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1.
During the end of the 20th and the beginning of the 21st centuries, interest has risen in new and renewable energy sources, and especially wind energy for electricity generation. In a short time, wind energy has been welcomed by society, industry and politicians as a clean, practical, economical and environmentally friendly alternative to existing fossil fuels. As a result of extensive studies on this topic, wind energy has recently been applied in various industries, and has started to compete with other energy resources. Wind energy applications and turbine installations at different scales have increased since the beginning of this millennium. Technically installed wind turbines capacity factors have high values in most areas of Turkey. It is seen that, in general, the modeling of wind speed and its parameters have been studied and researched rather than wind power technological development in Turkey. Wind investors had doubts about uncertainties in the renewable energy policies. After May 2007, an energy efficiency law was accepted and 10 years of electricity generation by renewable sources is considered as guaranteed by the Turkish government. The installed wind power has reached 131.35 MW in Turkey and it is expected that this value will be increased to 808.81 MW by the end of 2008. The dependence of strong technological and economical development on Turkey's energy needs have increased and new national or international sources have to be taken into account for the energy sector of the country. It is clear that this source gap could be filled by using the high potential of wind power, which is estimated at 58 GW. It is expected that installed wind power to supply up to 5% of electricity consumption by 2015 and for the end of 2008 this ratio will increase to 2% (it is currently ca. 1.0%). However, unexpected and unpredicted wind power applications have occurred on November 1st, 2007 in Turkey. It has been announced that 78,000.00 MW wind power investments have been applied by the Energy Market Regulatory Authority (EMRA). This is a new era for the Turkish energy sector and there is no model for this new situation. Therefore, in this paper, wind energy in Turkey is reviewed and opened up for further discussion.  相似文献   

2.
The use of time domain and frequency domain techniques in the analysis of geomorphological time series is discussed and the techniques of spectral analysis are introduced. An Excel worksheet is used to analyse wave-current data from Slapton Sands in Devon and the advantages and limitations of the technique are listed.  相似文献   

3.
重力位场谱分析方法研究综述   总被引:3,自引:1,他引:3       下载免费PDF全文
陈石  张健 《地球物理学进展》2006,21(4):1113-1119
利用Fourier变换将空间域位场数据变换到频率域进行谱分析是重力位场数据处理中的一种重要方法.这种方法在位场的延拓及转换、场分离、物性界面的正反演和位场的曲化平处理等方面已得到广泛的应用.本文详细介绍了位场谱分析的基本理论和方法,总结了国内外最近几十年来在这方面取得的主要成果,并提出了未来值得深入研究的方向.  相似文献   

4.
The development of wind power installations globally and in Turkey is reviewed here. Firstly, the growth of global installed wind power capacity between 1996 and 2007 is reviewed, and the top countries in terms of total installed wind power capacity by region are identified. Then, wind power installation and its development in Europe are discussed. In addition, the current status and development of Turkey's wind power plants are investigated in detail.  相似文献   

5.
海陆风及沿海风速廓线在风电场风速预报中的应用   总被引:3,自引:1,他引:3       下载免费PDF全文
为了建立沿海风功率预报系统,本文探讨了中国沿海风电场风速预报问题,并利用数值模式RAMS对海陆风进行了模拟研究.发现海陆风发生时,海风和陆风阶段风速廓线存在较大差异,海风阶段风速的垂直切变明显小于陆风阶段.海陆风发生时,风速会呈现有规律的变化,即海风和陆风分别有两个时段:风速增加时段和风速减少时段.在为沿海风电场提供风速预报时,当模式预报到海陆风发生时,可以利用海陆风的这种特点,使用统计方法对预报出的风速进行有效的订正.并发现即使没有海陆风发生,当风向为海洋吹向陆地时,风速随高度的垂直切变同样小于陆地吹向海洋的时段.利用统计方法根据不同风向时风速廓线的特性,把数值模式计算高度上的预报结果,精确地插值到风机涡轮高度,会很大程度上减少风速预报的误差及风功率预报环节的误差.  相似文献   

