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深水地震资料联合去多次波技术——以南海北部荔湾深水气田为例 被引量:5
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作者 张振波 谢涛 《天然气工业》 EI CAS CSCD 北大核心 2014年第5期37-42,共6页
珠江口盆地荔湾地区为南海北部深水油气重要勘探区。该区地震资料上多次波异常发育且复杂多样,单一的多次波压制方法有着明显的局限性。为此,在调查荔湾地区多次波特点的基础上,针对性地采取了多项技术组合应用的联合去多次波技术:①海... 珠江口盆地荔湾地区为南海北部深水油气重要勘探区。该区地震资料上多次波异常发育且复杂多样,单一的多次波压制方法有着明显的局限性。为此,在调查荔湾地区多次波特点的基础上,针对性地采取了多项技术组合应用的联合去多次波技术:①海底相关多次波为地震资料处理中多次波衰减的主要对象,可用基于波动方程的3DSRME技术来压制,理论和实际应用均表明3DSRME较之2DSRME更具技术优势;②拉冬域去多次波技术处理流程位于3DSRME之后,主要压制海底相关多次波以外的长周期多次波;③对于剩余的绕射多次波主要利用AVO预测法压制,基本思想是分离多次波与有效波,利用多次波与有效波的频率和能量差异进行压制。最后,从压制多次波效果和保幅性两个方面对联合去多次波技术进行了评价,认为该技术多次波压制效果明显,能够做到相对保幅处理。该技术为荔湾深水气田群的地震资料精细解释、AVO分析和叠前反演提供了优质的基础数据。 展开更多
关键词 荔湾深水气田 联合去多次 3D SRME技术 域去多次 绕射多次衰减技术 应用
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浅议民族民间音乐市场化进程中的变与不变——由佤族民歌《麻梨花开幸福来》改编为《黑珍珠》之所想
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作者 陈桂波 李思华 《文教资料》 2011年第17期71-72,共2页
佤族民歌《波央贝腊嗲腊冬》唱出了佤族人民对生活的热爱,对自然的崇拜;经过包装后变为《黑珍珠》,却成了一首爱情悲歌。经典的民族艺术被市场化改得面目全非。作者以此展开论述,认为在市场化的过程中,民族艺术必须保留其精华,才能取得... 佤族民歌《波央贝腊嗲腊冬》唱出了佤族人民对生活的热爱,对自然的崇拜;经过包装后变为《黑珍珠》,却成了一首爱情悲歌。经典的民族艺术被市场化改得面目全非。作者以此展开论述,认为在市场化的过程中,民族艺术必须保留其精华,才能取得成功。 展开更多
关键词 佤族民歌《央贝腊嗲腊 《黑珍珠》 民族民间音乐 不变
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A Theoretical Explanation of Anomalous Atmospheric Circulation Associated with ENSO Modoki during Boreal Winter 被引量:2
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作者 XING Nan LI Jian-Ping LI Yao-Kun 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第4期352-357,共6页
Based on a linear model, the present study provides analytical solutions for ideal triple forcing sources similar to sea surface temperature anomaly (SSTA) pat- terns associated with El Nino-Southern Oscillation (E... Based on a linear model, the present study provides analytical solutions for ideal triple forcing sources similar to sea surface temperature anomaly (SSTA) pat- terns associated with El Nino-Southern Oscillation (ENSO) Modoki in winter. The ideal triple pattern is composed of an equatorially symmetric heat source in the middle and equatoriaUy asymmetric cold forcing in the southeast and northwest. The equatorially symmetric heat source excites low-level cyclonic circulation anomalies associated with Rossby waves in both hemispheres, while the northwest- ern and southeastern equatorially asymmetric cold sources induce low-level anomalous anticyclones associated with Rossby waves in the hemisphere where the forcing source is located. Low-level zonal winds converge toward the heat sources associated with Kelvin and Rossby waves. Due to unequal forcing intensity in the northwest and southeast, atmospheric responses around the equatorially symmetric forcing become asymmetric, and low-level cyclonic circulation anomalies in the Southern Hemisphere become greater than those in the Northern Hemisphere. Ascending (descending) flows coincide with heat (cold) sources, resulting in a double-cell structure over the regions of forcing sources. Ideal triple patterns similar to SSTA patterns associated with La Nina Modoki produce opposite atmospheric responses. The theoretical atmospheric responses are consistent with observed circulation anomalies associated with ENSO Modoki. Therefore, the theoretical solutions can explain the dynamics responsible for atmospheric circulation anomalies associated with ENSO Modoki events. 展开更多
关键词 external forcing sources atmospheric responses ENSO Modoki
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Microwave-assisted Synthesis of Modified Polyaspartic Acid in Solvent 被引量:6
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作者 张玉玲 黄君礼 +1 位作者 程志辉 杨士林 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期458-462,共5页
Polyaspartic acid(PASP)is suitable for the inhibition of scale deposition from water.To enhance its in- hibition efficiency,PASP was modified by reacting aspartic acid(Asp)with glutamic acid(Glu)to provide Asp-Glu cop... Polyaspartic acid(PASP)is suitable for the inhibition of scale deposition from water.To enhance its in- hibition efficiency,PASP was modified by reacting aspartic acid(Asp)with glutamic acid(Glu)to provide Asp-Glu copolymer under microwave irradiation.The influence of reaction parameters on conversion,molecular weight and inhibition of CaCO3 precipitation was investigated Infra-red.(IR), 1H nuclear magnetic resonance( 1H NMR)and 13C nuclear magnetic resonance( 13C NMR)spectroscopies were used to characterize the copolymer.The results show that copolymerization of aspartic acid and glutamic acid is catalyzed by a small amount of phosphorous acid (H3PO4)in solvent,the product conversion is 98.05%under the following conditions:the molar ratio of glutamic acid to reactant[Glu/(Asp+Glu)]is 0.3 and that of catalyst(Cat)to reactant[Cat/(Glu+Asp)]is 0.05(0.65ml H3PO4),the volume of solvent dimethylformamide is 16ml,the microwave power used is 720W and the reaction for 3 min.The weight average molecular weight of copolymer synthesized under these conditions is 2709 and the inhi- bition rate for CaCO3 is 97.75%. 展开更多
