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Microearthquake reveals the lithospheric structure at midocean ridges and oceanic transform faults
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作者 Zhiteng YU Jiabiao LI Weiwei DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期697-700,共4页
Mid-ocean ridge and oceanic transforms are among the most prominent features on the seafloor surface and are crucial for understanding seafloor spreading and plate tectonic dynamics,but the deep structure of the ocean... Mid-ocean ridge and oceanic transforms are among the most prominent features on the seafloor surface and are crucial for understanding seafloor spreading and plate tectonic dynamics,but the deep structure of the oceanic lithosphere remains poorly understood.The large number of microearthquakes occurring along ridges and transforms provide valuable information for gaining an indepth view of the underlying detailed seismic structures,contributing to understanding geodynamic processes within the oceanic lithosphere.Previous studies have indicated that the maximum depth of microseismicity is controlled by the 600-℃isotherm.However,this perspective is being challenged due to increasing observations of deep earthquakes that far exceed this suggested isotherm along mid-ocean ridges and oceanic transform faults.Several mechanisms have been proposed to explain these deep events,and we suggest that local geodynamic processes(e.g.,magma supply,mylonite shear zone,longlived faults,hydrothermal vents,etc.)likely play a more important role than previously thought. 展开更多
关键词 microearthquake mid-ocean ridge oceanic transform fault oceanic lithosphere thermal structure earthquake location
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Anomaly Detection Algorithm of Power System Based on Graph Structure and Anomaly Attention
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作者 Yifan Gao Jieming Zhang +1 位作者 Zhanchen Chen Xianchao Chen 《Computers, Materials & Continua》 SCIE EI 2024年第4期493-507,共15页
In this paper, we propose a novel anomaly detection method for data centers based on a combination of graphstructure and abnormal attention mechanism. The method leverages the sensor monitoring data from targetpower s... In this paper, we propose a novel anomaly detection method for data centers based on a combination of graphstructure and abnormal attention mechanism. The method leverages the sensor monitoring data from targetpower substations to construct multidimensional time series. These time series are subsequently transformed intograph structures, and corresponding adjacency matrices are obtained. By incorporating the adjacency matricesand additional weights associated with the graph structure, an aggregation matrix is derived. The aggregationmatrix is then fed into a pre-trained graph convolutional neural network (GCN) to extract graph structure features.Moreover, both themultidimensional time series segments and the graph structure features are inputted into a pretrainedanomaly detectionmodel, resulting in corresponding anomaly detection results that help identify abnormaldata. The anomaly detection model consists of a multi-level encoder-decoder module, wherein each level includesa transformer encoder and decoder based on correlation differences. The attention module in the encoding layeradopts an abnormal attention module with a dual-branch structure. Experimental results demonstrate that ourproposed method significantly improves the accuracy and stability of anomaly detection. 展开更多
关键词 Anomaly detection transformER graph structure
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Performance Evaluation of Low-Carbon and Clean Transformation of China’s Coal Economy
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作者 Liangfeng Zhu 《Journal of Environmental Science and Engineering(B)》 2024年第1期21-38,共18页
In China,the oversupply of coal occurred in 2009,and from that year onwards,China’s coal economy began a low-carbon and clean transformation.Evaluating transformation performance is the research goal of this paper.Th... In China,the oversupply of coal occurred in 2009,and from that year onwards,China’s coal economy began a low-carbon and clean transformation.Evaluating transformation performance is the research goal of this paper.The data collection for this paper includes data on deep processing of Chinese coal products from 2009 to 2020,as well as data on asset structure evolution and financial performance of 34 listed companies in the Chinese coal mining.Entropy value method is used to calculate the entropy value of low-carbon transformation,and the regression analysis is used to study the performance of cleaner transformation,the conclusion is as follows:(1)From 2009 to 2020,in China’s total energy consumption,coal consumption accounted for 71.6%in 2009 and 56.8%in 2020,the goals set by the state have been achieved.(2)The national goal of reducing the proportion of coal consumption and reducing carbon emissions has forced the transformation of deep processing of coal products.The transformation of coal enterprises towards low-carbon and clean production has achieved remarkable results.(3)From 2009 to 2020,the non coal industry income of 34 listed companies in China’s coal mining industry increased by 8.21%annually.At the same time,the asset structure was adjusted,and nearly 80%of the asset structure evolution showed an orderly development trend.(4)The regression analysis results show that the entropy value of coal deep processing products and the entropy value of asset structure adjustment are significantly related to transformation performance.The paper proposes to summarize the successful experience of China’s coal energy economic transformation,lay a foundation for achieving the carbon peak and carbon neutral goals in the future,further increase the intensity of coal deep processing,increase the proportion of clean energy in total energy consumption,and strive to control asset operation towards the goal of increasing the proportion of non coal industry income. 展开更多
