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Journal of Earth Science 2019年第5期30卷 996-1004页

作者： Li Yang Wanming Yuan Xiaoyong zhu Zhen Shi Science Research Institute China University of Geosciences

The Sanjiang Tethys orogenic belt is located in the southeast side of the Qinghai-Tibet Plateau. It has undergone the opening and closing movements in different periods of Tethys oceans, complex accretive orogeny and strong mineralization from Paleozoic to Mesozoic. Using zircon fission track(ZFT) thermochronology, this study reveals the Sanjiang Tethys has experienced multi-stage tectonic activities during the Late Triassic–Cenozoic. The 15 ZFT ages with their decomposition components obtained from Sanjiang Tethysian region range from 212 to 19 Ma, which not only shows 6 age groups of 212, 179–172, 156–133, 121–96, 84–70 and 50–19 Ma, but also constrains the age limit of the tectonothermal events. These age groups recorded the Paleo-Tethys main and branches ocean opening/closure time. The age-elevation plot indicates the Sanjiang region had differential uplifting and exhumation and fast uplifting times of ca. 133, 116 and 80 Ma, coinciding with the age groups mentioned above. These results show new geochronological evidences and viewpoints.

关键词： tectonic events zircon fission track analysis tethys evolution Sanjiang region Qinghai-Tibet Plateau thermochronology

Influence of axial distance on pre-whirl regulation by the inlet guide vanes for a centrifugal pump

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Science China(Technological Sciences) 2012年第4期55卷 1037-1043页

作者： TAN Lei CAO ShuLiang WANG YuMing zhu BaoShan State Key Laboratory ofTribology Tsinghua UniversityBeijing 100084China State Key Laboratory of Hydrosc-ience and Engineering Tsinghua UniversityBeijing 100084China

The valuation of the hydraulic performance of a centrifugal pump with pre-whirl regulation of the inlet guide vanes was studied experimentally by varying the pre-whirl angle from -60° to 60° with distances between the inlet guide vanes and the impeller inlet of 280 mm, 380 mm and 460 mm. The efficiency-flow curves and the characteristic curves were obtained for the pump for various operation conditions. The experiment results demonstrated that the pre-whirl regulation widened the high efficiency zone and improved the hydraulic performance for off-design conditions with the proper pre-whirl angle. The axial distance between the inlet guide vanes and the impeller inlet influenced the pre-whirl regulation effect of the inlet guide vanes with the best pre-whirl regulation effect obtained for an axial distance of 380 mm. These results showed that an appropriate axial distance between the inlet guide vanes and the impeller inlet can improve the fluid flow at the impeller entrance with pre-whirl regulation for centrifugal pumps.

关键词： centrifugal pump inlet guide vanes axial distance pre-whirl regulation

The occurrence of gold in pyrite from the Liulincha gold ore belt,western Hunan Province,China

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Chinese Journal Of Geochemistry 2013年第4期32卷 392-397页

作者： LI Zengsheng zhu Xiaoqing LU Huanzhang HAN Tao State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences University of Chinese Academy of Sciences University of Quebec at Chicoutimi

In this study,an electron microprobe analyzer(EMPA) was used to map the spatial distribution and the occurrence of invisible gold in pyrite from the Liulincha gold ore *** data show that gold mainly occurs as submicroscopic-microscopic *** the contrast of the major guide elements of pyrite from the Liulincha gold ore belt and those from four hydrothermal-type gold deposits in the Jiaodong region,we can see the pyrites were formed in two stages:the pyrite from wall rock is mainly sedimentogenic,with simple structure;and the pyrite from ore body experienced early sedimentary process to late hydrothermal activity,the pyrite is regular in crystal form and exhibits fractured structure.

关键词：黄铁矿金矿带湖南省电子探针分析西部中国断裂结构空间分布

Perfect matchings on a type of lattices with toroidal boundary

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 33-44页

作者： FENG Xing ZHANG Lian-zhu ZHANG Ming-zu Faculty of Science Jiangxi University of Science and Technology School of Mathematical Science Xiamen University College of Mathematics and System Sciences Xinjiang University

Enumeration of perfect matchings on graphs has a longstanding interest in combinatorial mathematics. In this paper, we obtain some explicit expressions of the number of perfect matchings for a type of Archimedean lattices with toroidal boundary by applying Tesler's crossing orientations to obtain some Pfaffan orientations and enumerating their Pfaffans.

