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Machine Learning Security Defense Algorithms Based on Metadata Correlation Features
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作者 Ruchun Jia Jianwei Zhang Yi Lin 《Computers, Materials & Continua》 SCIE EI 2024年第2期2391-2418,共28页
With the popularization of the Internet and the development of technology,cyber threats are increasing day by day.Threats such as malware,hacking,and data breaches have had a serious impact on cybersecurity.The networ... With the popularization of the Internet and the development of technology,cyber threats are increasing day by day.Threats such as malware,hacking,and data breaches have had a serious impact on cybersecurity.The network security environment in the era of big data presents the characteristics of large amounts of data,high diversity,and high real-time requirements.Traditional security defense methods and tools have been unable to cope with the complex and changing network security threats.This paper proposes a machine-learning security defense algorithm based on metadata association features.Emphasize control over unauthorized users through privacy,integrity,and availability.The user model is established and the mapping between the user model and the metadata of the data source is generated.By analyzing the user model and its corresponding mapping relationship,the query of the user model can be decomposed into the query of various heterogeneous data sources,and the integration of heterogeneous data sources based on the metadata association characteristics can be realized.Define and classify customer information,automatically identify and perceive sensitive data,build a behavior audit and analysis platform,analyze user behavior trajectories,and complete the construction of a machine learning customer information security defense system.The experimental results show that when the data volume is 5×103 bit,the data storage integrity of the proposed method is 92%.The data accuracy is 98%,and the success rate of data intrusion is only 2.6%.It can be concluded that the data storage method in this paper is safe,the data accuracy is always at a high level,and the data disaster recovery performance is good.This method can effectively resist data intrusion and has high air traffic control security.It can not only detect all viruses in user data storage,but also realize integrated virus processing,and further optimize the security defense effect of user big data. 展开更多
关键词 Data-oriented architecture METADATA correlation features machine learning security defense data source integration
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Numerical Simulation of the Settling Flux of Biodeposition in a Bay with Cage Culture Through Similarity Theory and a Simplified Pollution Source
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作者 LIU Yao CHEN Yifan GE Changzi 《Journal of Ocean University of China》 CAS CSCD 2024年第1期247-254,共8页
The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is ... The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is extremely important for determining the spatial distribution of biodeposition.Theoretically,biodeposition in cage culture areas without specific emission rules can be simplified as point source pollution.Fluent is a fluid simulation software that can simulate the dispersion of particulate matter simply and efficiently.Based on the simplification of pollution sources and bays,the settling flux of biodeposition can be easily and effectively simulated by Fluent fluid software.In the present work,the feasibility of this method was evaluated by simulation of the settling flux of biodeposition in Maniao Bay,Hainan Province,China,and 20 sampling sites were selected for determining the settling fluxes.At sampling sites P1,P2,P3,P4,P5,Z1,Z2,Z3,Z4,A1,A2,A3,A4,B1,B2,C1,C2,C3 and C4,the measured settling fluxes of biodeposition were 26.02,15.78,10.77,58.16,6.57,72.17,12.37,12.11,106.64,150.96,22.59,11.41,18.03,7.90,19.23,7.06,11.84,5.19 and 2.57 g d^(−1)m^(−2),respectively.The simulated settling fluxes of biodeposition at the corresponding sites were 16.03,23.98,8.87,46.90,4.52,104.77,16.03,8.35,180.83,213.06,39.10,17.47,20.98,9.78,23.25,7.84,15.90,6.06 and 1.65 g d^(−1)m^(−2),respectively.There was a positive correlation between the simulated settling fluxes and measured ones(R=0.94,P=2.22×10^(−9)<0.05),which implies that the spatial differentiation of biodeposition flux was well simulated.Moreover,the posterior difference ratio of the simulation was 0.38,and the small error probability was 0.94,which means that the simulated results reached an acceptable level from the perspective of relative error.Thus,if nonpoint source pollution is simplified to point source pollution and open waters are simplified based on similarity theory,the setting flux of biodeposition in the open waters can be simply and effectively simulated by the fluid simulation software Fluent. 展开更多
