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几种基于最大互信息准则的联合均衡方法性能比较

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通信学报 2003年第5期24卷 146-152页

作者：刘郁林景晓军谭刚兵彭启琮重庆通信学院重庆400035 北京邮电大学智能信息研究所北京100876 国防大学研究生院北京100091 电子科技大学通信与信息工程学院四川成都610054

在块传输系统中,采用预编码-后均衡相结合的联合均衡技术能够有效克服信道的色散效应。本文针对无线信道中三种用滤波器组实现的块传输系统的联合均衡方法,就系统的最大互信息量和误码率性能作了分析比较。理论分析和仿真结果表明,作者... 详细信息

在块传输系统中,采用预编码-后均衡相结合的联合均衡技术能够有效克服信道的色散效应。本文针对无线信道中三种用滤波器组实现的块传输系统的联合均衡方法,就系统的最大互信息量和误码率性能作了分析比较。理论分析和仿真结果表明,作者提出的MMI-DFE1方法具有最佳性能。

关键词：最大互信息准则联合均衡块传输系统无线信道滤波器组 MM-DFEl方法误码率色散效应

The surface geochemical exploration of oil and gas in the Gangbatong-Ya'anxiang and the Dongqiao-Nam Co of the Qinghai-Tibet region

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Science China Earth Sciences 2009年第S1期52卷 69-76页

作者： XIONG Bo1,2,LI XianQing3,4.LI YiBin5 & TAN Qing6 1 Department of Geochemistry,Yangtze university,Jingzhou 4.4.23,China 2 Key Laboratory of exploration Technologies for Oil and Gas Resources(Yangtze university) ,Ministry of Education,Jingzhou 4.4.23,China 3 State Key Laboratory of Coal Resources and Safe Mining,China university of Mining and Technology,{4. 100083,China 4.Department of Resources and Earth Sciences,school of Resources and Safety Engineering,China university of Mining and Technology,{4. 100083,China 5 Institute of geosciences,Yangtze university,Jingzhou 4.4.23,China 6 Jinzhou Research Branch of New Region exploration,Research Institute of Petroleum exploration and Development,SINOPEC,Jingzhou 4.4.00,China 1. Department of Geochemistry Yangtze University Jingzhou 434023 China 2. Key Laboratory of exploration Technologies for Oil and Gas Resources (Yangtze university) Ministry of Education Jingzhou 434023 China 3. State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Beijing 100083 China 4. Department of Resources and Earth Sciences School of Resources and Safety Engineering China University of Mining and Technology Beijing 100083 China 5. Institute of geosciences Yangtze University Jingzhou 434023 China 6. Jinzhou Research Branch of New Region exploration Research Institute of Petroleum Exploration and Development SINOPEC Jingzhou 434100 China

Due to the complexity of geological background and the adverseness of natural geographical environment in the Qinghai-Tibet Plateau,it is very difficult to carry out petroleum geological study in this region. The Qinghai-Tibet Plateau is the only blank space of petroleum exploration on a large scale. The authors carried out the surface geochemical exploration of oil and gas in the Gangbatong-Ya'anxiang and Dongqiao-Nam Co of the Qinghai-Tibet region. Based on the data of actual detection and experiments in the studied area,the characteristics of concentration and profile distribution of the main geochemical exploration indicators(total adsorbed hydrocarbon,altered carbonate,thermal released mercury,etc.) were discussed. The origin of hydrocarbon was also discussed. Moreover,the oil and gas potential of different sections in the Qiangtang Basin and the Biru Basin were evaluated,which could provide references for the exploration and prediction of oil and gas in this region. The concentrations of total adsorbed hydrocarbons in the Ya'anxiang of Suoxian County-Zadong of Baqing County and the Jiecha-Dangxiong of Anduo County in the Qinghai-Tibet region are high,averaging 312.64.μL·kg-1 and 164.36 μL·kg-1. Their altered carbonate concentrations are relatively low,averaging 0.11% and 0.56%. Their concentrations of thermal released mercury are relatively high,averaging 13.09×10-9 and 1.94.10-9. Geochemical exploration results in fact reflect hydrocarbon information in the underground,which are mainly petroleum associated gas and over-matured cracking gas. The Jiecha-Charenluma and the Xiamaya'ertong-Suoba sections in the Qiangtang Basin are the most favorable ones for oil and gas and the Ekou-Zadong section is relatively favorable one,while the Nam Co and the Zigetangcuo-Dongqiao sections in the Biru Basin are the favorable ones for oil and gas,and the Jiang Co-Nading Co and the Ya'anxiang-Ya'ertong sections are relatively favorable ones.