关键词 microwave irradiation aspartic acid glutamic acid COPOLYMER conversion ratio scale inhibition
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Stationary Wave Activity Associated with the East Asian Winter Monsoon Pathway 被引量:1
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作者 WANG Lin 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第1期7-10,共4页
The pathway of the East Asian winter monsoon(EAWM) that usually leads to the out-of-phase pattern of surface air temperature between northern and southern East Asia is an important feature in the variability of the EA... The pathway of the East Asian winter monsoon(EAWM) that usually leads to the out-of-phase pattern of surface air temperature between northern and southern East Asia is an important feature in the variability of the EAWM besides its strength.Using the European Centre for Medium-Range Weather Forecasts 40-year(ERA40) reanalysis dataset,this study investigates the pathway-related stationary wave activity to explore the mechanism of the interannual variations in the EAWM pathway.It reveals that when the southern pathway of the EAWM is strong,the phase of the climatological stationary wave tends to be shifted westward significantly in both the horizontal and vertical directions by an anomalous wavenumber 2 pattern at mid-latitudes,whereas the changes are relatively small in the subtropics.The horizontal changes in the stationary wave phase facilitate a north-south-oriented East Asian trough in the middle troposphere that eventually produces the strong southern pathway of the EAWM.The vertical changes in the stationary wave,in contrast,feature a westward-tilted phase line with height over the North Pacific,indicating enhanced upward propagation of waves into the stratosphere.This result suggests that the phase of stationary waves at mid-latitudes dominate the interannual variations in the EAWM pathway.Moreover,it supports our previous interpretation of the possible role of the North Pacific sea surface temperature(SST) in the EAWM pathway variability.It also implies that the excitation of anomalous mid-latitude stationary waves may be the key in the response of the EAWM pathway to the North Pacific SST. 展开更多
关键词 East Asian winter monsoon PATHWAY stationary wave PHASE
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Object-based Classification of Baltic Sea Ice Extent and Concentration in Winter 2011 被引量:2
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作者 Aleksandra Mazur Adam Krezel 《Journal of Earth Science and Engineering》 2012年第8期488-495,共8页
The Baltic Sea is a brackish, mediterranean sea located in the middle latitudes of Europe. It is seasonally covered with ice. The ice covered areas during a typical winter are the Bothnian Bay, the Gulf of Finnland an... The Baltic Sea is a brackish, mediterranean sea located in the middle latitudes of Europe. It is seasonally covered with ice. The ice covered areas during a typical winter are the Bothnian Bay, the Gulf of Finnland and the Gulf of Riga. Sea ice plays an important role in dynamic and thermodynamic processes and also has a strong impact on the heat budget of the sea. Also a large part of transport goes by sea, and there is a need to create ice charts to make the marine transport safe. Because of high cloudiness in winter season and small amount of light in the northern part of the Baltic Sea, radar data are the most important remote sensing source of sea ice information. The main goal of the following studies is classification of the Baltic sea ice cover using radar data. The ENVISAT ASAR (Advanced Synthetic Aperture Radar) acquires data in five different modes. In the following studies ASAR Wide Swath Mode data were used. The Wide Swath Mode, using the ScanSAR technique provides medium resolution images (150 m) over a swath of 405 kin, at HH or VV polarization. In following work data from February 13th, February 24th and April 6th, 2011, representing three different sea ice situations were chosen. OBIA (object-based image analysis) methods and texture parameters were used to create sea ice extent and sea ice concentration charts. Based on object-based methods, it can separate single sea ice floes within the ice pack and calculate more accurately sea ice concentration. 展开更多
关键词 Baltic Sea sea ice ENVISAT ASAR object-based image analysis.
