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阐述了全站仪在公路施工中的施工平面控制点加密,中桩测设,构造船桥梁施工工细部控制的方法以及精精度,指出了全站仪使用注意事项。 相似文献
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目前测绘部门在选用徕卡OSW系统中的TC1800全站仪和TC1500全站仪,这些均为TPS1000系列。全站仪内存为4MB,带有PCMCIA卡槽,并有用户自编程序使用功能,外业数据记录可用PCMCIA卡(1MB—4MB),通过HP—200英文掌上电脑打印报表。 目前海测部队已装备TC1500全站仪,为开发徕卡TC1500全站仪海控测量各种应用软件的硬件设备已经具备。 徕卡TC1500全站仪硬件内存有4MB,系统软件最多占用1MB,还有3MB内存,完全可以开发所有海控测量外业记录和内业处 相似文献
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阐述了桥梁施工中的特殊条件下,桥位控制网的布设,认为采用全站仪极坐标法放样时,可以完全不测设过过去的桥梁施工所布设的施工控制网,桥梁控制点应灵活布设。 相似文献
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全站仪自由设站应用于航道控制测量的图形研究 总被引：4，自引：1，他引：3
利用全站仪自由设站测边交会确定待定点的坐标,在航道控制测量工作中得到较好的应用。为研究待定点的精度与交会图形之间的关系,在推出全站仪自由设站测边交会精度估算公式的基础上,对其有利图形进行了分析,并通过实例证明:当采用对称交会(β1=β2),且交会角γ>90°时,交会图形最为有利。 相似文献
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TCM电动全站仪是一种具有自动照准预设方向、能自动纵转望远镜,EDM迅速准确连接,能用RS232接口输出数据的全新马达驱动的电子全站仪。其配置的自动跟踪目标装置ATR1与全站仪测距系统及视线同轴,即使对在仰角和倾角很大的测点目标也能追踪如常。TCM电动全站仪配置GRZ4 360°全反射棱镜,使得持标员无需顾及棱镜反射面是否对准全站仪。TCM电动全站仪有效工作距离在一般大气条件下,ATR1全反射棱镜的工作距离为1000m(可满足大比例尺海上测绘范围 相似文献
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Jonaotaro Onodera Kozo Takahashi 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(2):189-211
Long-term monitoring of diatom fluxes during 1990–1998 was conducted at Station AB in the Bering Sea and Station SA in the central subarctic Pacific in order to decipher the relationships between sinking diatom and the upper water mass environments. The total diatom flux at Station AB was generally twice as high as that at Station SA. The dominant species in the sinking flora was primarily Neodenticula seminae at both stations, which was a significant contributor to organic carbon flux. The flora at Station AB was represented by relatively abundant coastal taxa including Chaetoceros resting spores. These results suggest more favorable conditions for diatom production at Station AB compared with those at Station SA. The possible influences of oligotrophic and temperate water masses were discerned from the positive SST anomaly and the occurrence of a few specimens of temperate species. The cumulative annual fluxes of total diatoms at Stations AB and SA are apparently related to the variation in the mean annual depth of mixed layer. At Station SA, annual mean of total diatom flux showed a negative correlation with the Pacific Decadal Oscillation (PDO) Index, which suggests a significant relationship between surface water turbidity and diatom production. At Station AB, the annual change of coastal diatom flux was correlated with the PDO and the winter value of the Arctic Oscillation, which may suggest a significant influence of Alaskan Stream waters via the Aleutian Islands and intensity of surface water mixing. 相似文献
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A 9-year study of planktonic foraminifer fluxes was conducted in the Bering Sea (Station AB) and in the central subarctic Pacific (Station SA). Results clearly reflected variations of the water mass characteristics in the upper layers. The 9-year means of total foraminifer fluxes were the same (1400 shells m−2 d−1) at both stations. However, total foraminifer flux at Station AB tended to show its primary maximum during fall (October–December) and its secondary maximum in spring (April–June), whereas the primary maximum appeared in spring and the secondary maximum in fall at Station SA. Seasonal variation was more apparent at hemipelagic Station AB than at pelagic Station SA. Planktonic foraminifers found at both stations were of six species: Neogloboquadrina pachyderma, Globigerina umbilicata, Globigerinita glutinata, Globigerina quinqueloba, Globorotalia wilesi, and Orbulina universa. The foraminifer assemblages at the two stations reflected the temperature difference in the surface waters. The variable %G. umbilicata tended to be high in the warm surface waters during the summers. The temporal and geographical variation of %G. quinqueloba indicated that this taxon prefers regions with relatively low diatom fluxes. A notable appearance of O. universa occurred in 1997 at Station SA. During this period, other measured biogenic particle fluxes, such as those of diatoms, were low. This unusual 1997 event may be a reflection of global climatic change that happened to be observed in the central subarctic Pacific Ocean. 相似文献