关键词 fluent fluid simulation software pollution source simplification posterior difference ratio similarity theory Spear-man correlation
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Oil-source rock correlation and quantitative assessment of Ordovician mixed oils in the Tazhong Uplift, Tarim Basin 被引量:10
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作者 Li Sumei Pang Xiongqi +2 位作者 Zhang Baoshou Xiao Zhongyao Gu Qiaoyuan 《Petroleum Science》 SCIE CAS CSCD 2010年第2期179-191,共13页
The origin of the marine oils in the Tarim Basin has long been a disputed topic. A total of 58 DST (drill stem test) crude oil and 8 rock samples were investigated using a comprehensive geochemical method to charact... The origin of the marine oils in the Tarim Basin has long been a disputed topic. A total of 58 DST (drill stem test) crude oil and 8 rock samples were investigated using a comprehensive geochemical method to characterize and identify the origin of the Ordovician oils in the Tazhong Uplift, Tarim Basin, northwest China. Detailed oil–oil and oil–source rock correlations show that the majority of the oils have typical biomarker characteristics of the Middle-Upper Ordovician (O2+3) source rock and the related crude oil. These characteristics include a distinct "V-shaped" relative abundance of C27, C28 and C29 regular steranes, low abundance of dinosterane, 24-norcholestanes, triaromatic dinosteroids and gammacerane. Only a few oils display typical biomarker characteristics indicating the Cambrian–Lower Ordovician (∈-O1) genetic affinity, such as linear or anti "L" shape distribution of C27, C28 and C29 regular sterane, with relatively high concentrations of dinosterane, 24-norcholestanes, triaromatic dinosteroids and gammacerane. It appears that most of the Ordovician oils in the Tazhong Uplift were derived from the O2+3 intervals, as suggested by previous studies. However, the compound specific n-alkane stable carbon isotope data indicate that the Ordovician oils are mixtures from both the ∈-O1 and O2+3 source rocks rather than from the O2+3 strata alone. It was calculated that the proportion of the∈-O1 genetic affinity oils mixed is about 10.8%-74.1%, with an increasing trend with increasing burial depth. This new oil-mixing model is critical for understanding hydrocarbon generation and accumulation mechanisms in the region, and may have important implications for further hydrocarbon exploration in the Tarim Basin. 展开更多
关键词 BIOMARKER compound specific isotope oil–source rock correlation mixed oil
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Effect of source size and emission time on the p–p momentum correlation function in the two-proton emission process 被引量:2
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作者 Long Zhou De-Qing Fang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第5期64-69,共6页
The effect of source size and emission time on the proton-proton(p-p)momentum correlation function(Cpp(q))has been studied systematically.Assuming a spherical Gaussian source with space and time profile according to t... The effect of source size and emission time on the proton-proton(p-p)momentum correlation function(Cpp(q))has been studied systematically.Assuming a spherical Gaussian source with space and time profile according to the function S(r,t)~exp(-r2/2 r02-t/τ)in the correlation function calculation code(CRAB),the results indicate that one Cpp(q)distribution corresponds to a unique combination of source size r0 and emission timeτ.Considering the possible nuclear deformation from a spherical nucleus,an ellipsoidal Gaussian source characterized by the deformation parameter∈=ΔR/R has been simulated.There is almost no difference of Cpp(q)between the results of spherically and ellipsoidally shaped sources with small deformation.These results indicate that a unique source size r0 and emission time could be extracted from the p-p momentum correlation function,which is especially important for identifying the mechanism of twoproton emission from proton-rich nuclei.Furthermore,considering the possible existence of cluster structures within a nucleus,the double Gaussian source is assumed.The results show that the p-p momentum correlation function for a source with or without cluster structures has large systematical differences with the variance of r0 andτ.This may provide a possible method for experimentally observing the cluster structures in proton-rich nuclei. 展开更多
