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“老水手”的漫长旅程——从文学视窗中看人类生态意识的衍变 被引量:6
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作者 胡泓 《安徽师范大学学报(社会科学版)》 2002年第5期578-583,共6页
用现代生态学的观点去阅读过去的一些文学作品 ,我们将会发现人类现代的环境保护意识和生态平衡意识并非诞生于一朝一夕 ,它们和人类的自然观一样也经历了一个漫长而曲折的衍变过程 ,通过分析柯勒律治的《古舟子咏》、麦尔维尔的《白鲸... 用现代生态学的观点去阅读过去的一些文学作品 ,我们将会发现人类现代的环境保护意识和生态平衡意识并非诞生于一朝一夕 ,它们和人类的自然观一样也经历了一个漫长而曲折的衍变过程 ,通过分析柯勒律治的《古舟子咏》、麦尔维尔的《白鲸》、以及海明威的《老人与海》 ,揭示这一过程中所表现出来的三种主要形态 :物我相亲、物我相征、以及相亲与相征并存。 展开更多
关键词 生态意识 人类 自然 自然观 相亲 相征
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Rolling bearing fault diagnosis based on data-level and feature-level information fusion
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作者 Shu Yongdong Ma Tianchi Lin Yonggang 《Journal of Southeast University(English Edition)》 EI CAS 2024年第4期396-402,共7页
To address the limitation of single acceleration sensor signals in effectively reflecting the health status of rolling bearings,a rolling bearing fault diagnosis method based on the fusion of data-level and feature-le... To address the limitation of single acceleration sensor signals in effectively reflecting the health status of rolling bearings,a rolling bearing fault diagnosis method based on the fusion of data-level and feature-level information was proposed.First,according to the impact characteristics of rolling bearing faults,correlation kurtosis rules were designed to guide the weight distribution of multi-sensor signals.These rules were then combined with a weighted fusion method to obtain high-quality data-level fusion signals.Subsequently,a feature-fusion convolutional neural network(FFCNN)that merges the one-dimensional(1D)features extracted from the fused signal with the two-dimensional(2D)features extracted from the wavelet time-frequency spectrum was designed to obtain a comprehensive representation of the health status of rolling bearings.Finally,the fused features were fed into a Softmax classifier to complete the fault diagnosis.The results show that the proposed method exhibits an average test accuracy of over 99.00%on the two rolling bearing fault datasets,outperforming other comparison methods.Thus,the method can be effectively utilized for diagnosing rolling bearing faults. 展开更多
关键词 fault diagnosis information fusion correlation kurtosis feature-fusion convolutional neural network
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Characterization and evaluation of interface in SiC_p/2024 Al composite 被引量:9
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作者 柳培 王爱琴 +1 位作者 谢敬佩 郝世明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1410-1418,共9页
35% SiCp/2024 Al(volume fraction) composite was prepared by powder metallurgy method. The microstructures of Si Cp/Al interfaces and precipitate phase/Al interfaces were characterized by HRTEM, and the interface con... 35% SiCp/2024 Al(volume fraction) composite was prepared by powder metallurgy method. The microstructures of Si Cp/Al interfaces and precipitate phase/Al interfaces were characterized by HRTEM, and the interface conditions were evaluated by tensile modules of elasticity and Brinell hardness measurement. The results show that the overall Si Cp/Al interface condition in this experiment is good and three kinds of Si Cp/Al interfaces are present in the composites, which include vast majority of clean planer interfaces, few slight reaction interfaces and tiny amorphous interfaces. The combination mechanism of Si C and Al in the clean planer interface is the formation of a semi-coherent interface by closely matching of atoms and there are no fixed or preferential crystallographic orientation relationships between Si C and Al. MgAl2O4 spinel particles act as an intermediate to form semi-coherent interface with SiC and Al respectively at the slight reaction interfaces. When the composite is aged at 190 °C for 9 h after being solution-treated at 510 °C for 2 h, numerous discoid-shaped and needle-shaped nanosized precipitates dispersively exist in the composite and are semi-coherent of low mismatch with Al matrix. The Brinell hardness of composites arrives peak value at this time. 展开更多
关键词 SiCp/2024 Al composite INTERFACE precipitate phase CHARACTERIZATION
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Doped-Chamber Deposition of Intrinsic Microcrystalline Silicon Thin Films and Its Application in Solar Cells 被引量:1
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作者 孙福河 张晓丹 +9 位作者 赵颖 王世峰 韩晓艳 李贵军 魏长春 孙建 侯国付 张德坤 耿新华 熊绍珍 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第5期855-858,共4页