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Harmfulness of Leaf Miners (Agromyzidae) on Winter Wheat Plantations in Poland
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作者 Kamila Roik Felicyta Walczak 《Journal of Agricultural Science and Technology(A)》 2012年第3期417-422,共6页
The aim of the study was to determine the harmfulness of leaf miners and their species composition on winter wheat for the improvement of methods to control them. In order to determine the dates of the treatments, it ... The aim of the study was to determine the harmfulness of leaf miners and their species composition on winter wheat for the improvement of methods to control them. In order to determine the dates of the treatments, it was necessary to catch adult flies. The researchers used yellow 25 x 40 cm sticky traps placed on three control plots to catch the adults. Monitoring of cereal leaf miners flights in winter wheat was carried out in Babor6wko (greater Poland voivodeship). Yellow traps were placed above the tops of wheat during vegetation period. The number of damaged wheat stems was recorded. Fluctuations in weather conditions during the research affected the dynamics of leaf miner flies considerably. The maximum flights of leaf miner flies on winter wheat crops in years of the studies took place in May. The dynamics of leaf miners flights were different in growing season 2008 and 2009. The most common species were: Chromatomyia nigra (Ztt.), Chromatomyia fuscula (Ztt.) and Poemyza superciliosa (Ztt.). It was also discovered that the species composition of Agromyzidae damaging the winter wheat, changes in particular years. The results differ from the results of the previous research, which the dominant species were Phytomyza nigra (Mg.) and Agromyza ambiqua (FII.). 展开更多
关键词 Leaf miners AGROMYZIDAE winter wheat MONITORING yellow traps.
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FEATURE EXTRACTION AND RECOGNITION FOR ECHOES OF HRR RADAR
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作者 Xie Deguang Zhang Xianda 《Journal of Electronics(China)》 2009年第6期788-793,共6页
This paper describes a novel target recognition scheme using High Range Resolution (HRR) radar signatures. AutoRegressive (AR) method is used to extract features from HRR radar echoes based on scattering center model ... This paper describes a novel target recognition scheme using High Range Resolution (HRR) radar signatures. AutoRegressive (AR) method is used to extract features from HRR radar echoes based on scattering center model of target. The optimal linear transformation based on Euclidian distribution distance criterion is performed on AR model parameter vectors to reduce dimension of feature vectors further and improve the class discrimination capability of feature vectors. The optimization algorithm is designed utilizing the quadratic property of criterion function and Gaussian kernel based Parzen window density function estimator. The concept of Stochastic Information Gradient (SIG) is incorporated into the gradient of cost function to decrease the computational complexity of the algorithm. Simulation results using three real airplanes,data show the effectiveness of the proposed method. 展开更多
关键词 Radar target recognition Feature extraction AutoregRessive (AR) model Densityfunction estimation Stochastic Information Gradient (SIG)
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Possible linkage between winter extreme low temperature events over China and synoptic-scale transient wave activity 被引量:11
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作者 CHEN HaiShan LIU Lei ZHU YueJia 《Science China Earth Sciences》 SCIE EI CAS 2013年第7期1266-1280,共15页
Based on NECP/NCAR reanalysis data and daily temperature data of 743 stations in China, possible causes of winter extreme low temperature events are explored from the perspective of the synoptic-scale transient wave (... Based on NECP/NCAR reanalysis data and daily temperature data of 743 stations in China, possible causes of winter extreme low temperature events are explored from the perspective of the synoptic-scale transient wave (STW) activity. Results suggest that there is a close linkage between STW activity and extreme low temperature events. Firstly, case studies are carried out on the years with the most and least frequent extreme low temperature events. In the winter of 1967, two strong and stable STW trains were maintained over the Eurasian continent, and the strong westerly jet provided a good channel for the propagation of STW. Located in the downstream area of those two STW trains, China was significantly influenced by them and experienced frequent extreme low temperature events. Further analysis suggest that the intensity of the upstream transient wave and the areas where the transient waves reached are completely consistent with the intensity of extreme low temperature and the areas where frequent extreme low temperature event happened, respectively. In contrast, Westerly jet in 2006 was weaker and the path of transient wave propagation was shorter and weaker, resulting in the low frequency of extreme temperature. Secondly, in their long term variations, westerly jet is also consistent with the extreme low temperature frequency. The transient wave path changed before and after the 1980s. Further investigation suggests that transient wave intensities in key areas exhibit in-phase changes with the frequency of extreme low temperature events in the periods of 1959-1979 and 1986-2006. Meanwhile, the main features of transient wave activities in high-frequent years and low-frequent years of extreme low temperature events are similar to those of 1967 and 2006, respectively. Results indicate that winter extreme low temperature events in China have a very close relationship with the transient wave activity, implying the propagation and activity of STW are important factors affecting the winter extreme low temperature events in China. This study can also provide a new clue for better understanding the mechanisms of the extreme temperature events. 展开更多
关键词 extreme low temperature synoptic scale transient wave activity westerly jet
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