关键词 Two-proton EMISSION p–p MOMENTUM correlation function source SIZE EMISSION time
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Effective source rock selection and oil–source correlation in the Western Slope of the northern Songliao Basin,China 被引量:2
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作者 He Bi Peng Li +2 位作者 Yun Jiang Jing-Jing Fan Xiao-Yue Chen 《Petroleum Science》 SCIE CAS CSCD 2021年第2期398-415,共18页
This study considers the Upper Cretaceous Qingshankou Formation,Yaojia Formation,and the first member of the Nenjiang Formation in the Western Slope of the northern Songliao Basin.Dark mudstone with high abundances of... This study considers the Upper Cretaceous Qingshankou Formation,Yaojia Formation,and the first member of the Nenjiang Formation in the Western Slope of the northern Songliao Basin.Dark mudstone with high abundances of organic matter of Gulong and Qijia sags are considered to be significant source rocks in the study area.To evaluate their development characteristics,differences and effectiveness,geochemical parameters are analyzed.One-dimensional basin modeling and hydrocarbon evolution are also applied to discuss the effectiveness of source rocks.Through the biomarker characteristics,the source–source,oil–oil,and oil–source correlations are assessed and the sources of crude oils in different rock units are determined.Based on the results,Gulong and Qijia source rocks have different organic matter primarily detrived from mixed sources and plankton,respectively.Gulong source rock has higher thermal evolution degree than Qijia source rock.The biomarker parameters of the source rocks are compared with 31 crude oil samples.The studied crude oils can be divided into two groups.The oil–source correlations show that group I oils from Qing II–III,Yao I,and Yao II–III members were probably derived from Gulong source rock and that only group II oils from Nen I member were derived from Qijia source rock. 展开更多
关键词 Songliao basin Western slope source rock distinction Crude oils BIOMARKER Oil-source correlation
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Effect of relaxation time on the squeezed correlations of bosons for evolving sources in relativistic heavy-ion collisions 被引量:1
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作者 Wei-Ning Zhang Peng-Zhi Xu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第2期87-92,共6页
The squeezed back-to-back correlation(SBBC)of a boson-antiboson pair is sensitive to the time distribution of the particle-emitting source,and the SBBC function for an evolving source is expected to be affected by the... The squeezed back-to-back correlation(SBBC)of a boson-antiboson pair is sensitive to the time distribution of the particle-emitting source,and the SBBC function for an evolving source is expected to be affected by the relaxation time of the system.In this study,we investigated the effect of relaxation time on the SBBC function.We propose a method for calculating the SBBC function with relaxation-time approximation for evolving sources.SBBC functions of D^(0)D^(-0)in relativistic heavy-ion collisions were investigated using a hydrodynamic model.We found that the relaxation time reduces the amplitudes of the SBBC functions.This becomes apparent for long relaxation times and large initial relative deviations of the chaotic and squeezed amplitudes from their equilibrium values in the temporal steps. 展开更多
关键词 Relaxation time Squeezed back-to-back correlation Evolving source Relativistic heavy-ion collisions
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The Occurrence of Oleananes in the Beibuwan Basin and Its Application to the Study of Maturity and Oil-Source Rock Correlation 被引量:9
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作者 LI Meijun WANG Tieguan +4 位作者 LIU Ju ZHANG Meizhu LU Hong MA Qinglin GAO Lihui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期585-595,共11页
The oleanane parameter, i.e., OP (oleananes/(oleananes+C30hopanes)) in the two sedimentary columns of the Beibuwan Basin, South China Sea, can be used to delimit the top of oil generation window, with Ro (/%) o... The oleanane parameter, i.e., OP (oleananes/(oleananes+C30hopanes)) in the two sedimentary columns of the Beibuwan Basin, South China Sea, can be used to delimit the top of oil generation window, with Ro (/%) of 0.53 in Well M1 and 0.55 in Wells H1/Hd1/Hd2, respectively. Comparing with vitrinite reflectance (Ro/%), the OP features a dynamic range and can indicate the oil generation window more precisely. By using OP and other geochemical indices, the oil-source correlation is also conducted. It suggests that the oils in wells M1 and M2 are derived from the source rocks in situ. The mudstone in Huachang uplift is not the main source rocks for oils in this area, The OP is also a useful oil-source correlation parameter in some Tertiary lacustrine basins. 展开更多
