3S集成技术在城镇土地利用变更调查中的应用研究     

李钢  唐国金  付丽莉  马瑞尧  周玉宏  卢刚 《国土资源信息化》2007,(1):26-29

城镇地区由于建筑物密集、土地利用类型变化快、土地利用现状图比例尺较大等特点,土地利用变更调查主要依靠专业部门利用全站仪完成,但全站仪需要通视的特点限制了其工作效率。而采用3S集成技术进行城镇地区土地利用变更调查的技术方法,则可以相应提高工作效率。基于3S集成技术城镇地区土地利用变更调查的应用模式为:通过GPS接收机与笔记本电脑(已配置GIS软件系统)通讯,实现GPS与GIS的集成,并调用RS影像作为底图,既可实现实时的数据采集、存储和编辑。对于城镇地区部分GPS信号弱的地区,采用测边交会的方法则可以完成这些点的数据采集,克服了GPS使用盲区的限制。  相似文献   

基于NB-IoT技术的地震预警信息发布终端设备研制     

孙路强  高也  马超群  马胜 《震灾防御技术》2020,15(4):821-827

天津市地震局于2015年通过首都圈预警示范工程项目建设，完成地震预警信息服务网络建设，并选取6所学校安装地震预警信息发布装置，提供地震预警信息示范服务，但由于信息发布装置安装复杂且价格偏高，在一定程度上影响终端设备的普及，制约地震预警信息社会化服务进程。同时，已有终端设备如同黑箱，不利于二次开发应用，存在安全隐患，影响服务质量。因此，天津市地震局积极推进基于NB-IoT技术的地震预警信息发布终端设备研制，实现低成本、低功耗、低延时目标及地震预警信息社会化服务。  相似文献   

Thermochronology and exhumation rates of granitic intrusions at Mesa Central,Mexico     

Angel F. Nieto-Samaniego  María de Jesús Paulina Olmos-Moya  Gilles Levresse  Susana A. Alaniz-Alvarez  Fanis Abdullin  Alexis del Pilar-Martínez 《International Geology Review》2020,62(3):311-319

ABSTRACT

The Mesa Central of Mexico (MC) is an elevated plateau located 2000 m above sea level in central Mexico, where intrusions outcrop that register the history of exhumation-erosion occurring during the Late Cretaceous-Paleogene. The tectonic history of the region records formation of the Late Cretaceous-Paleogene ‘Mexican orogen’; this was followed by extension of the entire region and several plutons were then exhumed. The age and magnitude of the crustal uplift and erosion occurring during exhumation has not been addressed to date. Therefore, this study reports the crystallization and cooling ages of two plutons, the Tesorera Granodiorite and the Comanja Granite, and estimates their emplacement depths. Based on these data, the exhumation age of the Tesorera Granodiorite is estimated to be between ~73 Ma and ~63 Ma at an exhumation rate of ~528 m/m. y. and that of the Comanja Granite is 52 Ma and 48 Ma at an exhumation rate of ~2500 m/m. y. Exhumation-erosion event of the Tesorera Granodiorite was located on the trace of the San Luis-Tepehuanes Fault System and that of the Comanja Granite on the a trace of the El Bajío Fault System. Furthermore, the high exhumation rate in the Comanja Granite suggests that gravitational collapse played an important role during exhumation.  相似文献   

Diffusive-Shock-Accelerated Interplanetary Ions At Several Energies During the Solar Cycle 21 Maximum     

Rodríguez-Pacheco  J.  Sequeiros  J.  Del Peral  L.  Bronchalo  E.  Cid  C. 《Solar physics》1998,181(1):185-200

The most intense energetic particle (mainly proton) events in the energy range 36–1600 keV, during the years of maximum activity of solar cycle 21 (1978 to 1982), have been studied with regard to their spectra, temporal profiles, source location at the Sun, interplanetary plasma parameters and interplanetary magnetic field topology. In all the events, the particles were accelerated by the 'Diffusive Shock' acceleration mechanism, because all the events were 'long-duration events', shock-associated, and their spectra fitted to a power-law energetic particle spectrum dJ/dE E^-\gamma with the exponent values ranging from 1.25 up to 1.94, with a mean value of 1.60 ± 0.06. We also show that the spectral indexes are related to the shock properties by a linear expression. The solar sources were located on a wide longitudinal belt extending from 50^ W up to 73^ E. Neither the spectral indexes nor the shock parameters present any dependence on the source location at the Sun. Finally, only one event showed the complete set of properties that characterize the presence of a magnetic cloud associated with the event.  相似文献   

