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101.
选取我国沿岸18个海洋观测站,对SBF3-1、SBF3-2、LPB1-2、SZF型自动测波仪器与目测、岸用测波仪两种非自动测波方式的海浪观测参数进行了比较分析。研究发现,与非自动测波方式相比,SBF3-1型浮标观测波高无明显变化,观测周期具有显著变大的特点;SBF3-2型浮标观测波高多数情况下具有变小的特点,观测周期保持不变或趋于变大;LPB1-2型声学测波仪观测波高有微弱变大的特点,观测周期无明显变化或微弱变大;SZF型浮标观测波高和观测周期既存在明显变大的情况,也存在明显变小或变化不明显的情况,无明显共性观测特点。 相似文献
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As a result of our ability to acquire large volumes of real-time earthquake observation data, coupled with increased computer performance, near real-time seismic instrument intensity can be obtained by using ground motion data observed by instruments and by using the appropriate spatial interpolation methods. By combining vulnerability study results from earthquake disaster research with earthquake disaster assessment models, we can estimate the losses caused by devastating earthquakes, in an attempt to provide more reliable information for earthquake emergency response and decision support. This paper analyzes the latest progress on the methods of rapid earthquake loss estimation at home and abroad. A new method involving seismic instrument intensity rapid reporting to estimate earthquake loss is proposed and the relevant software is developed. Finally, a case study using the M L4.9 earthquake that occurred in Shun-chang county, Fujian Province on March 13, 2007 is given as an example of the proposed method. 相似文献
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105.
将INTEX-B排放源应用到空气质量模型Model3-CMAQ中,对中国地区对流层NO2的浓度分布进行了数值模拟,并与OMI卫星对流层NO2资料进行了对比和验证。结果表明:将INTEX-B排放源应用到Model3-CMAQ模式,模拟的NO2浓度在中国地区的分布、季节变化规律与卫星资料所得结果一致。敏感性试验表明,工业及电厂排放对NO2的浓度贡献最大,而交通排放的贡献相对较小,两种排放均主要集中在京津、长江三角洲等经济发达地区。 相似文献
106.
Spatial variation of acceleration response spectra is examined using strong motion records for a large number of events from dense accelerometer arrays at Chiba in Japan and SMART-1 in Lotung, Taiwan. The effects of earthquake component, structural damping, earthquake magnitude, focal depth, epicentral distance, structural time period, and station separation on the intra-event variation of response spectra are examined first through an empirical analysis and then through a least-square regression fit for parametric study. A very large scatter of the response spectra ratio is observed for both arrays, especially for SMART-1 array. The mean values of the ratio vary from 10 to 20 per cent for Chiba array while they vary from 25 to 50 per cent for SMART-1 array. The coefficients of variation of the ratio range from 5 to 25 per cent for Chiba array and 30 to 50 per cent for SMART-1 array. The correlation among response spectra is found to be inversely proportional to station separation and shows frequency dependence. For larger time periods, the correlation is lower and not higher. The correlation is also lower for UD earthquake component as compared to the two horizontal components. For higher damping ratio, the correlation among spectra is higher. The effect of the earthquake magnitude, focal depth and epicentral distance on the spatial variation is complex. The three parameters having implicit interdependence, considering their combined effect, a positive contribution to the value of ratio of response spectra is observed in the case of larger earthquake events. Furthermore, as mentioned above, the spatial variation for SMART-1 array is much larger than that for Chiba array. This difference can be attributed mainly to the difference in distance between the instruments in the two arrays. However, some of the difference is considered to be due to site specific characteristics. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
107.
海洋站业务化观测仪器是业务化海洋观测系统的重要实体支撑。将我国海洋站中典型的国产业务化测量仪器与美国同类仪器在性能指标方面进行了对比分析,结合世界前沿海洋仪器发展现状总结了未来主要发展趋势,探讨了我国业务化海洋仪器优先发展的主要方向。结果表明,相比美国,我国国产验潮仪精度低1个数量级,测波仪的波高、周期和波向精度分别平均低0.2 m、0.27 s和5°~10°,国产观测仪器在业务运行可靠性和稳定性方面存在不足。世界海洋观测装备将更加信息化、智能化、专业化和模块化,并通过谱系化发展使其功能日臻完善,可靠性不断提高。在此趋势下,我国业务化海洋观测仪器应优先重点发展高精度传感原件和材料、抗生物污损和防腐蚀技术以及智能电子电路、人工智能和自动化技术等。 相似文献
108.
页岩气、致密油气、深井超深井油气和深水油气的勘探开发对钻井工具与仪器提出了更高要求。本文介绍了国外钻井工具与仪器的新进展,钻井工具包括高效破岩钻头(Aegis铠装合金钻头、Crush&Shear?混合式钻头、智能自适应钻头、StrataBlade*凹面金刚石元件钻头和HyperBlade*双曲面金刚石元件钻头)、辅助破岩工具(Navi-Drill DuraMax井下马达、NitroForce?高性能螺杆和耐温300 ℃螺杆钻具)和循环短节(iCWD智能循环短节、iDisc智能循环和丢手工具、MOCS G2循环短节和JetStream?RFID循环短节),而钻井仪器包括旋转导向工具(Lucida高端旋转导向系统、RST旋转导向系统、VectorEDGE旋转导向系统、HALO高性能旋转导向系统和NeoSteer@bit导向系统)和随钻测量仪器(TruLink*高分辨率动态MWD、IriSphere*随钻前视LWD、HEX200℃高温LWD和QuestTM随钻陀螺测斜仪)。在此基础上,对国内钻井工具与仪器的未来发展提出了建议。最后指出我国应尽快完成核心钻井工具与仪器的国产化,继续加大低成本替代技术的研究力度,以实现经济有效开发。 相似文献
109.
Detection of nitric acid (HNO<Subscript>3</Subscript>) in the atmosphere using the LOPAP technique 总被引:1,自引:0,他引:1
Jörg Kleffmann Traian Gavriloaiei Yasin Elshorbany Milagros Ródenas Peter Wiesen 《Journal of Atmospheric Chemistry》2007,58(2):131-149
A new instrument (LOPAP: LOng Path liquid Absorption Photometer) for the sensitive detection of nitric acid (HNO3) in the atmosphere is described. HNO3 is sampled in a temperature controlled stripping coil mounted in an external sampling module to minimize sampling artefacts in sampling lines. After conversion into a strongly absorbing dye, HNO3 is detected in long path absorption in special Teflon® AF 2400 tubes used as liquid core wave guides. For the correction of some interferences, due to for example HONO and particle nitrate, two channels are used in series. The interferences from several potential interfering compounds including particle nitrate were quantified in the laboratory and in a large outdoor simulation chamber. With the exception of the interference caused by N2O5, which is quantitatively measured by the instrument, all tested interferences can be corrected under atmospheric conditions. Thus, in the instrument only the sum of N(V) from HNO3 and N2O5 is determined, which is expected to be a common problem of wet chemical HNO3 instruments. The instrument has a detection limit of 5–30 pptv for a time response of 6–2 min, respectively and was validated against the FTIR technique in a large outdoor simulation chamber. In addition, the applicability of the instrument was demonstrated in a field campaign. 相似文献
110.
介绍了国内外第一台矿物热敏参数测试仪研制的原理、应用范围和对一些金属矿物、半导体矿物的测试情况以及仪器在浙江、赣南等地区金矿找矿中的初步应用。 相似文献