关键词 oleanane parameter (OP) BIOMARKER MATURITY oil-source correlation Fushan Depression
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Study on oil–source correlation by analyzing organic geochemistry characteristics: a case study of the Upper Triassic Yanchang Formation in the south of Ordos Basin, China 被引量:5
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作者 Delu Li Rongxi Li +6 位作者 Baoping Wang Zhi Liu Xiaoli Wu Futian Liu Bangsheng Zhao Jinghua Cheng Wenbin Kang 《Acta Geochimica》 EI CAS CSCD 2016年第4期408-420,共13页
In the south of the Ordos Basin, the oil source of the Upper Triassic Yanchang Formation is confused all the time, which affects further exploration. In this study, oil sources from the oil layers of Ch6, Ch8 and Ch9 ... In the south of the Ordos Basin, the oil source of the Upper Triassic Yanchang Formation is confused all the time, which affects further exploration. In this study, oil sources from the oil layers of Ch6, Ch8 and Ch9 are all analyzed and confirmed. Through their carbon isotope value and biomarkers, characteristics of crude oils from the Yanchang Formation are analyzed. Then, the oil–source relation is discussed, with the source rocks' features.Finally, the oil–source relation is calculated through cluster analysis. It is believed that the oils from the Yanchang Formation deposit in a similar redox environment, with weak oxidation–weak reduction, and have all entered maturity stage. Ch9 crude oil is more mature than crude oils from Ch6 and Ch8, and has more advanced plants and fewer algae. Gas chromatography(GC) and gas chromatography–mass spectrometry(GC–MS) analysis show that crude oils from Ch6 and Ch8 may come from Ch7, and Ch9 crude oil may not. Cluster analysis displays that crude oils from Ch6 and Ch8 have closer squared Euclidean distance with Ch7 source rocks than Ch9 crude oil does,indicating crude oils from Ch6 and Ch8 stem from Ch7 source rocks. And Ch9 crude oil has rather close squared Euclidean distance with Ch9 source rocks, illustrating Ch9 crude oil may be from Ch9 source rocks. This research may provide the theoretical basis for the next exploration deploy in the south of Ordos Basin. 展开更多
关键词 鄂尔多斯盆地南部 三叠系延长组 油源分析 有机地球化学 特征对比 气相色谱-质谱法 氧化还原环境 上三叠统延长组
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The geochemical characteristics and oil-source rock correlation of oilshow from the Majiashan profile, Chaoxian County, South of Anhui Province 被引量:4
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作者 TANG Youjun WEN Zhigang ZAN Ling 《Chinese Journal Of Geochemistry》 EI CAS 2008年第1期53-57,共5页
In the future time the exploration of marine oil and gas will be one of the significant domains in China. In this paper the biomarker assemblage characteristics of oilshow in the Nanlinghu Formation of the Majiashan p... In the future time the exploration of marine oil and gas will be one of the significant domains in China. In this paper the biomarker assemblage characteristics of oilshow in the Nanlinghu Formation of the Majiashan pro- file, which is located in Chaoxian County, south of Anhui Province, are described in the light of gas chromatogra- phy/mass spectrometric (GCMS) analysis on the qualitative and quantitative basis. Based on the investigation of the biomarker assemblage characteristics of possible source rocks developed in the area studied, a conclusion is drawn that the oilshow was generated from the Nanlinghu Formation source rocks (abbreviated as T1n), instead of the Qixia Formation source rocks (abbreviated as P1q). It is pointed out that the T1n is of strong potential for future oil explora- tion, and therefore much attention should be paid to it. 展开更多
关键词 地理特征 岩石 油-水系统 安徽省
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Explicit Correlation Model of Multi-source Constraints for Re-design Parts with Complex Curved Surface 被引量:2
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作者 JIA Zhenyuan WANG Fuji +1 位作者 WANG Yongqing GUO Dongming 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期385-391,共7页