A series of microcrystalline silicon thin films were fabricated by very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) at different silane concentrations in a P chamber. Through analysis of the... A series of microcrystalline silicon thin films were fabricated by very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) at different silane concentrations in a P chamber. Through analysis of the structural and electrical properties of these materials,we conclude that the photosensitivity slightly decreased then increased as the silane concentration increased,while the crystalline volume fraction indicates the opposite change. Results of XRD indicate that thin films have a (220) preferable orientation under certain conditions. Microcrystalline silicon solar cells with conversion efficiency 4. 7% and micromorph tandem solar cells 8.5% were fabricated by VHF-PECVD (p layer and i layer of microcrystalline silicon solar cells were deposited in P chamber), respectively. 展开更多
关键词 VHF-PECVD intrinsic microcrystalline silicon solar cells
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PHASE AUTOFOCUSING ALGORITHM FOR COMPRESSED INVERSE SYNTHETIC APERTURE RADAR IMAGING 被引量:3
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作者 朱岱寅 张伟 朱兆达 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第3期245-253,共9页
As same as the conventional inverse synthetic aperture radar(ISAR), the compressed ISAR also requires the echo signal based motion compensation, which consists of the range alignment and the phase autofoeusing. A ph... As same as the conventional inverse synthetic aperture radar(ISAR), the compressed ISAR also requires the echo signal based motion compensation, which consists of the range alignment and the phase autofoeusing. A phase autofocusing algorithm for compressed ISAR imaging is presented. In the algorithm, phase autofocusing for the sparse ISAR echoes is accomplished using the eigenvector method. Experimental results validate the effectiveness of the algorithm. 展开更多
关键词 compressed inverse synthetic aperture radar (ISAR) autofocusing phase compensation eigenvector method
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Dynamical chiral symmetry breaking in QED_3 被引量:1
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作者 周雨青 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期544-549,共6页
In order to examine how a propagator behaves in non-perturbative theories and how its behavior is influenced by the choice of a covariant gauge a truncated Dyson-Schwinger equation is used to numerically investigate t... In order to examine how a propagator behaves in non-perturbative theories and how its behavior is influenced by the choice of a covariant gauge a truncated Dyson-Schwinger equation is used to numerically investigate the properties of fermions and bosons in 3D quantum electrodynamics QED and a series of self-consistent solutions for the fermion propagator in the Nambu and Wigner phases are obtained. These numerical solutions show that the propagator behaves very differently in the Landau gauge domain and in the infrared energy region outside it.By using the propagators in the Nambu and Wigner phases under various gauges it is further investigated how the fermion equivalent pressure difference and fermion condensation change with the gauge parameters.These results indicate that the phase transition described by the CJT equivalent potential and the chiral phase transition described by the chiral condensation are not completely identical. 展开更多
关键词 PROPAGATOR covariant gauge 3D quantumelectrodynamics QED equivalent pressure difference fermion condensation chiral phase transition
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APPLICATION OF IMPROVED EMD IN VIBRATION SIGNAL FEATURE EXTRACTION OF VEHICLE
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作者 辛江慧 安木金 +1 位作者 张雨 任成龙 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期193-198,共6页
In order to truly obtain the feature extraction of vibration signals under the strong background noise, the analysis and improvement of empirical mode decomposition (EMD) is carried on. After that, the improved EMD ... In order to truly obtain the feature extraction of vibration signals under the strong background noise, the analysis and improvement of empirical mode decomposition (EMD) is carried on. After that, the improved EMD is applied to the feature extraction of vehicle vibration signals. First, the multi-autocorrelation method is adopted in each input signal,so the noise is reduced effectively. Then, EMD is used to deal with these signals,and the intrinsic mode functions (IMFs) are obtained. Finally, for obtaining the feature information of these signals, the Hilbert transformation and the spectrum analysis are performed in some IMFs. Theoretical analysis and ex- periment verify the effectiveness of the method, which are valuable reference for the same engineering problems. 展开更多
关键词 empirical mode decomposition (EMD) vehicle vibration signal multi-autocorrelation feature ex- traction
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Architecture and algorithm for web phishing detection
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作者 曹玖新 王田峰 +1 位作者 时莉莉 毛波 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期43-47,共5页
