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731.
选取易武斗茶会为研究案例,以尺度转换为理论分析工具,通过参与式观察法和半结构化访谈法,深入分析易武斗茶会的发展历程并展示推动其发展演变的多元社会主体的不同行动与实践。研究发现:① 易武斗茶会的演变过程中存在2种尺度转换的方式,一种是为迎合普洱茶市场细分而进行的尺度下推,另一种是根据地方发展需求而进行的尺度上推。② 易武斗茶会尺度转换是在地方政府的推动、茶企的支持、茶农的配合以及茶客的偏好下共同驱动的。③ 多元主体的行动在推动易武斗茶会尺度转换的过程中满足了各自群体的利益诉求,地方依凭茶叶经济实现了本土发展。从节事的角度对中国茶文化进行深入分析研究,为茶村如何通过地方性节事活动实现本土发展提供理论依据与案例借鉴。 相似文献
732.
Use of the L2C signal for inversions of GPS radio occultation data in the neutral atmosphere 总被引:1,自引:0,他引:1
S. V. Sokolovskiy W. S. Schreiner Z. Zeng D. C. Hunt Y.-H. Kuo T. K. Meehan T. W. Stecheson A. J. Mannucci C. O. Ao 《GPS Solutions》2014,18(3):405-416
Results from processing FORMOSAT-3/COSMIC radio occultations (RO) with the new GPS L2C signal acquired both in phase locked loop (PLL) and open loop (OL) modes are presented. Analysis of L2P, L2C, and L1CA signals acquired in PLL mode shows that in the presence of strong ionospheric scintillation not only L2P tracking, but also L1CA tracking often fails, while L2C tracking is most stable. The use of L2C improves current RO processing in the neutral atmosphere mainly by increasing the number of processed occultations (due to significant reduction in the number of L2 tracking failures) and marginally by a reduction in noise in statistics. The latter is due to the combination of reduced L2C noise (compared to L2P) and increased L1CA noise in those occultations where L2P would have failed. This result suggests application of OL tracking for L1CA and L2C signals throughout an entire occultation to optimally acquire RO data. Two methods of concurrent processing of L1CA and L2C RO signals are considered. Based on testing of individual occultations, these methods allow: (1) reduction in uncertainty of bending angles retrieved by wave optics in the lower troposphere and (2) reduction in small-scale residual errors of the ionospheric correction in the stratosphere. 相似文献
733.
High-rate GPS measurements of earthquake-induced strong crustal movements reveal important information on large amplitude displacements, which cannot be obtained by other seismic monitoring equipment. However, obtaining accurate measurements of these strong movements can be challenging, because large magnitude earthquakes (M > 7) affect a wide area surrounding the epicenter. As a result, the GPS recorded movements are calculated with respect to distant sites (relative positioning), or with satellite parameters estimated from distant sites (precise point positioning). In order to improve the accuracy of the strong motion GPS measurements, we developed a new method, based on a spatial filtering technique. The method calculates the displacement of a high-rate monitoring network with respect to a moving near field site and uses a stacking technique to remove the movements of the reference site from all the time series. We applied the new method to the analysis of 5 Hz data acquired by the Nicoya Peninsula network, which recorded strong crustal movements induced by the 2012, M = 7.6 Costa Rica earthquake. The results were successfully tested with respect to 1 Hz time series calculated with a far field reference site. The spatial filtering method also removes other systematic common noise from the time series, possibly due to atmospheric delay or orbital errors and, hence, produces more accurate solutions that those based on far fields sites, or on near field site experiencing earthquake-induced action. 相似文献
734.
735.
Kuznetsov S. N. Bogomolov A. V. Denisov Yu. I. Kordylewski Z. Kudela K. Kurt V. G. Lisin D. V. Myagkova I. N. Podorol'skii A. N. Podosenova T. B. Svertilov S. I. Sylwester J. Stepanov A. I. Yushkov B. Yu. 《Solar System Research》2003,37(2):121-127
Based on X-ray, gamma-ray, and charged-particle measurements with several instruments onboard the Coronas-F satellite and on ACE and GOES experimental data presented on the Internet, we investigate the parameters of the solar flare of November 4, 2001, and the energetic-particle fluxes produced by it in circumterrestrial space. The increase in relativistic-electron fluxes for about 1.5 days points to a moving source (shock front). The structure of the energetic-particles fluxes in the second half of November 5, 2001, can be explained by the passage of the coronal mass ejection that was ejected on November 1, 2001, and that interacted with the shock wave from the flare of November 4, 2001. 相似文献
736.
E. P. Mazets S. V. Golenetskii V. N. Ilyinskii V. N. Panov R. L. Aptekar Yu. A. Guryan M. P. Proskura I. A. Sokolov Z. Ya. Sokolova T. V. Kharitonova A. V. Dyatchkov N. G. Khavenson 《Astrophysics and Space Science》1981,80(1):3-83
Data are presented on the temporal structure, fluxes, energy spectra and coordinates of the sources of gamma-ray bursts detected in the KONUS experiment on Venera 11 and Venera 12 space probes in the period September 1978 to May 1979. The statistical distributions of gamma bursts in duration, intensity, and peak power, as well as the distribution of the burst sources over the celestial sphere presented are based on the updated KONUS information obtained until February 1980. 相似文献
737.
738.
Eclipsing binary TX UMa was observed with the D.A.O. high-dispersion spectrographs in 1969–1970, with emphasis on the detailed coverage of the primary minimum. One spectrum was taken exclusively within totality, thus exhibiting an uncontaminated spectrum of the secondary component. This leads to spectral reclassification of the secondary (F6 IV). The narrowing of the line profile of the H-line in totality is interpreted in terms of synchronous rotation of the secondary (v sini80 km s–1) while the primary rotates faster (v sini130 km s–1) than synchronously (v sini50 km s–1). Although the secondary does not fill in its Roche lobe fully, the system exhibits pronounced indications of rather strong physical interaction. This is now supported also by the profound changes of the line profiles of the H-line with phase. 相似文献
739.
740.
A virtual multidimensional internal bond (VMIB) model developed to simulate the propagation of hydraulic fractures using the finite‐element method is formulated within the framework of the virtual internal bond theory (VIB) that considers a solid as randomized material particles in the micro scale, and derives the macro constitutive relation from the cohesive law between the material particles with an implicit fracture criterion. Hydraulic pressure is applied using a new scheme that enables simulation of hydraulically driven cracks. When the model is applied to study hydraulic fracture propagation in the presence of a natural fracture, the results show the method to be very effective. It shows that although the in situ stress ratio is the dominant factor governing the propagation direction, a natural fault can also strongly influence the hydraulic fracture behavior. This influence is conditioned by the shear stiffness of the fault and the distance to the original hydraulic fracture. The model results show that when the fault is strong in shear, its impact on hydraulic fracture trajectory is weak and the hydraulic fracture will likely penetrate the fault. For a weak fault, however, the fracture tends to be arrested at the natural fault. The distance between the fault and the hydraulic fracture is also important; the fault influence increases with decreasing distance. The VMIB does not require selection of a fracture criterion and remeshing when the fracture propagates. Therefore, it is advantageous for modeling fracture initiation and propagation in naturally fractured rock. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献