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1.
晏志伟  潘卉  乔玲玲  李逊 《水文》2015,35(1):73-76
介绍了用断面资料推求流量的基本原理和方法,提出了该方法的适用条件。以马良坪站2010年的实测资料为实例应用本方法推求单一的水位流量关系曲线,进一步说明了本方法的适用条件。通过对推求的水位流量关系曲线与当年实测的水位流量关系曲线对比,说明了该方法在其适用的条件下能满足无流量资料条件下的水情报汛和水文应急服务的要求。  相似文献   

2.
拉格朗日乘子法在水位流量关系拟合中的应用   总被引:1,自引:0,他引:1  
周世良  尚明芳  李怡  刘小强 《水文》2011,31(5):15-17,71
针对传统方法在水位流量关系拟合中线性化后存在的不足以及未考虑拟合函数的显著性水平的局限性,以流量残差平方和最小为目标函数,以显著性水平为约束条件,结合拉格朗日乘子法对水位流量关系进行优化处理。通过算例对比分析了水位流量关系在传统算法、自适应加速遗传算法及本文优化算法下的拟合结果。计算结果表明:提出的优化理论能更精确地模拟实际工程中水位流量关系,其基本思想可为类似的水文分析提供借鉴作用。  相似文献   

3.
受洪水涨落影响下稳定水位流量关系直接计算   总被引:4,自引:1,他引:3  
根据洪水涨落影响下的同水位涨落水面流量公式,推导出计算稳定流量Q0的数字表达式,并论述了表达式中未知量S1/S2(同水位涨落水时附加比降的比值)计算的方法原理。从而可根据实测洪水绳套和水位过程直接计算稳定的水位流量关系曲线。  相似文献   

4.
一、前言在廿年前西津水电站设计时,曾遇到两个水文计算上的问题:第一个问题,西津是低水头河床式电站,厂房设计水位由下游天然水位流量关系曲线控制,但西津历年的水位流量关系曲线均不相同,在设计流量情况下,查上包线和下包线水位相差2  相似文献   

5.
在水文計算工作中,有时需要在缺少实測流量資料情况下繪制水位流量关系曲线。現今常用的有两种基本方法:一种是根据相应水位引借流量关系曲线;一种是根据謝才公式繪制。 利用相应水位法,要在邻近断面有水位流量关系曲线,而且两个断面的水位关系必須十分密切。 由于糙率选择任意性較大,确定河段水面比降也上匕較麻煩,因此采用謝才公式来計算水位流量关系曲  相似文献   

6.
小龙潭水库坝址的尾水受小龙潭下游伏流的影响,伏流消水洞的排泄能力较差,洪水常形成壅水,不能按常规曼宁公式进行计算坝址尾水的水位与流量关系,根据伏流消水洞的泄流能力按"水库调洪"方法计算绘制小龙潭水库坝址建库后水位流量曲线,确定坝址尾水水位流量关系。结果表明:下游伏流消水洞泄量较小,水库施工期间可能受下河石渣影响。因此,施工过程中要密切注意施工弃渣和弃石,并即时对其进行清理,避免堵塞下游河道。并且下阶段应设立水位、流量监测站,积累资料,即时复核水位流量关系。  相似文献   

7.
周下平 《水文》2007,27(1):66-68
目前,水位流量关系受单一因素影响的拟合,已有了比较成熟的方案,但对于受多因素影响的水位流量关系的拟合,尚没有理想的方案。多方案加权模型就是基于多因素影响的水位流量关系而建立的,本文运用了系统理论方法和数理统计理论对多方案加权模型从理论上进行了分析,并通过对湖南省朗梨水文站的实测水位流量资料的拟合,对其有效性进行了探讨。  相似文献   

8.
谢大勇  陶铁林等 《水文》2001,21(4):44-48
渤海岸六股河绥中站是典型的复式河槽站,根据历史资料,用经验分析及推理的方法提出了多股水流条件下平均水位的计算公式,并以此计算日平均水位及建立水位流量关系进而推求日平均流量,可获得满意的效果。  相似文献   

9.
梁才贵 《水文》2002,22(5):51-55
2001年7月上旬,受3、4号台风影响,郁江发生了继1937年大洪水以来的最大洪水,各水文站对洪水进行了非常全面的流量测验,大部分站的实测水位流量关系与多年综合相差不大,但下颜、南宁和贵港水文站相差较大,其中下颜和南宁站严重偏小,而贵港站严重偏大。通过洪量平衡分析,认为这3个站的实测水位流量关系与多年综合相差较大的根本原因是实测流量问题。  相似文献   

10.
一、引言国际标准化组织在1980年印发了国际标准草案 ISO/DIS1100/2“水位流量关系之确定”。其中,规定了水位流量关系检验的方法。第一种检验就是 t 检验。如果,在一个水文站的水位流量关系已经定出之后,过了一段时间,又进行了一些校核测量,这时,就要用原来定线的点据和后来校核的点据,进行这种检验。检验水位流量关系曲线是否已经发生了变化。如果认为并未发生显著变化,就可继续使用原定曲线;如果认为已经发生了显著变  相似文献   