In precision machining of complex curved surface parts with high performance, geometry accuracy is not the only constraint, but the performance should also be met. Performance of this kind of parts is closely related ... In precision machining of complex curved surface parts with high performance, geometry accuracy is not the only constraint, but the performance should also be met. Performance of this kind of parts is closely related to the geometrical and physical parameters, so the final actual size and shape are affected by multiple source constraints, such as geometry, physics, and performance. These parts are rather difficult to be manufactured and new manufacturing method according to performance requirement is urgently needed. Based on performance and manufacturing requirements for complex curved surface parts, a new classification method is proposed, which divided the complex curved surface parts into two categories: surface re-design complex curved surface parts with multi-source constraints(PRCS) and surface unique complex curved surface parts with pure geometric constraints(PUCS). A correlation model is constructed between the performance and multi-source constraints for PRCS, which reveals the correlation between the performance and multi-source constraints. A re-design method is also developed. Through solving the correlation model of the typical paws performance-associated surface, the mapping relation between the performance-associated surface and the related removal amount is obtained. The explicit correlation model and the method for the corresponding related removal amount of the performance-associated surface are built based on the classification of surface re-design complex curved surface parts with multi-source constraints. Research results have been used in the actual processing of the typical parts such as radome, common bottom components, nozzle, et al., which shows improved efficiency and accuracy of the precision machining for the surface re-design parts with complex curved surface. 展开更多
关键词 multi-source constraints surface re-design performance associated surface explicit correlation model
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Oil-source correlation of the pre-Tertiary in the Huanghua Depression:Insights from stable carbon isotopes and molecular markers 被引量:1
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作者 YANG Yongcai ZHANG Zhihuan +4 位作者 LI Wei QIN Liming FANG Chaohe LIN Yuxiang LIU Hua 《Chinese Journal Of Geochemistry》 EI CAS 2008年第3期265-275,共11页
Stable carbon isotopes were used together with molecular markers to constrain genetic relationships between sandstone extracts and potential source rocks in the pre-Tertiary in the Huanghua Depression,North China.Comp... Stable carbon isotopes were used together with molecular markers to constrain genetic relationships between sandstone extracts and potential source rocks in the pre-Tertiary in the Huanghua Depression,North China.Comparison of the extracts from Permo-Carboniferous terrigenous mudstones and Ordovician marine carbonates indicated that their prominent differences are in stable carbon isotopes,molecular markers and thermal maturity.Although the extracts of the Mesozoic and Lower Permian Xiashihezi Formation sandstones have some similar iso-topic characteristics,molecular markers data provide a good correlation between the Upper Jurassic-Lower Cretaceous oils and the Upper Carboniferous Taiyuan Formation mudstones,and between the Lower Permian Xiashihezi Formation oils and the Lower Permian mudstones.The results showed that the Upper Jurassic-Lower Cretaceous sandstone oils were derived chiefly from the Upper Carboniferous Taiyuan Formation terrigenous mudstones and that the Lower Permian Xiashihezi Formation oils were sourced from the Lower Permian Shanxi Formation and Xiashihezi Formation terrigenous mudstones. 展开更多
关键词 石油资源 中生代 洼地 奥淘纪
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Ruthenium-ion-catalyzed oxidation of asphaltenes and oil-source correlation of heavy oils from the Lunnan and Tahe oilfields in the Tarim Basin, NW China 被引量:1
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作者 马安来 张水昌 +3 位作者 张大江 金之钧 马晓娟 陈清棠 《Chinese Journal Of Geochemistry》 EI CAS 2005年第1期28-36,共9页
The identification of marine source rocks in the Tarim Basin is debated vigorously. The intention of this paper is to investigate the asphaltenes in heavy oils from the Lunnan and Tahe oilfields and Well TD2 with ruth... The identification of marine source rocks in the Tarim Basin is debated vigorously. The intention of this paper is to investigate the asphaltenes in heavy oils from the Lunnan and Tahe oilfields and Well TD2 with ruthenium-ions-catalyzed oxidation technique (RICO), in order to explore its role in oil-oil and oil-source correlations. The RICO products included n-alkanoic acids, α, ω-di-n-alkanoic acids, branched alkanoic acids, tricyclic terpanoic acids, hopanoic acids, gammacerane carboxylic acid , regular sterane carboxylic acids and 4-methylsterane carboxylic acids. The n-alkyl chains and biomarkers bounded on the asphaltenes were of