关键词 Coal economy low-carbon and clean transformation deep processing of coal evolution of asset structure performance appraisal
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Effectiveness of Land Use Structure Evolution to Industrial Structure Transformation 被引量:2
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作者 ZHOU Xian-peng ZHAI Wen-xia KE Xin-li 《Asian Agricultural Research》 2012年第4期50-51,55,共3页
Scarcity of land resources and transformation of industrial structure is a pair of contradictory elements.We derive the characteristics of land use structure and industrial structure transformation in Xining City usin... Scarcity of land resources and transformation of industrial structure is a pair of contradictory elements.We derive the characteristics of land use structure and industrial structure transformation in Xining City using Transformation Coefficient(TC):first,in the period 1999-2000,the land use structure coefficient(θ1) declined by 79.55%,but the overall evolution trend is gentle;second,the transformation coefficient of industrial structure(θ2) tended to decline ceaselessly on the whole,a decrease of 36.09%(overall,the transformation coefficient of industrial structure is slightly greater than the land use structure coefficient);third,the inter-annual variation of the two experienced ups and downs(in the period 1999-2007,the inter-annual variation was great and in the period 2008-2010,the inter-annual variation tended to be gentle).On the basis of autocorrelation and co-integration model,we draw the following conclusions through analysis:first,the land use structure in Xining City plays a role in promoting industrial structure transformation;second,there is a long-term equilibrium relationship between the two.Finally,relevant policy recommendations are put forward for the industrial development in Xining City. 展开更多
关键词 Land use structure Industrial structure transformation transformation Coefficient Xining City
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Synthesis and Structure Transformation of Orthorhombic LiMnO2 Cathode Materials by Sol-gel Method 被引量:1
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作者 ShixiZHAO HanxingLIU +1 位作者 QiangLI ShixiOUYANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第1期46-48,共3页
Orthorhombic LiMnO2 cathode materials were synthesized successfully at lower temperature by sol-gel method. When LiMnO2 precursor prepared by sol-gel method was fired in air, the product was a mixture of spinel struct... Orthorhombic LiMnO2 cathode materials were synthesized successfully at lower temperature by sol-gel method. When LiMnO2 precursor prepared by sol-gel method was fired in air, the product was a mixture of spinel structure LiMn2O4 and rock-salt structure Li2MnO3, whereas in argon single-phase orthorhombic LiMnO2 could obtain at the range of 750℃ to 920℃. The substitution of Mn by Zn2+ or Co3+ in LiMnO2 led to the structure of LiMnO2 transiting to Qα-LiFeO2. The results of electrochemical cycles indicated that the discharged capacity of orthorhombic-LiMnO2 was smaller at the initial stages, then gradually increased with the increasing of cycle number, finally the capacity stabilized to certain value after about 10th cycles. This phenomenon reveals that there is an activation process for orthorhombic LiMnO2 cathode materials during electrochemical cycles, which is a phase transition process from orthorhombic LiMnO2 to tetragonal spinel Li2Mn2O4. The capacity of orthorhombic LiMnO2 synthesized at lower temperature is larger than that synthesized at high temperature. 展开更多
关键词 Orthorhombic LiMnO2 SYNTHESIS structure transformation Sol-gel method
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MICROSTRUCTURE TRANSFORMATION IN THE WELDING HEAT AFFECTED ZONE OF 800MPa GRADE ULTRA FINE STRUCTURED STEEL 被引量:1
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作者 J.B. Liu L.J. Hu +3 位作者 Y.T.Wang Z. Q. Liu K. Miao Z.L. Tian 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第3期238-246,共9页
The transformation behavior and microstructure development in the heat affected zone(HAZ) of 800MPa grade ultra fine structured steel was investigated. It was found thatthe HAZ has intermediate temperature transformat... The transformation behavior and microstructure development in the heat affected zone(HAZ) of 800MPa grade ultra fine structured steel was investigated. It was found thatthe HAZ has intermediate temperature transformation characteristics in a wide rangeof cooling rates, with the bainite sheaves consisting of bainite ferrite plates withoutcarbide precipitation and retained austenite in the fast cooling regime. At relativelyhigh cooling rates, which corresponded to low heat inputs, the hardness of the simulatedHAZ was above that of the base metal. When the cooling rate was below 9℃/s, thewelding HAZ would have an obvious softening. The analysis of transformation ratesin continuous cooling processes was completed by numerical differential method. Theresult indicated that the microstructure transformation rate of the HAZ in 800MPagrade ultra fine structured steel changed sharply to slow speeds when the cooling timet_(8/5) is longer than 7s. 展开更多
关键词 ultra fine structured steel WELD heat affected zone transformation rate microstructure
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Novel mechanical behavior of periodic structure with the pattern transformation 被引量:1
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作者 Jianying Hu Yuhao He +1 位作者 Jincheng Lei Zishun Liu 《Theoretical & Applied Mechanics Letters》 CAS 2013年第5期35-38,共4页