A phishing detection system, which comprises client-side filtering plug-in, analysis center and protected sites, is proposed. An image-based similarity detection algorithm is conceived to calculate the similarity of t... A phishing detection system, which comprises client-side filtering plug-in, analysis center and protected sites, is proposed. An image-based similarity detection algorithm is conceived to calculate the similarity of two web pages. The web pages are first converted into images, and then divided into sub-images with iterated dividing and shrinking. After that, the attributes of sub-images including color histograms, gray histograms and size parameters are computed to construct the attributed relational graph(ARG)of each page. In order to match two ARGs, the inner earth mover's distances(EMD)between every two nodes coming from each ARG respectively are first computed, and then the similarity of web pages by the outer EMD between two ARGs is worked out to detect phishing web pages. The experimental results show that the proposed architecture and algorithm has good robustness along with scalability, and can effectively detect phishing. 展开更多
关键词 phishing detection image similarity attributed relational graph inner EMD outer EMD
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Characterization of SiC nanowires prepared on C/C composite without catalyst by CVD 被引量:3
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作者 葛毅成 刘云启 +3 位作者 武帅 吴皇 毛佩林 易茂中 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第10期3258-3264,共7页
SiC nanowires were prepared on C/C composite surface without catalyst by chemical vapor deposition(CVD) using CH3 SiCl3 as precursor.SEM images of the CVD-product reveal that some long nanowires have grown to tens o... SiC nanowires were prepared on C/C composite surface without catalyst by chemical vapor deposition(CVD) using CH3 SiCl3 as precursor.SEM images of the CVD-product reveal that some long nanowires have grown to tens of micrometers with some gathered as a ball.Some short nanowires agglomerate like chestnut shell with many thorns accompanied by some deposited nano-particles.XRD,Raman-spectrum and FTIR patterns indicate that the product is a typical β-SiC.TEM images show that the nanowires have a wide diameter range from 10 to 100 nm,and some thin nanowires are bonded to the thick one by amorphous CVD-SiC.A SiC branch generates from an amorphous section of a thick one with an angle of 70° between them,which is consistent with the [111] axis stacking angle of the crystal.SAED and fast Fourier transform(FFT) patterns reveal that the nanowires can grow along with different axes,and the bamboo-nodes section is full of stacking faults and twin crystal.The twisted SiC lattice planes reveal that the screw dislocation growth is the main mechanism for the CVD-SiC nanowires. 展开更多
关键词 SiC nanowires C/C composite chemical vapor deposition growth mechanism CHARACTERIZATION
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Elastic Behaviors of Adsorbed Protein-like Chains
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作者 孙婷婷 马海珠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期11-17,I0001,共8页
Elastic behaviors of protein-like chains are investigated by Pruned-Enriched-Rosenbluth method and modified orientation-dependent monomer-monomer interactions model. The protein-like chain is pulled away from the attr... Elastic behaviors of protein-like chains are investigated by Pruned-Enriched-Rosenbluth method and modified orientation-dependent monomer-monomer interactions model. The protein-like chain is pulled away from the attractive surface slowly with elastic force acting on it. Strong adsorption interaction and no adsorption interaction are both considered. We calculate the characteristic ratio and shape factor of protein-like chains in the process of elongation. The conformation change of the protein-like chain is well depicted. The shape of chain changes from “rod” to “sphere” at the beginning of elongation. Then, the shape changes from “sphere” to “rod”. In the end, the shape becomes a “sphere” as the chain leaves away from the surface. In the meantime, we discuss average Helmoholtz free energy per bond, average energy per bond, average adsorbed energy per bond, average α-helical energy per bond, average β-sheet energy per bond and average contact energy per bond. On the other hand, elastic force is also studied. It is found that elastic force has a long plateau during the tensile elongation when there exists adsorption interaction. This result is consistent with SMFS experiment of general polymers. Energy contribution to elastic force and contact energy contribution to elastic force are both discussed. These investigations can provide some insights into the elastic behaviors of adsorbed protein chains. 展开更多
关键词 Elastic behavior Adsorbed protein-like chain Pruned-Enriched-Rosenbluth method Orientation-dependent monomer-monomer interactions model
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Effect of Radiative Forcing on Growth and Photosynthetic Responses of Elaeocarpus glabripetalus Merr.
