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1.
基于2013年高教杯数学建模竞赛C题完成的对古塔的变形情况进行研究,针对古塔的倾斜、弯曲、扭曲等方面进行研究分析,并建立相应的数学模型。首先利用给空间平面拟合法确定古塔各层中心位置的通用方法,求解出古塔各层中心坐标;其次计算古塔的倾斜程度以及弯曲、扭曲的变形程度。最后,分析古塔的变形趋势。根据所建模型,得出古塔的变形趋势,对古塔的保护具有很大的指导意义和使用价值。  相似文献   

2.
提出一种新的古塔倾斜测量及质量评价方法.针对古塔层层收分、斗拱檐口及棱角模糊导致变形测量特征点难以确定的问题,提出利用圆拟合的方法确定古塔各层中轴点.在古塔中心轴线拟合中,引入整体最小二乘法进行平差解算,克服了系数矩阵存在误差的问题.除计算古塔整体倾斜度,还计算各层倾斜度和扭曲度以反映古塔的详细变形情况.相比传统的简单利用塔顶和基座的相对位移和塔高来计算古塔倾斜的变形检测方法,采用多层中轴点拟合的检测方法更加准确和详细地反映了古塔的变形.  相似文献   

3.
根据某古塔现有观测数据得知,其所有中垂线不交于一点但取值范围集中,故采用求取均值建立中心点坐标数学模型,结果可信度高,进而得到古塔变形的倾斜角。通过MATLAB计算绘制古塔倾斜度和倾斜角及其比较图和古塔三维立体图,直观分析了古塔弯曲和扭曲情况。由于系统模型不明确、信息不完整,故采用灰色理论建立了古塔变形趋势的预测模型,预测了古塔的变形趋势。由模型评价标准证明了模型的准确性和可靠性。  相似文献   

4.
通过对具有上千年历史某古塔的不连续4年数据的分析和处理,以曲线拟合为基础,对变形观测数据进行分析处理,求解出每层中心坐标。利用中心坐标,计算古塔倾斜度、曲率、扭曲夹角等指标分析古塔变形情况,用灰色预测法建立古塔的倾斜度的预测方程模型。  相似文献   

5.
针对古塔的变形问题,根据所给的四年观测数据,利用塔层散点原始数据及其投影分别拟合确定古塔各层中心点的位置,根据观测点数据和中心点位置分析该塔的倾斜、弯曲、扭曲情况,关于时间作拟合,推测出未来古塔的变形趋势.  相似文献   

6.
中国古塔由于外界环境、时间变化、人为损毁等因素的影响而产生形变,变形的因素有很多,我们主要对古塔的变形量:倾斜、弯曲和扭曲这3个方面进行分析研究,对这些影响因素做更为精确的量化.利用每一层中心点构成的直线与原始的中心轴构建直角三角形,计算得出塔的倾斜角度,用倾斜角θ来量化古塔的倾斜程度.通过研究古塔每个顶点在地面的投影,利用计算机Mathmatica软件作古塔顶点集在地面投影的直线函数拟合,从而计算扭转后与扭转前两条直线的夹角α,用扭转角度来衡量古塔的扭曲程度.通过分析古塔倾斜角和扭曲度随着时间的变化情况,从而来估测n年以后古塔的变形情况.  相似文献   

7.
韩侃  卢波  方建生  李建章 《甘肃科技》2015,31(3):107-110
根据古塔的特点、现状,借鉴其他类似监测项目的测量经验,从理论分析、现有技术手段和可能的技术措施人手,对古塔建筑物平面位移和垂直位移的监测方法进行了对比,并运用相互校核的监测方法对古塔建筑物的倾斜做了详细阐述。利用平均间隙法原理,对监测网基点的稳定性进行了检验及分析,提出了基于回归平面的古塔变形的分析方法,结合塔体上监测点平面坐标及沉降量回归平面,从而确定沉降量及倾斜率。探讨了Trimble GX三维激光扫描仪在古塔建筑物变形监测中的应用,该仪器能够快速识别并捕获相关数据,弥补了传统变形监测的片面性和局限性。综合分析各种检测方法的检测结果,得出了可靠的结论。  相似文献   

8.
吉耀武 《河南科学》2014,(10):1957-1962
古塔是我国重点保护文物,为保护古塔,文物部门对古塔进行观测,了解各种变形量,以制定必要的保护措施,借用文物部门的4次观测数据,首先对1986年和1996年缺失数据进行补充,利用完整的数据拟合每层各测量点所在平面,将各点投影到平面上,得到每层各中心点坐标的通用模型.对中心点作线性拟合,利用中轴线与水平面法向的夹角得出度量倾斜的模型;对中心点作三次样条拟合,利用拟合曲线各点曲率得出度量弯曲的模型;利用拟合的相邻平面的旋转角得出度量扭曲的模型.最后使用MATLAB编程计算模型变形数据,可以检测古塔各层的变形情况,为文物部门制定相应的保护措施提供可靠依据,该模型也可以推广到其他建筑物的变形测量中.  相似文献   

9.
采用粒子群算法求出古塔各层的中心点坐标,并对塔层中心进行空间直线拟合.根据拟合直线的方向向量算出塔体每年偏转角度的近似值.对塔层中心的投影点作直线拟合,以投影点在拟合直线上的疏密程度判断塔体局部弯曲程度;以投影点偏离拟合直线的远近及分布判断塔体局部的扭曲程度.研究结果为古塔变形趋势研究提供了新方法.  相似文献   

10.
古塔是古代高层建筑的杰出代表,研究古塔在地震作用下的表现对于保护古塔具有重要意义。本文通过结合脉动试验数据和模态分析结果,运用振型分解反应谱法预测了某古塔的震害情况,为有关部门保护古塔提供参考。  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.
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   

13.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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