinopyrano- syl-(13)-(6-butyl ester)--D-glucuropyranoside 1, oleanolic acid 28-O--D-glucopyranosyl- (16)--D-glucopyranoside 2 have been isolated from the roots of Hemsleya penxianensis var. gulinensis. Their structures were determined on the bases of the spectral and chemical evidences.展开更多
A memory and driving clock efficient design scheme to achieve WCDMA high-speed channel decoder on a single XILINX’ XVC1000E FPGA chip is presented. Using a modified MAP algorithm, say parallel Sliding Window logarith...A memory and driving clock efficient design scheme to achieve WCDMA high-speed channel decoder on a single XILINX’ XVC1000E FPGA chip is presented. Using a modified MAP algorithm, say parallel Sliding Window logarithmic Maximum A Posterior (PSW-log-MAP), the on-chip turbo decoder can decode an information bit by only an average of two clocks per iteration. On the other hand, a high-parallel pipeline Viterbi algorithm is adopted to realize the 256-state convolutional code decoding. The final decoder with an 8×chip-clock (30 72MHz) driving can concurrently process a data rate up to 2 5Mbps of turbo coded sequences and a data rate over 400kbps of convolutional codes. There is no extern memory needed. Test results show that the decoding performance is only 0 2~0 3dB or less lost comparing to float simulation.展开更多
基金The National Key Basic Research Program under the Project "Mechanism and Prediction of Continental Strong Earthquake"(G1998040700) and Joint Seismological Science Foundation of China (100108).
文摘In the paper, source mechanisms of 33 small-moderate earthquakes occurred in Yunnan are determined by modeling of regional waveforms from Yunnan digital seismic network. The result shows that most earthquakes occurred within or near the Chuandian rhombic block have strike-slip mechanism. The orientations of maximum compressive stresses obtained from source mechanism are changed from NNW-SSN to NS in the areas from north to south of the block, and tensile stresses are mainly in ENE-WSW or NE-SE. In the eastern Tibetan Plateau, the orientations of maximum compressive stress radiate toward outside from the plateau, and the tensile stress orientations mostly parallel to arc structures. Near 28N the orientations of both maximum compressive stress and tensile stress changed greatly, and the boundary seems to correspond to the southwestern extended line of Longmenshan fault. Outside of the Chuandian rhombic block, the orientations of P and T axes are some different from those within the block. The comparison shows that the source mechanism of small-moderate events presented in the paper is consistence with that of moderate-strong earthquakes determined by Harvard University, which means the source mechanism of small-moderate events can be used to study the tectonic stress field in this region.
基金We are grateful to State Key Project of Foundational Research of China (G1998061308) and the National Natural Science Foundation of China (G200071004) for support of this research.
基金supported by Natural Science Foundation of Yunnan and National Natural Science Foundation of China (Grant No.98C089M and No.39970086). The authors were grateful to the Departmental of Instrument Analysis Kunming Institute of Botany Chinese Academy o
文摘Two new compounds, oleanolic acid 28-O--D-glucopyranosyl-3-O--L-arabinopyrano- syl-(13)-(6-butyl ester)--D-glucuropyranoside 1, oleanolic acid 28-O--D-glucopyranosyl- (16)--D-glucopyranoside 2 have been isolated from the roots of Hemsleya penxianensis var. gulinensis. Their structures were determined on the bases of the spectral and chemical evidences.
文摘A memory and driving clock efficient design scheme to achieve WCDMA high-speed channel decoder on a single XILINX’ XVC1000E FPGA chip is presented. Using a modified MAP algorithm, say parallel Sliding Window logarithmic Maximum A Posterior (PSW-log-MAP), the on-chip turbo decoder can decode an information bit by only an average of two clocks per iteration. On the other hand, a high-parallel pipeline Viterbi algorithm is adopted to realize the 256-state convolutional code decoding. The final decoder with an 8×chip-clock (30 72MHz) driving can concurrently process a data rate up to 2 5Mbps of turbo coded sequences and a data rate over 400kbps of convolutional codes. There is no extern memory needed. Test results show that the decoding performance is only 0 2~0 3dB or less lost comparing to float simulation.