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作者 杨爽 江洪 翟秀丽 《Agricultural Science & Technology》 CAS 2012年第6期1240-1246,共7页
[Objective] This study aimed to reveal the impact of radiative forcing on the woody plants in subtropical regions of China through the study on the effect of radiative forcing on growth and photosynthetic responses of... [Objective] This study aimed to reveal the impact of radiative forcing on the woody plants in subtropical regions of China through the study on the effect of radiative forcing on growth and photosynthetic responses of Elaecarpus glabripetalus Merr. seedlings. [Method] Three gradients of radiative forcing treatments were applied to the species namely, control group (100% natural light), weak radiative forcing group (39% natural light) and strong radiative forcing group (16% natural light). The relative contents of chlorophyll, photosynthetic parameters of E. glabripetalus in different periods were measured to analyze the effects of different gradients of radiative forcing on plant height, ground diameter, chlorophyll content, gas exchange parameters, light response cure parameters. [Result] The increased ground diameter of E. glabripetalus in different treatments was the control weak radiative forcing group strong radiative forcing group; the increased plant height in the early period was strong radiative forcing group weak radiative forcing group control, but there was no significant difference during the late period; the relative content of chlorophyll was strong radiative forcing group weak radiative forcing group control. The light compensation point (LCP), light saturation point (LSP) and the maximum net photosynthetic rate (A max ) were reduced in radiative forcing treatments. The stomatal conductance (G s ), transpiration rate (Tr) of E. glabripetalus in strong radiative forcing group were significantly smaller than that in the control group, while there was no significant change in dark respiration rate (R d ) and apparent quantum yield (AQY). [Conclusion] In summary, the radiative forcing can change the environmental factors which have significant effect on the ground diameter, plant height, relative content of chlorophyll and photosynthetic physiological parameters, but with the processing of treatment the effects on ground diameter and plant height increase are not significant in the late period, indicating that E. glabripetalus seedlings have some resistance and adaptability to the radiative forcing environment. 展开更多
关键词 Radiative forcing Elaeocarpus glabripetalus Merr. Chlorophyll relative content Photosynthetic characteristic
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Pre-stack-texture-based reservoir characteristics and seismic facies analysis 被引量:3
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作者 宋承云 刘致宁 +2 位作者 蔡涵鹏 钱峰 胡光岷 《Applied Geophysics》 SCIE CSCD 2016年第1期69-79,219,共12页
Seismic texture attributes are closely related to seismic facies and reservoir characteristics and are thus widely used in seismic data interpretation.However,information is mislaid in the stacking process when tradit... Seismic texture attributes are closely related to seismic facies and reservoir characteristics and are thus widely used in seismic data interpretation.However,information is mislaid in the stacking process when traditional texture attributes are extracted from poststack data,which is detrimental to complex reservoir description.In this study,pre-stack texture attributes are introduced,these attributes can not only capable of precisely depicting the lateral continuity of waveforms between different reflection points but also reflect amplitude versus offset,anisotropy,and heterogeneity in the medium.Due to its strong ability to represent stratigraphies,a pre-stack-data-based seismic facies analysis method is proposed using the selforganizing map algorithm.This method is tested on wide azimuth seismic data from China,and the advantages of pre-stack texture attributes in the description of stratum lateral changes are verified,in addition to the method's ability to reveal anisotropy and heterogeneity characteristics.The pre-stack texture classification results effectively distinguish different seismic reflection patterns,thereby providing reliable evidence for use in seismic facies analysis. 展开更多
关键词 Pre-stack texture attributes reservoir characteristic seismic facies analysis SOM clustering gray level co-occurrence matrix
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The BLOC Interactomes Form a Network in Endosomal Transport 被引量:1
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作者 李巍 冯雅琴 +4 位作者 郝婵娟 郭小黎 崔艳艳 贺敏 何新 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第8期669-682,共14页