关键词： geochemical exploration adsorbed hydrocarbon indicator hydrocarbon anomaly evaluation of oil and gas Qinghai-Tibet region

DNA barcoding provides distinction between Radix Astragali and its adulterants

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Science China(Life Sciences) 2010年第8期53卷 992-999页

作者： GUO HaiYan1,2, WANG WeiWei2, YANG Ning2, GUO BaoLin3, ZHANG Sun2, YANG RuiJing2, YUAN Ye2, YU JunLin4. HU SongNian2, SUN QiShi1 & YU Jun2 1school of Traditional Chinese Materia Medica, Shenyang Pharmaceutical university, Shenyang 110016, China 2Key Laboratory of Genome Sciences and information, beijing Institute of Genomics, Chinese Academy of Sciences, beijing 101300, China 3Chinese Academy of Medical Sciences, Peking Union Medical College Institute of Medicinal Plant Development, beijing 100094. China 4.epartment of Chemistry, Tonghua Normal College, Tonghua 134.02, China 1. school of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China2. Key Laboratory of Genome Sciences and Information Beijing Institute of Genomics Chinese Academy of Sciences Beijing 101300 China3. Peking Union Medical College Institute of Medicinal Plant Development Chinese Academy of Medical Sciences Beijing 100094 China4. Department of Chemistry Tonghua Normal College Tonghua 134002 China

Based on variable nuclear and/or organellar DNA sequences among vastly divergent species as well as morphologically indistinguishable species, DNA barcoding is widely applicable in species identification, biodiversity studies, forensic analyses, and authentication of medicinal plants. The roots of Astragalus membranaceus and A. membranaceus var. mongholica are commonly used as Radix Astragali in several Asian countries, including China, Japan, and Korea. However, in addition to the two species recorded in the Chinese Pharmacopoeia, there are twenty-three species from different genera including Astragalus, Oxytropis, Hedysarum, and Glycyrrhiza, which have been used as adulterants not only in trading markets but also by the herbal medicine industry. Therefore, a simple, reliable, and accurate classification method is important for distinguishing authentic Radix Astragali from its adulterants. In this study, we acquired data for 37 samples from four related genera within the family Fabaceae. Then we compared four candidate DNA barcoding markers using ITS, matK, rbcL, and coxI sequences from nuclear, chloroplast, and mitochondrial genomes, all commonly used for plants to identify genetic variations among genera, intraspecies, and interspecies. We observed higher divergences among genera and interspecies for ITS, which have the average Kimura 2-parameter distances of 4.5% and 14.1%, respectively, whereas matK was found to have sufficient divergence at the intraspecific level. Moreover, two indels detected in the matK sequence are useful for PCR studies in distinguishing Radix Astragali from its adulterants. This study suggests that the combined barcoding regions of ITS and matK are superior barcodes for Radix Astragali and further studies should focus on evaluating the applicability and accuracy of such combined markers for a wide range of traditional Chinese herbs.

关键词： Radix Astragali DNA barcode Astragalus adulterant identification

Prediction of petroleum exploration risk and subterranean spatial distribution of hydrocarbon accumulations

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Petroleum Science 2011年第1期8卷 17-23页

作者： Xie Hongbing Guo Qiulin Li Feng Li Jianzhong Wu Na Hu Suyun Liang Kun school of Energy Resources China University of GeosciencesBeijing 100083China Research Institute of Petroleum exploration ＆ Development PetroChinaBeijing 100083China Science ＆ Technology Management Department China National Petroleum CorporationBeijing 100007China

Investigation of spatial distribution of oil and gas resource and accurate prediction of the geographic location of its undiscovered resource is significant for reducing exploration risk and improving exploration benefit.A new method for predicting spatial distribution of oil resource is discussed in this *** consists of prediction of risk probability in petroleum exploration and simulation of hydrocarbon abundance. exploration risk probability is predicted by multivariate statistics,fuzzy mathematics and {4. processing techniques.A spatial attribute database for sample wells was set up and the Mahalanobis distance and Fuzzy value of given samples were ***,the Bayesian formula was used to calculate the hydrocarbon-bearing probability at the area of exploration ***,a hydrocarbon probability template is formed and used to forecast the probability of the unknown area. The hydrocarbon abundance is simulated based on Fourier integrals,frequency spectrum synthesis and fractal ***,the fast Fourier transformation（FFT） is used to transform the known hydrocarbon abundance from the spatial domain to the frequency domain,then,frequency spectrum synthesis is used to produce the fractal frequency spectrum,and FFT is applied to get the phase {4. of hydrocarbon-bearing ***,the frequency spectrum simulation is used to calculate the renewed hydrocarbon abundance in the play. This method is used to predict the abundance and possible locations of the undiscovered petroleum accumulations in the Nanpu Sag of the Bohai Bay Basin,*** prediction results for the well-explored onshore area of the northern Nanpu Sag agree well with the actual *** the less-explored offshore areas in the southern Nanpu Sag,the prediction results suggest high hydrocarbon abundance in Nanpu-1 and Nanpu-2,providing a useful guiding for future exploration.

关键词： Hydrocarbon resources abundance risk forecast Nanpu sag frequency spectrum simulation fractal theory

Spatial Distribution of Land Cover and Vegetation Activity along Topographic Gradient in an Arid River Valley, SW China

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Journal of Mountain Science 2009年第3期6卷 274-285页

作者： LIU Wen XU Xianli LUO Jiancheng SHEN Zhanfeng ZHONG Qiuhai Department of Automatic Control School of Automation Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Centre for Hydrology Micrometeorology and Climate Change Department of Civil and Environmental Engineering University College Cork Cork Ireland

Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern China. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing regions.