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The effect of salinity on the distribution of copepoda in the Jiulong Estuary is studied in the present paper. The analysis of the samples collected during February 1983-January 1984 shows that the salinity of the Jiulong Estuary varies from 0.04 at Station E (head of estuary) to 31.7 at Station C (mouth of estuary). The distribution of copepoda is obviously affected by salinity. The results of the investigation show that the number of species, Shannon-Weaver H' index of diversity, species richness d and species evenness J' of copepoda increase with increasing salinity. Especially between the Station D and the Station C, being dominated by three predominant species. But, on the other hand, the total number of individuals apears to decrease with increasing salinity. According to the relation of distribution of copepoda with salinity, the copepoda may be divided into five ecological groups, i.e. fresh-water, low-salinity estuarine, meso-salinity estuarine, neritic and oceanic groups. Their horizontal succ 相似文献
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F. V. Kashin V. F. Radionov E. I. Grechko 《Izvestiya Atmospheric and Oceanic Physics》2007,43(4):490-496
The results of measuring the total contents of carbon monoxide and methane via the method of solar-absorption spectroscopy are presented. The measurements were performed at the Molodezhnaya Station in 1977–1978, at the Mirny Observatory from 1982 to 1992, and at the Novolazarevskaya Station from 2003 to 2006. The character of seasonal variations in the contents of these gases in the Antarctic atmosphere is described and compared to the intra-annual variation of their surface concentrations measured at the Syowa Station (Japan). Synchronous intra-annual variations in the contents of carbon monoxide in the atmospheric column and in its surface concentrations are observed, while the spring maximum content of methane is observed three months after the maximum of its surface concentration. Synchronous seasonal variations in the total content of methane and ozone are observed, which makes it possible to suggest that the Antarctic circumpolar vortex has a significant influence on the characteristics of the vertical distribution of methane during Antarctic spring. Quantitative estimates of the parameters of multiyear variations in the contents of CO and CH4 are given. The content of methane was increasing (although with different rates) during the entire observation period 1977–2006. The content of CO was observed to increase until 1992 and to decrease during 2003–2006. 相似文献
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Roberto Danovaro Norberto Della Croce Anastasios Eleftheriou Mauro Fabiano Nadia Papadopoulou Chris Smith Anastasios Tselepides 《Progress in Oceanography》1995,36(4)
Quantitative information on the abundance and biomass of metazoan meiofauna was obtained from samples collected at 15 deep-sea stations in the Eastern Mediterranean Sea (533–2400m). Meiofaunal abundance was compared to bacterial biomass and other environmental factors such as the total sedimentary organic matter content, the concentrations of the main biochemical classes of organic compounds (i.e. proteins, carbohydrates and lipids) and to ATP. To estimate the sedimentation potential of primary organic matter, sediment bound chloroplastic pigment equivalents (CPE) were assayed. Meiofaunal density was very low ranging from 4 ind.10cm−2 (Station A4, 1658m depth) to 290 ind.10cm−2 (Station A12, 636m depth). Nematodes were the numerically dominant taxon (68% of total meiofauna) and were usually confined to the top 6cm of the sediments. Total meiofaunal biomass ranged from 2.78μgC 10cm−2 (Station A4) to 598.34μgC 10cm−2 (Station 15A). There was a significant decrease in the density of metazoan meiofauna with water depth. Bacterial biomass largely dominated the total biomass (as the sum of