6.
Spatial variation of the surface micro‐relief in a Sharkey clay soil was investigated. The micro‐relief measurements of the soil surface were obtained using an automated infrared laser system and evaluated with methods of Fourier analysis. The authors illustrate the spectral technique with a simple example and then use the technique to interpret the surface micro‐relief patterns of soil samples subjected to three simulated rainstorm intensities. The periodicity of the soil surface micro‐relief in the longitudinal direction was 80–120 mm. The periodic surface micro‐relief patterns immediately following the rainstorm are shown to be an early manifestation of the cracking pattern. Published in 2006 by John Wiley & Sons, Ltd.  相似文献   

7.
 Water levels of the five river stages in the Taipei Basin are analyzed by using spectral analysis in time-frequency domain through one-year hourly data. The autospectral and cross-spectral density function, coherence, phase angle and associated statistic parameters are studied. The semi-diurnal, diurnal and quarter-diurnal tidal components are significant for river stages, which are also apparently related to astronomical tides of M2, S2, N2, S1, O1 and M4, MK4 or MS4 respectively. The time lags versus propagation distance are shown as linear distribution for two stream systems. The time lags are 3.2, 4.0 and 2.5 (h) for semi-diurnal, diurnal and quarter-diurnal components in Tanshui River – Tanhan Stream system, while 3.5, 3.5 and 2.2 (h) in Tanshui River – Hsintien Stream system. This research was supported by the Institute of Nuclear Energy Research(INER), Atomic Energy Council, Taiwan, Republic of China, under the fund of the Executive Yuan. The author appreciates Taiwan Provincial Government Water Resources Department and Central Weather Bureau for providing useful data.  相似文献   

8.
9.
The accuracy of an optimum interpolation technique in filling missing values in multichannel (or multisite) hydrologic series containing time-coincident data gaps is examined. The applied methodology is based on the maximum entropy method (MEM) of spectral estimation or multivariate autoregressive modeling and heavily depends upon the properties of multichannel prediction error filter (PEF). Six precipitation time series spatially located within a hydrologic basin are used and time-coincident artificial gaps are created in all six series. The performance of the technique is assessed by comparing the filled-in series to the observed and by employing spectral analysis. The results reveal the usefulness of the method in multichannel hydrologic analysis.  相似文献   

10.
The accuracy of an optimum interpolation technique in filling missing values in multichannel (or multisite) hydrologic series containing time-coincident data gaps is examined. The applied methodology is based on the maximum entropy method (MEM) of spectral estimation or multivariate autoregressive modeling and heavily depends upon the properties of multichannel prediction error filter (PEF). Six precipitation time series spatially located within a hydrologic basin are used and time-coincident artificial gaps are created in all six series. The performance of the technique is assessed by comparing the filled-in series to the observed and by employing spectral analysis. The results reveal the usefulness of the method in multichannel hydrologic analysis.  相似文献   

11.
The basal depth of the outer layer with internal magnetic sources was calculated from magnetic data available within a roughly 500 km wide and 1200 km long area, running from central Germany to southern Italy. The dataset, deriving from different aeromagnetic surveys, is reduced to the reference altitude of 3000 m a.s.l. and a reference year of 1980.0. The adopted method, which transforms the spatial data into the frequency domain, provides a relationship between the two-dimensional spectrum of the magnetic anomalies and the top and centroid depths of the magnetic sources. The magnetic layer bottom depth (MLBD) thus obtained is 29-33 km deep in the stable areas (central Europe Variscan units, Corsica-Sardinia Variscan block) and corresponds to the Moho, having an average temperature of 560 °C. From the Alps to the Apennines, MLBD ranges between 22 and 28 km and is clearly shallower than the Moho. In these units, the wide variation of MLBD appears to be compatible with the presence of shallow magnetised bodies, consisting of lower crustal rocks (Ivrea-Verbano zone), ophiolitic units (Penninic zone and Voltri Massif) and intrasedimentary basic volcanic bodies (Po Basin). An average value of 25 km can be attributed to MLBD, which corresponds to a temperature of 550 °C. In the peri-Tyrrhenian zone and the Ligurian Sea, MLBD is below the Moho, which ranges from 17 to 20 km depth, and it has a temperature matching approximately to the Curie temperature of magnetite (580 °C).  相似文献   