unsusceptibility to biodegradation. The distribution and absolute concentrations of n-alkanoic acids in the RICO products of heavy oils from the Lunnan and Tahe oilfields are different from those of Well TD2. The biomarkers bounded on the asphaltenes, especially steranes, have a distribution trend similar to that of the counterparts in saturates. The sterane carboxylic acids and 4-methylsterane carboxylic acids in the RICO products of heavy oils from the Lunnan and Tahe oilfields, dominated by C-{30} sterane and C-{31} 4-methylsterane carboxylic acids, respectively, are significantly different from those of the heavy oils of Well TD2, whose dominating sterane and 4|methylsterane carboxylic acids are C-{28} sterane and C-{29} 4-methylsterane acids, respectively. The RICO products of the asphaltenes further indicate that the Middle-Upper Ordovician may be the main source rocks for heavy oils from the Lunnan and Tahe oilfields. 展开更多
关键词 钌-离子催化氧化 沥青 重油 塔里木盆地 油源作用
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Dibenzofuran Series in Terrestrial Source Rocks and Crude Oils and Applications to Oil-Source Rock Correlations in the Kuche Depression of Tarim Basin, NW China 被引量:9
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作者 李景贵 李梅 王兆云 《Chinese Journal Of Geochemistry》 EI CAS 2004年第2期113-123,共11页
Ten series of aromatic hydrocarbon compounds (biphenyl, naphthalene, phenanthrene, anthracene, retene, chrysene, benzoanthracene, dibenzofuran, fluorene, dibenzothiophene) isolated from seven Triassic and Jurassic lac... Ten series of aromatic hydrocarbon compounds (biphenyl, naphthalene, phenanthrene, anthracene, retene, chrysene, benzoanthracene, dibenzofuran, fluorene, dibenzothiophene) isolated from seven Triassic and Jurassic lacustrine mudstone samples and three swamp coal samples, as well as five crude oil samples collected in the Kuche depression of the Tarim Basin, NW China, have been analysed by GC-MS techniques. It is found that the relative abundances of dibenzofuran series are higher in the three swamp coal samples than those in the lacustrine mudstone samples. Based on the similar relative abundances of dibenzofuran series, especially dibenzofuran compound, in the TICs of aromatic hydrocarbons, crude oils from wells SA3 (K), YTK5 (E, K) and QL1 (E) are thought to have been derived predominantly from the coals of the Lower Jurassic Yangxia Formation or Middle Jurassic Kezilenuer Formation, whereas those from wells YM7 (O) and YH1 (E) were derived mainly from Triassic and Jurassic lacustrine mudstones in the Kuche depression. This is the first report about how to distinguish coal-generated oils from lacustrine mudstone-generated oils in the Kuche depression in terms of the dibenzofuran series. The present paper has enlightening and directive significance for further oil-source rock correlations and oil and/or gas exploration in the Kuche depression of the Tarim Basin. 展开更多
关键词 氧芴 芳烃 三叠纪 侏罗纪 泥岩 油源
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Multiparticle Bose Correlations of Bosons Emitted from Granular Source
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作者 D.Keane S.Y.Chu S.Y.Fung 《Chinese journal of nuclear physics》 1994年第3期195-198,共4页
The multiparticle Bose correlations of bosons emitted from dispersed thermaldroplets of quark-gluon plasma are simulated by Monte Carlo.It turns out that ana-lyses of multiparticle Bose correlations can detect the gra... The multiparticle Bose correlations of bosons emitted from dispersed thermaldroplets of quark-gluon plasma are simulated by Monte Carlo.It turns out that ana-lyses of multiparticle Bose correlations can detect the granularity of the emitting source,providing a signal of the existence of a mixed phase of quark-gluon plasma andhadronic gas in ultrarelativistic heavy ion collisions. 展开更多
关键词 Multiparticle BOSE correlationS source GRANULARITY Quark-gluon-plasma droplets Ultrarelativistic heavy ion collisions Monte Carlo simulation
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Oil-source correlation of Lower-Triassic oil seepages in Ni'erguan village, Southern Guizhou Depression, China
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作者 Fang Yuan Yuhong Liao +1 位作者 Yunxin Fang Ansong Geng 《Acta Geochimica》 EI CAS CSCD 2016年第1期50-63,共14页