11.
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.  相似文献   

12.
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.  相似文献   

13.
14.
Chronological analyses of correlations between certain global repeating events (mass extinctions of marine organisms, meteorite impacts, and flashes in the frequency of geomagnetic reversals) during the Phanerozoic Eon and the motion of the solar system in the Galaxy are presented for five rotationally symmetrical models for the regular Galactic gravitational field. Thirteen of sixteen mass-extinction events can be described by a repetition interval of 183±3 million years. This is in agreement with the anomalistic period (interval between two subsequent passages of the Sun through the apocenter of its Galactic orbit) in the model of Allen and Martos. The positions of the minima and maxima in Gaussian functions approximating the frequency distribution for geomagnetic reversals also agree with the times of passage of the Sun through the apocenter and pericenter, respectively, of its Galactic orbit in this model. The maximum in the distribution of the deviations of the dates of mass extinctions from the nearest dates of impacts of large, crater-forming bodies is close to zero, providing evidence that many such events are correlated. As a rule, extinctions follow impact events. The impacts of large bodies have occurred most often when the solar system passes through the Galactic plane, while mass extinctions occur more often at some distance from the Galactic plane (about 40 pc). As a rule, intervals of increases in the frequency of geomagnetic reversals coincide with dates of impacts of large bodies. At the same time, these intervals do not show a clear correlation with the dates of mass extinctions. The intensity of mass extinctions, like the energy released by impacts, is consistently higher in periods when the Sun is moving from the apocenter toward the pericenter of its orbit, than when it is moving from the pericenter toward the apocenter. Thus, there is evidence for a variety of relationships between repeating global events in the Phanerozoic and the motion of the Sun in the Galaxy. Long-period variations in the frequency of geomagnetic reversals are correlated with the orbital motion of the Sun, and increases in the frequency of geomagnetic reversals are correlated with impacts. Mass extinctions are correlated with the impacts of large bodies, whose motions may have been perturbed by clouds of interstellar material concentrated toward the Galactic plane and by the shock front associated with the Perseus spiral arm, through which the solar system passes. The velocity of the Sun relative to the spiral pattern is estimated.  相似文献   

15.
从榴辉岩与围岩的关系论苏鲁榴辉岩的形成与折返   总被引:4,自引:1,他引:4       下载免费PDF全文
位于华北和扬子两板块碰撞带中的苏鲁榴辉岩形成的温压条件不但是超高压,而且是高温。榴辉岩的PTt轨迹表明其为陆-陆磁撞俯冲带的产物。榴辉岩的区域性围岩花岗质片麻岩为新元古代同碰撞期花岗岩,榴辉岩及其他直接围岩皆呈包体存在于其中,并见新元古代花岗岩呈脉状侵入榴辉岩包体中。区域性围岩新元古代花岗岩的锆石中发现有柯石英、绿辉石等包裹体,表明新元古代花岗岩的组成物质也经受过超高压变质作用,且榴辉岩与围岩新元古代花岗岩的锆石U-Pb体系同位素年龄基本相同。但新元古代花岗岩所记录的变质作用和变形作用期次(或阶段)却少于榴辉岩。椐上述可得如下推断:超高压榴辉岩与新元古代花岗岩岩浆是同时在碰撞带底部(俯冲板块前部)形成的;榴辉岩的第一折返阶段是由新元古代花岗岩岩浆携带上升的,其第二折返阶段是和新元古代花岗岩一起由逆冲及区域性隆起而上升,遭受剥蚀。  相似文献   

16.
某高速公路下伏煤矿采空区稳定性分析   总被引:10,自引:0,他引:10  
在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。   相似文献   

17.
18.
摩擦桩基桩土间极限摩阻力取值问题探讨   总被引:1,自引:0,他引:1  
陈银生 《世界地质》1999,18(1):54-59
通过对广珠东线高速公路横沥大桥的试桩及土体的工程地质条件分析,总结出影响摩擦桩基桩土间极限摩阻力取值的一般问题以及解决问题的方法和措施。  相似文献   

19.
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.  相似文献   

20.
The structure of the eastern Pyrenees consists mainly of south-directed thrusts involving basement and cover rocks. An antiformal stack developed by the piling up of basement thrust sheets which outcrop in the Axial zone. These structures account for a thin-skinned thrust model rather than a vertical fault model in which the Axial zone would be essentially autochthonous, and the North-Pyrenean fault the axial plane of a fan thrust system. New data from the Eastern Pyrenees and the thin-skinned model suggest that(1) the structure east of the Pedraforca nappe is similar to that of the Central Pyrenees; (2) the cover rocks of the South-Pyrenean units and of the Axial zone-after restoration—built up a northwards-thickening prism consistent with the existence of a unique Pyrenean sedimentary basin during Mesozoic time; (3) the Axial zone is only a complex antiformal stack developed as a part of South-Pyrenean system related to the Paleogene thrusting-tectonics. The Axial zone palaeogeographic area had no special meaning during Mesozoic time.  相似文献   

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