12.
Topography for four areas in the Palouse region of southeastern Washington State having different patterns and encompassing areas of about 900 ha each were quantitatively compared and described using two-dimensional semi-variograms and periodograms. The four areas studied were from the Garfield, La Crosse, Thornton, and Wilcox quadrangle topographic maps. Semivariance of elevation residuals were modelled using a combination of spherical, periodic, or linear semivariogram models. The range of the spherical component was interpreted as a relatively short-range scale of correlation which was not periodic. For each of the study areas a model was developed to describe the variation in range with orientation. Values for the range from this model reached maximum values of from about 700 m to 800 m at an orientation of from 35° to 55° (approximately northeast) in each study area. This orientation was interpreted as the dominant direction of non-periodic small-scale landscape features. The wavelength and amplitude of the periodic semivariogram component, which were highly correlated, were interpreted in terms of parallel northeast-trending ridges having relatively long scales of periodic correlation varying in size from about 1350 m to 2100 m. This attempt to identify the dominant orientation of periodic landscape features using models for the wavelength and amplitude was, however, not completely definitive. Two-dimensional spectral analysis provided significantly more detail concerning orientation and wavelengths of the periodic topographic patterns than the semivariogram analysis. In the Garfield study area, spectral analysis identified north-trending ridge systems separated by a wavelength of 1494 m and northeast-trending systems with a wavelength of 747 m. In the La Crosse study area, both north and northeast-trending patterns were identified having periodic spacings of 980 and 735 m. North-trending ridges separated by wavelengths of 996 m and northeast-trending ridges separated by wavelengths of 747 or 996 m were the predominant periodic features of topography in the Thornton study area. In the Wilcox study area, northeast-trending ridge systems separated by wavelengths of 373, 498, or 996 m were detected. A comparison of the results from geostatistical and spectral analysis of these complex topographic surfaces shows that each approach had significant strengths and weaknesses. Two-dimensional analysis with semivariograms was the only method which could be used for identifying the correlation scale and orientation of relatively small non-periodic landscape features. Two-dimensional spectral analysis accurately identified the predominant orientation of relatively large periodic features in topography, whereas semivariogram analysis was somewhat inconclusive. Also, semivariograms were generally unable to detect the presence of multiple or harmonic periodicities operating at different wavelengths along a given orientation.  相似文献   

13.
阿坝州水库地震危险性分析   总被引:1,自引:0,他引:1  
阿坝州地处四川省西北部,青藏高原东南缘,岷江和黄河的源头都在其境内,素有“天府之国水塔“的美誉。本文根据阿坝州水资源、水库及其分布情况,结合该区的水库地震地质背景和区域的时空强地震活动特征,对阿坝州水库地震的危险性进行了分析,对未来诱发地震的可能性进行了预测有利于日常的监测和预报。  相似文献   

14.
重力位谱分析及重力异常导数换算新方法——余弦变换   总被引:17,自引:4,他引:17  
为了提高重力异常导数换算的精度,真实有效地反映地质体的异常特征,提出用余弦变换计算异常导数的新方法. 给出并证明了两个定理,利用它们推导出重力位余弦谱一般表达式以及重力异常各阶导数计算公式,建立了位场余弦谱分析理论. 模型实验中发现,用Fourier变换计算的一阶导数与理论导数偏差很大,而余弦变换计算的导数与理论异常导数拟合效果非常好,除边界几个数据因重力异常的有限截断产生的吉布斯效应残留使误差较大外,数据的计算精度均很高,误差为-0.09%~5%.  相似文献   

15.
通过求解引力相等原则下的Fredholm积分方程,可以得到不规则单一密度界面(Moho面)的起伏.本文充分参考了前人的理论研究,推导出扰动垂直重力梯度确定Moho面深度的频谱域表达式,该式具有二次项迭代精度.运用此公式进行了全球Moho面的恢复计算,并将该结果与CRUST1.0模型和GEMMA Moho模型进行了对比和验证.  相似文献   

16.
鄱阳湖氮磷营养盐变化特征及潜在性富营养化评价   总被引:3,自引:3,他引:3  
根据2008-10至2009-07之间4次的记录资料,阐述了鄱阳湖区氮磷营养盐的时间以及空间变化特征,并对硝氮、氨氮、磷酸盐和pH进行了相关分析,对鄱阳湖区进行了潜在性富营养化评价.结果表明:该湖区氮磷营养盐随时间和空间的不同呈现不同的变化规律,湖区水质受河流径流以及浮游植物的影响较大.在时间分布上表现出4月份的N/P比值最小,说明该季节正是浮游植物生长和繁殖最主要时期.在空间分布上表现出鄱阳湖的上游污染物浓度远小于下游污染值,湖区向出湖口浓度有增高趋势.N/P值从10月份的7.8上升至1月份的31.2,随后下降到4月份的7.4,在7月份又上升至8.9.氮磷营养盐和pH表现出不同的相关关系,如在4月份无机氮和pH的相关系数达0.5.综合各项因子的分析可以得出,潜在性富营养化评价结果是鄱阳湖在调查期间为磷污染比较严重.  相似文献   