With the identification of more than a dozen novel Hermansky-Pudlak Syndrome (HPS) proteins in vesicle trafficking in higher eukaryotes, a new class of trafficking pathways has been described. It mainly consists of ... With the identification of more than a dozen novel Hermansky-Pudlak Syndrome (HPS) proteins in vesicle trafficking in higher eukaryotes, a new class of trafficking pathways has been described. It mainly consists of three newly-defined protein com- plexes, BLOC-l, -2, and -3. Compelling evidence indicates that these complexes together with two other well-known complexes, AP3 and HOPS, play important roles in endosomal transport. The interactions between these complexes form a network in protein trafficking via endosomes and cytoskeleton. Each node of this network has intra-complex and extra-complex interactions. These complexes are connected by direct interactions between the subunits from different complexes or by indirect interactions through coupling nodes that interact with two or more subunits from different complexes. The dissection of this network facilitates the understanding of a dynamic but elaborate transport machinery in protein/membrane trafficking. The disruption of this network may lead to abnormal trafficking or defective organellar development as described in patients with Hermansky-Pudlak syndrome. 展开更多
关键词 biogenesis of lysosome-related organelles complex (BLOC) endosomal transport protein interactome Hermansky-Pudlak
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Comethylation of p16 and MGMT genes in colorectal carcinoma:Correlation with clinicopathological features and prognostic value 被引量:10
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作者 Koviljka Krtolica Milena Krajnovic +3 位作者 Slavica Usaj-Knezevic Dragan Babic Dusan Jovanovic Bogomir Dimitrijevic 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第8期1187-1194,共8页
AIM: To investigate the significance of p16 and O6- methylguanine-DNA methyltransferase (MGMT) genes promoter hypermethylation and K-ras mutations on colorectal tumorigenesis and progression. METHODS: p16 and MGMT met... AIM: To investigate the significance of p16 and O6- methylguanine-DNA methyltransferase (MGMT) genes promoter hypermethylation and K-ras mutations on colorectal tumorigenesis and progression. METHODS: p16 and MGMT methylation status was examined on 47 tumor samples, and K-ras mutational status was examined on 85 tumor samples. For methylation analysis, a methylation specific PCR (MS-PCR) method was used. RESULTS: p16 and MGMT promoter methylation was found in 51% (24/47) and 43% (20/47) of CRCs, respectively, and the K-ras mutation was found in 44% (37/85) of CRCs. Comethylation of p16 and MGMT genes was significantly associated with lower aggressiveness of the disease within a two-year period of observation. Only 27% of patients with simultaneous p 16 and MGMT methylation showed the detectible occurrence of metastasis and/or death, compared to 67% of patients without double methylation or with no methylation (3/11 vs 22/33, P < 0.05, χ2-test). In addition, p16 and MGMT comethylation showed a trend toward an association with longer survival in patients with CRCs (35.5 ± 6.0 mo vs 23.1 ± 3.2 mo, P = 0.072, Log-rank test). Progression of the disease within a two-year period was observed in 66% of patients carrying the K-ras mutation, compared to only 19% of patients with wild type K-ras (29/44 vs 7/37, P < 0.001, χ2-test). The presence of the K-ras mutation significantly correlated to shortened overall survival (20.0 ± 1.9 mo vs 37.0 ± 1.8 mo, P < 0.001, Log-rank test). The comethylation of p16 and MGMT genes was significantly associated with lower aggressiveness of the disease even when K-ras mutations were included in the analysis as an independent variable. CONCLUSION: Our data suggest that comethylation of promoters of p 16 and MGMT genes could have a prognostic value in patients with CRC. Specifically, concurrent methylation of both genes correlates with better prognosis. 展开更多
关键词 Colorectal carcinoma DNA methylation P16 MGMT K-ras mutation
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Contrast-enhanced multiple-phase imaging features in hepatic epithelioid hemangioendothelioma 被引量:12
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作者 Ying Chen Ri-Sheng Yu +3 位作者 Ling-Ling Qiu Ding-Yao Jiang Yan-Bin Tan Yan-Biao Fu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第30期3544-3553,共10页
AIM: To investigate and review the contrast-enhanced multiple-phase computed tomography (CEMP CT) and magnetic resonance imaging (MRI) findings in patients with pathologically confirmed hepatic epithelioid hemang... AIM: To investigate and review the contrast-enhanced multiple-phase computed tomography (CEMP CT) and magnetic resonance imaging (MRI) findings in patients with pathologically confirmed hepatic epithelioid hemangioendothelioma (HEHE). METHODS: Findings from imaging examinations in 8 patients (5 women and 3 men) with pathologically confirmed HEHE were retrospectively reviewed (CT images obtained from 7 patients and MR images obtained from 6 patients). The age of presentation varied from 27 years to 60 years (average age 39.8 years). RESULTS: There were two types of HEHE: multifocal type (n = 7) and diffuse type (n = 1). Tn the multifocal-type cases, there were 74 lesions on CT and 28 lesions on MRI with 7 lesions found with diffusion weighted imaging; 18 (24.3%) of 74 lesions on plain CT