bacterial and meiofaunal biomass) with an average of 73.2% and accounted for 35.8% of the living biomass (as ATP carbon) whereas meiofaunal biomass accounted only for 6.56%. Bacterial biomass was significantly related to the DNA concentrations of the sediment. A significant correlation between ATP concentration and CPE content was also found. No correlations were found between meiofauna, ATP and CPE, or between meiofauna and bacterial parameters. The significant relationship between meiofaunal density and the ratio of labile organic matter/total organic matter indicates that deep-sea meiofauna inhabiting an extremely oligotrophic environment (such as the Eastern Mediterranean) may be more nutritionally dependent upon the quality than on the quantity of sedimentary organic matter. 相似文献
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《Deep Sea Research Part I: Oceanographic Research Papers》2000,47(9):1723-1759
Time-series sediment traps were deployed for five consecutive years in two distinctively different subarctic marine environments. The centrally located subarctic pelagic Station SA (49°N, 174°W; water depth 5406 m) was simultaneously studied along with the marginal sea Station AB (53.5°N, 177°W; water depth 3788 m) in the Aleutian Basin of the Bering Sea. A mooring system was tethered to the sea-floor with a PARFLUX type trap with 13 sample bottles, which was placed at 600 m above the sea-floor at each of the two stations. Sampling intervals were synchronized at the stations, and they were generally set for 20 days during highly productive seasons, spring through fall, and 56 days during winter months of low productivity. Total mass fluxes, which consisted of mainly biogenic phases, were significantly greater at the marginal sea Station AB than at the pelagic Station SA for the first four years and moderately greater for the last year of the observations. This reflects the generally recognized higher productivity in the Bering Sea. Temporal excursion patterns of the mass fluxes at the two stations generally were in parallel, implying that temporal changes in their biological productivity are strongly governed by a large-scale seasonal climatic variability over the region rather than local phenomena. The primary reason for the difference in total mass flux at the two stations stems mainly from varying contributions of siliceous and calcareous planktonic assemblages. A significantly higher opal contribution at Station AB than at Station SA was mainly due to diatoms. Diatom fluxes at the marginal sea station were about twice those observed at the pelagic station, resulting in a very high opal contribution at Station AB. In contrast to the opal fluxes, CaCO3 fluxes at Station AB were slightly lower than at Station SA. The ratios of Corg/Cinorg were usually significantly greater than one in both regions, suggesting that preferentially greater organic carbon from cytoplasm than skeletal inorganic carbon was exported from the surface layers. Such a process, known as the biological pump, leads to a carbon sink which effectively lowers p CO2 in the surface layers and then allows a net flux of atmospheric CO2 into the surface layer. The efficiency of the biological pump is greater in the Bering Sea than at the open-ocean station. 相似文献
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全面总结了土层预应力锚索技术在广州地铁二号线火车站地铁车站中的应用及其配套技术 ,着重介绍了预应力锚索的施工方法、监控测量对施工效果的分析。 相似文献
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珠江口以东近海水域污损生物的组成与分布 总被引：4，自引：0，他引：4
于１９８６年５月至１９８７年６月期间,在珠江口以东近海水域,距岸分别为１５．７和７１．７ｋｍ、水深２７和７１ｋｍ两处布设Ｚ１和Ｚ２两个浮标调查站,以研究该海区污损生物的组成及分布状况。结果表明,在相对近岸的Ｚ１站,各水层的污损生物均以无柄蔓足类、海葵和双壳类及多毛类等华南沿岸海区常见种类为主,其中网纹藤壶占绝对优势;而远岸的Ｚ２站,则主要是有柄蔓足类和水螅,且生物的种类和数量也远远低于Ｚ１站。 相似文献
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我国南极科考站附近气旋的特征分析 总被引：1，自引：1，他引：0
本文基于欧洲中心的ERA-Interim再分析数据,采用雷丁大学的气旋自动识别与追踪算法,建立了1979-2013年中国南极科学考察站长城站、中山站以及泰山站划定的统计区域内气旋数据集。基于这套数据,分析了3个站区附近气旋的气候特征,包括:气旋数量、空间分布、强度、加深率等,并研究了达到爆发性发展的气旋的时空特征。分析表明,长城站以及中山站气旋数量均有增加趋势,但都未达到显著水平;泰山站气旋数量的减少趋势达到显著性水平。3个站区的气旋统计表明,长城站统计区域内气旋活动最频繁,且爆发性气旋活动相对较多;中山站、长城站气旋的数量和空间分布具有季节变化,气旋数量夏季较其他3个季节偏少、偏弱;泰山站气旋活动最少,并且大部分影响到该站的气旋都处于消亡阶段,气旋的强度较弱,故气旋活动对该站的影响较弱。 相似文献