关键词： Vertical distribution of land cover Anthropogenic activity Vegetation activity Environmental variability China

Study on Fault Activity in Linnan Area of Huimin Depression,Bohai Bay Basin

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Study on Fault Activity in Linnan Area of Huimin Depression,...

河口坝、沿岸坝的形成及成藏机制——以松辽盆地西、南部沉积体系为例

2011 World Congress on Engineering and Technology(CET 2011)

作者： Zhou Hao-wei 1 Jiang Zai-xing 3 Kang Rong 4.school of Energy Resources China university of geosciences beijing China Wu Zhi-ping 2 Li Wei 5 school of geosciences China university of Petroleum Qingdao China

Based on the analysis of growth index,fault throw and fault activity rate,we find the method of fault activity rate integrates advantages of other methods which avoids the influence of erosion and could carry out comparison among fault activities of different geological *** optimize the method of fault activity rate to quantificationally analyze the characteristics of fault activities in Linnan area,Huimin depression and the results show:the main direction of the faults in Linnan area is nearly NEE-trending and most of the faults have two larger activity *** acts intensively in the period of Es2 and Ed and weakens in the period of Es1 and *** is a small comeback in the period of Nm at *** conduct the force analysis of this area based on stress ellipsoid and find that the stress state agrees well with the regional geological *** evolution of faults is impacted by the subduction of Pacific plate and the compression of Indian Ocean plate.

关键词： fault activity fault activity rate formation mechanism Linnan area Huimin depression

来源： cnki会议评论

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新疆石油地质 2004年第6期25卷 592-595页

作者：卫平生王建功潘树新王斌婷中国科学院海洋研究所中国石油石油勘探开发科学研究院西北分院

松辽盆地西、南部沉积体系中部含油组合(青山口组、姚家组)河口坝、沿岸坝较为发育,其单层厚度大、横向迁移分布面积广,由河口坝、沿岸坝形成的厚层底水油气藏是该高砂地比发育区的一种重要的岩性油气藏。从河口坝、沿岸坝的成因、分布... 详细信息

松辽盆地西、南部沉积体系中部含油组合(青山口组、姚家组)河口坝、沿岸坝较为发育,其单层厚度大、横向迁移分布面积广,由河口坝、沿岸坝形成的厚层底水油气藏是该高砂地比发育区的一种重要的岩性油气藏。从河口坝、沿岸坝的成因、分布以及内部结构研究入手,探讨了河口坝、沿岸坝与小断距断层和低幅度构造的成因关系,在分析了河口坝、沿岸坝含油气特征的基础上,探讨了其成藏机理、成藏主控因素以及分布规律,指出了勘探的有利目标区。

关键词：沉积体系河口成藏机制低幅度构造松辽盆地形成成藏机理底水油气藏岩性油气藏主控因素

Anisotropic characteristics of electrical responses of fractured reservoir with multiple sets of fractures

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Petroleum Science 2009年第2期6卷 127-138页

作者： Shen Jinsong Su Benyu Guo Naichuan Department of Geophysics School of Resource and Information Technology China University of Petroleum Beijing 102249 China Key Laboratory of CNPC Geophysical exploration China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China

In fractured reservoirs, the fractures not but also form the main flow channels which connect productivity of reservoirs. However, because of the only provide the storage space for hydrocarbons, the pores of the matrix, so fractures dominate the heterogeneity and randomness of the distribution of fractures, exploration and evaluation of fractured reservoirs is still one of the most difficult problems in the oil industry. In recent years, seismic anisotropy has been applied to the assessment of fractured formations, whereas electrical anisotropy which is more intense in fractured formations than seismic anisotropy has not been studied or used so extensively. In this study, fractured reservoir models which considered multiple sets of fractures with smooth and partly closed, rough surfaces were established based on the fractures and pore network, and the vertical and horizontal electrical resistivities were derived as a function of the matrix and fracture porosities according to Ohm＇s law. By using the anisotropic resistivity equations, variations of the electrical anisotropy of three types of fractured models under the conditions of free pressure and confining pressure were analyzed through the variations of the exerted pressure, matrix porosity, fracture aperture and formation water resistivity. The differences of the vertical and horizontal resistivities and the anisotropy between the connected and non-connected fractures were also analyzed. It is known from the simulated results that an increase of the confining pressure causes a decrease of electrical anisotropy because of the elasticity of the closed fractures and the decrease of the fracture aperture. For a fixed fracture porosity, the higher the matrix porosity, the weaker the electrical anisotropy in the rock formation.

关键词： Fractured reservoir partly closed fracture electrical anisotropy fracture roughness

An Evaluation of BeiDou Navigation Satellite System

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An Evaluation of BeiDou Navigation Satellite System