17.
井-地与井间电位技术联合数值模拟研究剩余油分布(英文)   总被引:3,自引:2,他引:3  
电法测井有很高的分辨率,但是它的探测半径仅限于井孔周围;井-地电位技术虽然可以探测到足够大的范围,但是它的分辨率却受到很大的限制,特别是对于油水分布或者结构复杂的储层。本文试图通过井-地电位技术和井间电位技术的联合来研究地下储层油水分布范围。具体方法是,采用井-地电位技术研究油水分布在在横向上的展布情况,利用井间电位技术研究油水储层在垂向上的分布,然后采用井间电位结果标定井地电位结果,两者结合提高纵向分辨率,从而确定剩余油的三维空间分布。研究中通过研究注水初期数值模拟结果与水淹期数值模拟结果之差,求取剩余油分布范围。有限差分方法数值模拟表明:井-地电位技术与井间电位技术联合方法可以有效地确定剩余油分布。  相似文献   

18.
Regional seismic risk assessments and quantification of portfolio losses often require simulation of spatially distributed ground motions at multiple intensity measures. For a given earthquake, distributed ground motions are characterized by spatial correlation and correlation between different intensity measures, known as cross‐correlation. This study proposes a new spatial cross‐correlation model for within‐event spectral acceleration residuals that uses a combination of principal component analysis (PCA) and geostatistics. Records from 45 earthquakes are used to investigate earthquake‐to‐earthquake trends in application of PCA to spectral acceleration residuals. Based on the findings, PCA is used to determine coefficients that linearly transform cross‐correlated residuals to independent principal components. Nested semivariogram models are then fit to empirical semivariograms to quantify the spatial correlation of principal components. The resultant PCA spatial cross‐correlation model is shown to be accurate and computationally efficient. A step‐by‐step procedure and an example are presented to illustrate the use of the predictive model for rapid simulation of spatially cross‐correlated spectral accelerations at multiple periods.  相似文献   

19.
基于独立分量分析的多次波自适应相减技术   总被引:22,自引:7,他引:22       下载免费PDF全文
针对多次波自适应相减这个关键问题,文中首次提出利用独立分量分析技术来实现多次波和一次波的分离(简称ICAAMS). 现有的多次波自适应相减技术大都是采用输出信号(一次波)能量最小准则,基于二阶统计量的技术. 本文提出的ICAAMS采用了输出信号非高斯性最大准则,并利用高阶统计量来表征非高斯性. 简单的褶积模型和复杂的有限差分模型资料处理结果表明, 本文提出的方法可以有效地分离一次波和多次波.  相似文献   

20.
Spatial distribution of sources of strong and large earthquakes on the Xiaojiang fault zone in eastern Yunnan is studied according to historical earthquake data. 7 segments of relatively independent sources or basic units of rupture along the fault zone have been identified preliminarily. On every segment, time intervals between main historical earthquakes are generally characterized by “time-predictable” recurrence behavior with indetermination. A statistic model for the time intervals between earthquakes of the fault zone has been preliminarily established. And a mathematical method has been introduced into this paper to reckon average recurrence interval between earthquakes under the condition of having known the size of the last event at a specific segment. Based on these, ranges of the average recurrence intervals given confidence have been estimated for events of various sizes on the fault zone. Further, the author puts forward a real-time probabilistic model that is suitable to analyze seismic potential for individual segments along a fault zone on which earthquake recurrence intervals have been characterized by quasi-time-predictable behavior, and applies this model to calculate conditional probabilities and probability gains of earthquake recurring on the individual segments of the Xiaojiang fault zone during the period from 1991 to 2005. As a consequence, it has shown that two parts of this fault zone, from south of Dongchuan to Songming and from Chengjiang to Huaning, have relatively high likelihoods for strong or large earthquake recurring in the future. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 322–330, 1993.  相似文献   

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