There are abundant bitumens and oil seepages stored in vugs in a Lower-Triassic Daye formation(T_1d)marlite in Ni'erguan village in the Southern Guizhou Depression. However, the source of those oil seepages has no... There are abundant bitumens and oil seepages stored in vugs in a Lower-Triassic Daye formation(T_1d)marlite in Ni'erguan village in the Southern Guizhou Depression. However, the source of those oil seepages has not been determined to date. Multiple suites of source rocks of different ages exist in the depression. Both the oil seepages and potential source rocks have undergone complicated secondary alterations, which have added to the difficulty of an oil-source correlation. For example, the main source rock, a Lower-Cambrian Niutitang Formation"(∈_1n) mudstone, is over mature, and other potential source rocks, both from the Permian and the Triassic, are still in the oil window. In addition, the T_1d oil seepages underwent a large amount of biodegradation. To minimize the influence of biodegradation and thermal maturation, special methods were employed in this oil-source correlation study. These methods included catalytic hydropyrolysis, to release covalently bound biomarkers from the over mature"kerogen of ∈_1n mudstone, sequential extraction, to obtain chloroform bitumen A and chloroform bitumen C from the T_1d marlite, and anhydrous pyrolysis, to release pyrolysates from the kerogen of T_1d marlite. Using the methods above, the biomarkers and n-alkanes releasedfrom the oil samples and source rocks were analysed by GC–MS and GC-C-IRMS. The oil-source correlation indicated that the T_1d oil seepage primarily originated from"the ∈_1n mudstone and was partially mixed with oil generated from the T_1d marlite. Furthermore, the seepage also demonstrated that the above methods were effective for the complicated oil-source correlation in the Southern Guizhou Depression. 展开更多
关键词 三叠系 油苗 坳陷 贵州 气相色谱质谱分析 生物标志物 氯仿沥青A 油源对比
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AN NMF ALGORITHM FOR BLIND SEPARATION OF CONVOLUTIVE MIXED SOURCE SIGNALS WITH LEAST CORRELATION CONSTRAINS
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作者 Zhang Ye Fang Yong 《Journal of Electronics(China)》 2009年第4期557-563,共7页
Most of the existing algorithms for blind sources separation have a limitation that sources are statistically independent. However, in many practical applications, the source signals are non- negative and mutual stati... Most of the existing algorithms for blind sources separation have a limitation that sources are statistically independent. However, in many practical applications, the source signals are non- negative and mutual statistically dependent signals. When the observations are nonnegative linear combinations of nonnegative sources, the correlation coefficients of the observations are larger than these of source signals. In this letter, a novel Nonnegative Matrix Factorization (NMF) algorithm with least correlated component constraints to blind separation of convolutive mixed sources is proposed. The algorithm relaxes the source independence assumption and has low-complexity algebraic com- putations. Simulation results on blind source separation including real face image data indicate that the sources can be successfully recovered with the algorithm. 展开更多
关键词 矩阵分解算法 信号分离 卷积 混源 非负矩阵分解 统计独立 盲源分离 甲基甲酰胺
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Multiple moving sources passive location based on multiset canonical correlation analysis
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作者 禹华钢 Huang Gaoming Gao Jun 《High Technology Letters》 EI CAS 2013年第2期197-202,共6页
To solve the problem of multiple moving sources passive location,a novel blind source separation(BSS) algorithm based on the multiset canonical correlation analysis(MCCA) is presented by exploiting the different tempo... To solve the problem of multiple moving sources passive location,a novel blind source separation(BSS) algorithm based on the multiset canonical correlation analysis(MCCA) is presented by exploiting the different temporal structure of uncorrelated source signals first,and then on the basis of this algorithm,a novel multiple moving sources passive location method is proposed using time difference of arrival(TDOA) and frequency difference of arrival(FDOA) measurements.The key technique of this location method is TDOA and FDOA joint estimation,which is based on BSS.By blindly separating mixed signals from multiple moving sources,the multiple sources location problem can be translated to each source location in turn,and the effect of interference and noise can also be removed.The simulation results illustrate that the performance of the MCCA algorithm is very good with relatively light computation burden,and the location algorithm is relatively simple and effective. 展开更多
关键词 典型相关分析 无源定位 基础 移动 盲源分离 到达频差 TDOA 定位方法
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Cross-Correlation Detection of Point Sources in the WMAP First Year Data
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作者 Jian-Yin Nie Shuang-Nan Zhang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第2期199-208,共10页