Images of Gradual Millimeter Emission and Multi-Wavelength Observations of the 17 august 1994 Solar Flare     

Silva  Adriana V.R.  Lin  R.P.  de Pater  Imke  White  Stephen M.  Shibasaki  K.  Nakajima  H. 《Solar physics》1998,183(2):389-405

We present a comprehensive analysis of the 17 August 1994 flare, the first flare imaged at millimeter (86 GHz) wavelengths. The temporal evolution of this flare displays a prominent impulsive peak shortly after 01:02 UT, observed in hard X-rays and at microwave frequencies, followed by a gradual decay phase. The gradual phase was also detected at 86 GHz. Soft X-ray images show a compact emitting region (20), which is resolved into two sources: a footpoint and a loop top source. Nonthermal emissions at microwave and hard X-ray wavelengths are analyzed and the accelerated electron spectrum is calculated. This energy spectrum derived from the microwave and hard X-ray observations suggests that these emissions were created by the same electron population. The millimeter emission during the gradual phase is thermal bremsstrahlung originating mostly from the top of the flaring loop. The soft X-rays and the millimeter flux density from the footpoint source are only consistent with the presence of a multi-temperature plasma at the footpoint.  相似文献   

A current ribbon model for energy storage and release with application to the flare of 7 January 1992     

Longcope  D. W.  Silva  A. V. R. 《Solar physics》1998,179(2):349-377

Observations of the flare on 7 January 1992 are interpreted using a topological model of the magnetic field. The model, developed here, applies a theory of three-dimensional reconnection to the inferred magnetic field configuration for 7 January. In the model field a new bipole ( 10²¹ Mx) emerges amidst pre-existing active region flux. This emergence gives rise to two current ribbons along the boundaries (separators) separating the distinct, new and old, flux systems. Sudden reconnection across these boundary curves transfers 3 ×10²⁰ Mx of flux from the bipole into the surrounding flux. The model also predicts the simultaneous (sympathetic) flaring of the two current ribbons. This explains the complex two-loop structure noted in previous observations of this flare. We subject the model predictions to comparisons with observations of the flare. The locations of current ribbons in the model correspond closely with those of observed soft X-ray loops. In addition the footpoints and apexes of the ribbons correspond with observed sources of microwave and hard X-ray emission. The magnitude of energy stored by the current ribbons compares favorably to the inferred energy content of accelerated electrons in the flare.  相似文献   

Regularity and estimation of methane emission from marshland in the Sanjiang Plain     

崔保山  马学慧  张明祥 《中国地理科学(英文版)》1998,8(1):74-84

ＲＥＧＵＬＡＲＩＴＹＡＮＤＥＳＴＩＭＡＴＩＯＮＯＦＭＥＴＨＡＮＥＥＭＩＳＳＩＯＮＦＲＯＭＭＡＲＳＨＬＡＮＤＩＮＴＨＥＳＡＮＪＩＡＮＧＰＬＡＩＮ①ＣｕｉＢａｏｓｈａｎ（崔保山）ＭａＸｕｅｈｕｉ（马学慧）ＣｈａｎｇｃｈｕｎＩｎｓｔｉｔｕｔｅｏｆＧｅｏｇｒ...  相似文献   

秦岭北坡旅游资源开发利用初探     

马占元 《地域研究与开发》1998,17(4):82-85

秦岭北坡是陕西省乃至全国旅游资源密集带之一。但由于开发和管理中存在诸多问题,近年来发展比较缓慢。在综合分析其开发优势和存在问题的基础上,提出了要全面规划,合理开发,走可持续发展之路,实现经济效益,社会效益和生态效益的协调统一。  相似文献   

山区资源开发的互补转换理论   总被引：2，自引：2，他引：0  

张爱国  张贵祥  马志正 《山地学报》1998,(2)

通过从结构与功能上对山区资源进行重新分类及相对优劣势分析,提出了合理开发山区资源的“山区资源开发互补转换理论”.  相似文献   

用附有条件的参数平差法求解秩亏网新探   总被引：3，自引：0，他引：3  

王仲锋  马正中 《测绘工程》1998,(2)

通过引进典则参数,以较简捷的方式证明了秩亏网平差应满足的条件方程,从而用附有条件的平差方法求解秩亏网平差参数的最小二乘极小范数解。  相似文献