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1.
叙述了重力法(斯托克司方法,莫洛金斯基理论)和GPS水准相结合精化区域(似)大地水准面的方法,并利用模型对GPS网点似大地水准面和正常高的确定提出了编写应用软件的思路。结合项目检验证实,该项成果达到了设计要求,并且已经在测绘工作中发挥了巨大的作用,充分发挥了GPS测量方便、省时、省力、精度高、成本低等优点。  相似文献   

2.
重力位模型和GPS/水准数据确定区域似大地水准面   总被引:2,自引:2,他引:0  
为了有效的利用GPS观测的高程信息,实现GPS观测值中的椭球高向正常高转化,采用EGM96和EIGEN-CG01C重力位模型和某区域的GPS/水准观测数据,应用几何方法确定了该区域1.5'×1.5'分辨率的似大地水准面格网数值模型.该似大地水准面模型内插高程异常与实测GPS/水准点的高程异常进行比较,内符合精度和外符合精度均优于0.040米.表明在地形平坦地区,用平均点间距为10KM的GPS/水准点成果,可以确定厘米级的似大地水准面模型,结合GPS观测成果可以取代四等及以下几何水准测量.  相似文献   

3.
似大地水准面与大地水准面的精密转换   总被引:3,自引:0,他引:3  
提供了似大地水准面转换与大地水准面的精密公式和实施方法,其中涉及扰动重力垂直梯度,转换后的大地水准面的精度与前者相近.  相似文献   

4.
苗龙 《科技咨询导报》2009,(15):105-105
我院承担完成的昌吉准东煤化1:10000地形图基础测绘项目,采用了GPS单点定位辅助摄影技术,运用似大地水准面模型计算出摄站中心的正常高,具体方法是利用地面已有的基础控制点,用GPS/水准法确定该区域内的似大地水准面模型,然后运用该模型解算出航摄像片摄站中心的正常高,并且通过数据分析了本区域内所建立GPS水准似大地水准面模型的精度。  相似文献   

5.
GPS高程转换中,经常用到的方法是GPS/水准法,对于缺乏地面重力数据的地区,该方法不是十分理想.本文采用一种组合方法来解决该问题,利用EGM2008模型和GPS/水准数据确定局部似大地水准面,结合工程实例,利用带状线路数据进行曲线拟合,验证的结果表明,采用组合方法进行正常高计算效果显著.  相似文献   

6.
GPS所测高程是相对于WGS-84的大地高,而我们在实际生产中应用的是相对于大地水准面的正高或相对于似大地水准面的正常高,为了确定与计算在温州地区的大地水准面上的拟合高程,本文通过利用OSU91A模型对GPS高程平差的影响,以便合理地来计算平差GPS拟合高程,作以抛砖引玉之旨,望各位专家及同行不吝指正。  相似文献   

7.
为了对在似大地水准面精化中的应用,利用TGO软件解算基线和网平差与GAMIT软件结合TFORM工具两种不同的方法分别处理GPS观测数据,获取大地高,同时利用三等水准数据获取正常高,再利用大地高和正常高的关系,在不考虑重力场模型和重力数据等影响的前提下,用二次曲面方法来拟合高程异常,在某市作了验证,两者的内符合精度相当,均能满足四等水准的精度要求.  相似文献   

8.
介绍了大地水准面精化的意义和精化大地水准面的3种方法,用GPS/水准重合点的高程异常,建立了区域大地水准面的几种数学模型并做了实验和精度分析。  相似文献   

9.
在由似大地水准面过渡到大地水准面的进程中 ,一定要顾及高程二次项 (H2 )的改正 ,在此基础上 ,推求了洱海中海岛的大地水准面与正高 ,它们分别为 (- 31.41± 0 .6 8)m和 (2 0 0 0 .41± 0 .10 )m .文中对 ζ -N中改正项的数学与物理意义也作了阐述 .  相似文献   

10.
根据当前的国际天文背景和实际需要论述了大地水准面概念的局限性和建立相对论大地水准面的必要性,采用广义相对论天体力学理论给出了大地水准面的两种形式的推广,指出了其中1阶后牛顿(1PN)等时面适合作为1PN大地水准面的定义,在目前和不远的将来可以满足天文和相关领域应用上高精度的需要.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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