and 26 (92.9%) of 28 lesions on pre-contrast MRI showed the target sign. On CEMP CT, 28 (37.8%) of 74 lesions appeared with the target sign and a progressive-enhancement rim and 9 (12.2%) of 74 lesions displayed progressive enhancement, maintaining a state of persistent enhancement. On CEMP MRI, 27 (96.4%) of 28 lesions appeared with the target sign with a progressive-enhancement rim and 28 (100%) of 28 lesions displayed progressive-enhancement, maintaining a state of persistent enhancement. In the diffuse-type cases, an enlarged liver was observed with a large nodule appearing with persistent enhancement on CEMP CT and MRI. CONCLUSION: The most important imaging features of HEHE are the target sign and/or progressive en- hancement with persistent enhancement on CEMP CT and MRI. MRI is advantageous over CT in displaying these imaging features. 展开更多
关键词 Liver NEOPLASM Epithelioid hemangioen-dothelioma Computed tomography Magnetic resonance imaging
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HIERARCHIC GREY QUASI-PREFERRED ANALYSIS MODEL AND ITS APPLICATION
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作者 李炳军 刘思峰 任盈盈 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第1期78-83,共6页
The grey quasi-preferred analysis (GQPA) is one of important methods for realizing system analysis to conquer the limitations of the existing GQPA model, without any considerations to the difference of the different b... The grey quasi-preferred analysis (GQPA) is one of important methods for realizing system analysis to conquer the limitations of the existing GQPA model, without any considerations to the difference of the different behavioral factor′s importance. It could not be used to analyze the complex system with multi-hierarchy correlation factors, the weighted synthetic method for calculating abstract incidence degrees between the system beha-vioral characteristics and correlative factors in different hierarchies is given out,and the hierarchic grey quasi-preferred analysis (HGQPA) model is established. The effectiveness of the HGQPA model is tested by the scientific-technical system of Jiangsu Province. The depth and the range of the application of GQPA are developed, and the HGQPA model is regarded as a new approach to systemically analyze the complex systems with multi-hierarchy correlation factors. 展开更多
关键词 multi-hierarchy quasi-preferred analysis MODEL grey system
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Braided river and distribution patterns of sand bodies of Jurassic Badaowan formation in Block T13 of Junggar basin 被引量:4
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作者 SUN Xiaofang JIN Zhenkui +2 位作者 WANG Zhaofeng HUANG Xiaoping GU Junfeng 《Mining Science and Technology》 EI CAS 2010年第3期446-452,共7页
In order to determine the planar and volume distribution of sand bodies of the Jurassic Badaowan formation in Block T13 of Junggar basin,we used analysis of field outcrop and 3D seismic data,which play an essential ro... In order to determine the planar and volume distribution of sand bodies of the Jurassic Badaowan formation in Block T13 of Junggar basin,we used analysis of field outcrop and 3D seismic data,which play an essential role in areas of sparse well coverage.We describe sedimentary facies characteristics,sand body planforms,width and connectivity patterns of sand bodies,and vertical associations and successions by acoustic impedance inversion technology and sedimentological theory.Results of our study show braided fluvial strata deposits in the Jurassic Badaowan formation.Each sand body is approximately lenticular in shape.The width of each sand body falls in the range 100~800 m,with most between 200 and 400 m.The sand bodies vary in thickness from 4 to 13 m,with most below 9 m.The width/thickness ratios lie in the range 20~55.The connectivity of braided fluvial channel sand bodies is controlled by changes of accommodation space.One fining-upward sedimentary cycle of base-level rise is recognized in Badaowan formation,representing an upward rise of base level.The connectivity of sand bodies was found to be greatest in the early stage of base-level rise,becoming progressively worse with increasing base-level rise. 展开更多
关键词 Block T13 Badaowan formation braided river sand body distribution patterns
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A novel shapelet transformation method for classification of multivariate time series with dynamic discriminative subsequence and application in anode current signals 被引量:3
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作者 WAN Xiao-xue CHEN Xiao-fang +2 位作者 GUI Wei-hua YUE Wei-chao XIE Yong-fang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期114-131,共18页