关键词： perfect matching Pfaffian orientation Archimedean lattice toroidal boundary

Ab initio STUDIES ON MAGNETISM OF 3d TRANSITION METAL DIMERS

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Acta Metallurgica Sinica(English Letters) 2007年第5期20卷 341-346页

作者： J.H. Gu Z.L. zhu School of Physical Engineering and Material Physics Laboratory Zhengzhou University Zhengzhou 450052 China

Ab initio calculations with the self-consistent full-potential linearized augmented-plane-wave method （FLAPW）, under generalized gradient approximation, have been carried out to describe the electronic and magnetic properties of 3d transition metal dimers. It predicted the antiferromagneticity of Cr2 and ferromagneticity of other species. The Mn2 dimer was shown to be ferromagnetic coupling with a local magnetic moment of 5μB. retaining the value of its free atom state. The V2 and Ni2 exhibited low spin-polarization with local magnetic moment of only 1μB per atom. On the other hand, Fe2 and Co2 were highly spin-polarized with local magnetic moments of 3 and 2μB.

关键词： magnetism 3d transition metal dimer ab initio calculation

Dissecting anxiety-related QTLs in mice by univariate and multivariate mapping

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Chinese Science Bulletin 2012年第21期57卷 2727-2732页

作者： zhu ZhiHong ZHANG ChenHao WANG XuSheng COOK Melloni N WILLIAMS Robert LU Lu zhu Jun ZJU-IBM Biocomputation Laboratory College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310058China Jiangsu Key Laboratory of Neuroregeneration Nantong UniversityNantong 226001China Department of Anatomy and Neurobiology University of Tennessee Healthy Science CenterMemphisTN 38163USA Department of Psychology University of MemphisMemphisTN 38152USA

To detect genes underlying anxiety-related traits in mice,we performed univariate and multivariate QTL mapping analyses of phenotypes obtained from 71 mice of the BXD recombinant inbred (RI) strains (n=528 mice) and their parental strains (C57BL/6J and DBA/2J).Separate and joint mapping analyses were carried out using a linkage map composed of 506 simple sequence repeats (SSRs).The main QTL effects,interactions between pairs of QTLs (epistasis),and their environmental interactions were *** results showed that anxiety-related traits were influenced by multiple QTLs (five main effect QTLs and three epistatic QTLs).Ten potential anxiety-related candidate genes within the QTL intervals on chromosomes 5,13 and 15 were *** of these genes have been reported previously to be associated with the anxiety *** on our results,it is suggested that the multivariate QTL mapping approach improves the statistical power for detecting QTL and the precision of parameter ***,multivariate mapping can also detect pleiotropic QTL effects.

关键词： QTL定位映射分析焦虑小鼠多变量单变量 QTL效应解剖

Effects of the cosmological constant on chaos in an FRW scalar field universe

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Research in Astronomy and Astrophysics 2009年第11期9卷 1185-1191页

作者： Da-zhu Ma Xin Wu Shuang-Ying Zhong Department of Physics Nanchang University Nanchang 330031 China Department of Physics Hubei University for Nationalities Enshi 445000 China

The dependence of chaos on two parameters of the cosmological constant and the self-interacting coefficient in the imaginary phase space for a closed Friedman- Robertson-Walker （FRW） universe with a conformally coupled scalar field, as the full understanding of the dependence in real phase space, is investigated numerically. It is found that Poincar6 plots for the two parameters less than 1 are almost the same as those in the absence of the cosmological constant and self-interacting terms. For energies below the energy threshold of 0.5 for the imaginary problem in which there are no cosmological constant and self-interacting terms, an abrupt transition to chaos occurs when at least one of the two parameters is 1. However, the strength of the chaos does not increase for energies larger than the threshold. For other situations of the two parameters larger than 1, chaos is weaker, and even disappears as the two parameters increase.