We apply a Cross-Correlation (CC) method developed previously for detecting gamma-ray point sources to the WMAP first year data by using the Point-Spread Function of WMAP and obtain a full sky CC coefficient map. We... We apply a Cross-Correlation (CC) method developed previously for detecting gamma-ray point sources to the WMAP first year data by using the Point-Spread Function of WMAP and obtain a full sky CC coefficient map. We find that the CC method is a powerful tool to examine the WMAP foreground residuals which can be further cleaned accord- ingly. Evident foreground signals are found in the WMAP foreground cleaned maps and the Tegmark cleaned map. In this process 101 point sources are detected, and 26 of them are new sources additional to the originally listed WMAP 208 sources. We estimate the flux of these new sources and verify them by another method. As a result, a revised mask file based on the WMAP first year data is produced by including these new sources. 展开更多
关键词 cosmic microwave background: WMAP - cross-correlation - radio point source
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An Iterative Detection/Decoding Algorithm of Correlated Sources for the LDPC-Based Relay Systems 被引量:1
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作者 Haiqiang Chen Hang Cao +3 位作者 Xiangcheng Li Youming Sun Haibin Wan Tuanfa Qin 《China Communications》 SCIE CSCD 2017年第9期190-198,共9页
An iterative detection/decoding algorithm of correlated sources for the LDPC-based relay systems is presented. The signal from the source-destination(S-D) link is formulated as a highly correlated counterpart from the... An iterative detection/decoding algorithm of correlated sources for the LDPC-based relay systems is presented. The signal from the source-destination(S-D) link is formulated as a highly correlated counterpart from the relay-destination(R-D) link. A special XOR vector is defined using the correlated hard decision information blocks from two decoders and the extrinsic information exchanged between the two decoders is derived by the log-likelihood ratio(LLR) associated with the XOR vector. Such the decoding scheme is different from the traditional turbo-like detection/decoding algorithm, where the extrinsic information is computed by the side information and the soft decoder outputs. Simulations show that the presented algorithm has a slightly better performance than the traditional turbo-like algorithm(Taking the(255,175) EG-LDPC code as an example, it achieves about 0.1 dB performance gains aroundBLER=10^(-4)). Furthermore, the presented algorithm requires fewer computing operations per iteration and has faster convergence rate. For example, the average iteration of the presented algorithm is 33 at SNR=1.8 dB, which is about twice faster than that of the turbo-like algorithm, when decoding the(961,721) QC-LDPC code. Therefore, the presented decoding algorithm of correlated sources provides an alternative decoding solution for the LDPC-based relay systems. 展开更多
关键词 correlATED sources ITERATIVE de-coding LDPC CODES RELAY channel
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Oil Source and Entrapment Epoch of the Ordovician Oil Reservoir in the Kongxi Burial-Hill Zone, Huanghua Depression, North China 被引量:4
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作者 王铁冠 王飞宇 +3 位作者 卢鸿 杨池银 廖前进 周建生 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第2期212-219,共8页
An oil flow obtained from the Middle Ordovician Fengfeng Formation carbonate reservoir in the well KG-3, Kongxi burial-hill zone in 1993 marked a breakthrough in petroleum exploration of the high-mature Lower Palaeozo... An oil flow obtained from the Middle Ordovician Fengfeng Formation carbonate reservoir in the well KG-3, Kongxi burial-hill zone in 1993 marked a breakthrough in petroleum exploration of the high-mature Lower Palaeozoic strata, North China. Both the Lower member of the Fengfeng Formation and the Second Member of the Upper Majiagou Formation in the Middle Ordovician are supposed to be the main source beds. Oil generation peaks range from 1.0% to 1.6% in Ro, showing a “lag effect” of oil generation in high-mature carbonate source rocks under multicyclic tectonic movement conditions. The Kongxi burial-hill zone adjoins a potential Ordovician source kitchen. The KG-3 Ordovician burial-hill reservoir has undergone two oil filling events, i.e., an early event in the Late Carboniferous-Permian and a more significant late event in the early Eogene. 展开更多
关键词 burial-hill reservoir source rocks “lag effect” oil-source correlation oil entrapment epoch
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