Classification of multi-dimension time series(MTS) plays an important role in knowledge discovery of time series. Many methods for MTS classification have been presented. However, most of these methods did not conside... Classification of multi-dimension time series(MTS) plays an important role in knowledge discovery of time series. Many methods for MTS classification have been presented. However, most of these methods did not consider the kind of MTS whose discriminative subsequence was not restricted to one dimension and dynamic. In order to solve the above problem, a method to extract new features with extended shapelet transformation is proposed in this study. First, key features is extracted to replace k shapelets to calculate distance, which are extracted from candidate shapelets with one class for all dimensions. Second, feature of similarity numbers as a new feature is proposed to enhance the reliability of classification. Third, because of the time-consuming searching and clustering of shapelets, distance matrix is used to reduce the computing complexity. Experiments are carried out on public dataset and the results illustrate the effectiveness of the proposed method. Moreover, anode current signals(ACS) in the aluminum reduction cell are the aforementioned MTS, and the proposed method is successfully applied to the classification of ACS. 展开更多
关键词 anode current signals key features distance matrix feature of similarity numbers shapelet transformation
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Structural Characteristics of Mesophase Spheres Prepared from Coal Tar Pitch Modified by Phenolic Resin 被引量:10
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作者 李同起 刘秀军 +1 位作者 王成扬 王慧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第5期660-664,共5页
Mesocarbon microbeads (MCMB) were prepared from coal tar pitch modified by phenolic resin and from the same pitch modified by phenolic resin and hexamethylenetetramine at 440℃ for lh. By investigating the morpholog... Mesocarbon microbeads (MCMB) were prepared from coal tar pitch modified by phenolic resin and from the same pitch modified by phenolic resin and hexamethylenetetramine at 440℃ for lh. By investigating the morphology of mesophase spheres and the structure of the MCMB carbonized at 1000℃ for lh using scanning electron microscope (SEM) and XRD, it was found that phenolic resin accelerated the formation and coalescence of mesophase spheres. Some of the obtained MCMB were hi- or tri-spheres with the distorted microtextural carbon layers. Hexamethylenetetramine in the pitch modified by phenolic resin accelerated the condensation of phenolic resin and consequently expedited the combination of mesophase spheres, which was proved by the formation of some tetra-spheres. Owing to the cross-linkage of the additives, MCMB with complex structure were obtained. 展开更多
关键词 mesocarbon microbeads MESOPHASE phenolic resin scanning electron microscopy
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Prognostic significance of cell infiltrations of immunosurveillance in colorectal cancer 被引量:19
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作者 Shi-YunTan YanFan +3 位作者 He-ShengLuo Zhi-XiangShen YiGuo Liang-JiaZhao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第8期1210-1214,共5页
AIM: To determine whether the mast cell (MCs) and tumor-associated macrophage (TAMs) counts have any correlation with clinical outcome in colorectal cancer, and to investigate whether MCs undergo phenotypic changes in... AIM: To determine whether the mast cell (MCs) and tumor-associated macrophage (TAMs) counts have any correlation with clinical outcome in colorectal cancer, and to investigate whether MCs undergo phenotypic changes in colorectal cancer.METHODS: The MC and TAM counts were determined immunohistochemically in 60 patients with colorectal cancer and the depth of invasion, lymph node metastasis rate, distant metastasis rates, and survival rates were compared between patients with low (less than the mean number of positive cells) and high (more than the mean number of positive cells) cell counts.RESULTS: Both patients with a low MC count and patients with a low TAM count had significantly deeper depth of invasion than those with a high MC count and those with a high TAM count (P<0.01 and P<0.01 respectively).Patients with a high MC count and patients with a high TAM count were significantly higher showing significantly lower rates of lymph node metastasis, distant metastasis than those with a low MC count and those with a low TAM count. There were significant positive correlation between MC counts and TAM counts (r = 0.852, P<0.01).In both cancerous tissue and normal colorectal tissue,the predominant MC phenotype was MCTC. The 5-year survival rate estimated was significantly lower in both patients with a low MC count and patients with a low TAM count than in those with a high MC count and those with a high TAM count (P<0.05 and P<0.01 respectively).CONCLUSION: There appears to be a direct relationship between the number of MCs and clinical outcome in patients with colorectal cancer, even though MCs exhibited no significant phenotypic changes. TAM count is of value to predict the clinical outcome or prognosis. It is more beneficial for estimating biological character of colorectal carcinoma to combine MC and TAM counts. 展开更多
关键词 Mast cells PHENOTYPE MACROPHAGES Colorectal cancer PROGNOSIS
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