关键词： cosmology cosmological parameters -- methods numerical

Combo Packet:An Encryption Traffic Classification Method Based on Contextual Information

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Computers, Materials & Continua 2024年第4期79卷 1223-1243页

作者： Yuancong Chai Yuefei zhu Wei Lin Ding Li State Key Laboratory of Mathematical Engineering and Advanced Computing Information Engineering UniversityZhengzhou450001China

With the increasing proportion of encrypted traffic in cyberspace, the classification of encrypted traffic has becomea core key technology in network supervision. In recent years, many different solutions have emerged in this *** methods identify and classify traffic by extracting spatiotemporal characteristics of data flows or byte-levelfeatures of packets. However, due to changes in data transmission mediums, such as fiber optics and satellites,temporal features can exhibit significant variations due to changes in communication links and transmissionquality. Additionally, partial spatial features can change due to reasons like data reordering and *** with these challenges, identifying encrypted traffic solely based on packet byte-level features is significantlydifficult. To address this, we propose a universal packet-level encrypted traffic identification method, ComboPacket. This method utilizes convolutional neural networks to extract deep features of the current packet andits contextual information and employs spatial and channel attention mechanisms to select and locate effectivefeatures. Experimental data shows that Combo Packet can effectively distinguish between encrypted traffic servicecategories (e.g., File Transfer Protocol, FTP, and Peer-to-Peer, P2P) and encrypted traffic application categories (e.g.,BitTorrent and Skype). Validated on the ISCX VPN-non VPN dataset, it achieves classification accuracies of 97.0%and 97.1% for service and application categories, respectively. It also provides shorter training times and higherrecognition speeds. The performance and recognition capabilities of Combo Packet are significantly superior tothe existing classification methods mentioned.

关键词： Encrypted traffic classification packet-level convolutional neural network attention mechanisms

Environmental evolution recorded by multi-proxy evidence in Lake Chenghai sediments, Yunnan Province during recent 100 years

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Chinese Journal Of Geochemistry 2013年第1期32卷 47-55页

作者： zhu Zhengjie CHEN Jing'an REN Shicong ZENG Yan The State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Chongqing Key Laboratory of Exogenic Mineralization and Mine Environment Chongqing Institute of Geology and Mineral Resources Chongqing Research Center of State Key Laboratory of Coal Resources and Safe Mining

Lacustrine sediments can provide potential information about environmental changes in the past. On the basis of high-resolution multi-proxy analysis including carbon and nitrogen contents of organic matter, C/N ratios, inorganic carbon contents, and carbon and oxygen isotopic composition of carbonate, together with precise 137Cs dating, the environmental evolution of Lake Chenghai, Yunnan Province, during the past 100 years has been investigated. It is shown that the carbonate in Lake Chenghai is authigenic, and the organic matter is mainly derived from aquatic plants and algae, instead of terrestrial-source materials. The environmental evolution of Lake Chenghai can be diverged into three periods with the contrasting characteristics during the past 100 years. Before 1940, the stable carbon and oxygen isotope values, the poor correlation between them and the lower carbon and nitrogen contents of organic matter suggested that Lake Chenghai was open, and the lake water was oligotrophic during that period. During 1940-1993, the negative δ13C values and the gradual increase of carbon and nitrogen contents of organic matter and C/N ratios indicated that the eutrophication was aggravated. The closeness of Lake Chenghai and human activities may be responsible for this eutrophication. After 1993, notable increases in carbon and oxygen isotopic values of carbonate, carbon and nitrogen contents of organic matter, C/N ratios and inorganic carbon contents demonstrated that the increase of lacustrine productivity and the serious eutrophication were resulted from strong human activities. Therefore, the multi-proxy in Lake Chenghai sediments has reliably recorded the natural environmental evolution and the impacts from human activities.

关键词：湖泊沉积物环境演变多代理云南省程海氧同位素组成水体富营养化人类活动影响

Dual Space SVDD Based Radar Target Recognition from HRRP

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Chinese Journal of Electronics 2014年第2期23卷 419-425页

作者： XIAO Huaitie FENG Guoyu zhu Yongfeng HUANG Mengjun Science and Technology on Automatic Target Recognition Laboratory National University of Defense Technology

In radar target recognition based on kernel method, Support vector data description(SVDD) has been applied to High resolution range profiles(HRRPs)recognition. In this paper, first, three distribution models,i.e., Membership model, Cloud model, Gaussian mixture model, are developed to describe distribution characteristics of HRRPs in extended space. Secondly, test HRRPs in multi-target hypersphere spaces are classified, in accordance with their multi-space distributing characteristics,into two types, i.e., shrink sample and slack sample. Determination of the property of a test sample is achieved by using the minimum relative distance for shrink samples and three distribution models for slack samples, respectively. Thus three HRRP recognition methods based on dual space SVDD are formed. The extensive experiment results for HRRPs of four planes show that the proposed methods have better recognition performance than the recognition method based on single space SVDD.

关键词： High resolution range profile Support vector data description Membership model Cloud model Gaussian mixture model