Abstract In periodic cellular structures, novel pattern transformations are triggered by a reversible elastic instability under the axial compression. Based on the deformation-triggered new pattern, periodic cellular ... Abstract In periodic cellular structures, novel pattern transformations are triggered by a reversible elastic instability under the axial compression. Based on the deformation-triggered new pattern, periodic cellular structures can achieve special mechanical properties. In this paper, the designed architecture materials which include elastomer matrixes containing empty holes or filled holes with hydrogel material are modeled and simulated to investigate the mechanical property of the periodic materials. By analyzing the relationship between nominal stress and nominal strain of periodic material, and the corresponding deformed patterns, the influence of geometry and shapes of the holes on the mechanical property of architecture material is studied in more details. We hope this study can provide future perspectives for the deformation-triggered periodic structures. 展开更多
关键词 pattern transformation periodic structures composite gel material mechanical property
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Characteristic Functional Structure of Infinitesimal Symmetry Transformations for Nonholonomic System 被引量:1
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作者 张宏彬 陈立群 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期134-138,共5页
It was proved that velocity-dependent infinitesima l symmetry transformations of nonholonomic systems have a characteristic functio nal structure, which could be formulated by means of an auxiliary symmetry tra nsform... It was proved that velocity-dependent infinitesima l symmetry transformations of nonholonomic systems have a characteristic functio nal structure, which could be formulated by means of an auxiliary symmetry tra nsformation function and is manifestly dependent upon constants of motion of th e system. An example was given to illustrate the applicability of the results. 展开更多
关键词 analytical mechanics nonholonomic system velocity-dependent infinitesimal symmetry transformation characteristic functional structure constant of motion.
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Bcklund Transformation and Localized Coherent Structure for the (2+1)-Dimensional Asymmetric Nizhnik-Novikov-Veselov Equation 被引量:1
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作者 张解放 刘宇陆 《Journal of Shanghai University(English Edition)》 CAS 2002年第3期191-195,共5页
This article is concerned with the extended homogeneous balance method for studying the abundant localized solution structure of the (2+1) dimensional asymmetric Nizhnik Novikov Veselov equation. A B a¨... This article is concerned with the extended homogeneous balance method for studying the abundant localized solution structure of the (2+1) dimensional asymmetric Nizhnik Novikov Veselov equation. A B a¨ cklund transformation was first obtained, and then the richness of the localized coherent structures was found, which was caused by the entrance of two variable separated arbitrary functions, in the model. For some special choices of the arbitrary functions, it is shown that the localized structures of the model may be dromions, lumps, and ring solitons. 展开更多
关键词 homogeneous balance method coherent soliton structures asymmetric Nizhnik Novikov veselov equation (ANNV equation) B cklund transformation.
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MORPHOLOGY AND STRUCTURE OF TRANSFORMATION PRODUCTS FORMED AT INTERMEDIATE TEMPERATURE IN A Cu-Zn-Al ALLOY 被引量:1
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作者 Lu Wei Jiang Bohong Xu Zuyao 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 1992年第2期51-55,共5页
A TTT diagram for th ie precipitation formed at some intermediate temperatures through cooling from high lemperalure parenl phase in a Cu-27 27Zn-3.73Al allay is established by means of dilatormetric measurement.The m... A TTT diagram for th ie precipitation formed at some intermediate temperatures through cooling from high lemperalure parenl phase in a Cu-27 27Zn-3.73Al allay is established by means of dilatormetric measurement.The morphology and structure of transformation products formed at some intermediate tem peratures isothermally through cooling from high temperature parent phase and up-quenching from DO_(3) parent phase are studied by metallographic.X-ray and electron microscopy analyses.Three regions in the two separate C curves are obtained according to different morphology of precipitate:rod-like a,plate-like bainite and a rods,and bainite plates.Prolonged aging makes bainite plate change gradually into a whose lattice parameters are no different from that of a formed equilibriumly from parent phase.The structure is almost orthorhombic long period structure for bainites formed from B_(2) and DO_(3) parent phase,but monoclinic for martensite from DO_(3).They correspond to the overlapping and separating of(1210)and(2010)diffraction peaks respectively,showing the lower degree of ordering in bainite. 展开更多
关键词 Cu-Zn-Al alloy transformation at intermediate temperature morphology and structure
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Recognition of vortex structures in turbulent refractive index field using wavelet transformation
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作者 祁振强 冯浩楠 《Journal of Beijing Institute of Technology》 EI CAS 2012年第1期101-105,共5页
When the light wave propagates through the hypersonic flow field, the aero-optic distortion happens. It is necessary to recognize the vortex structure for studying the light propagation model. A new vortex structure r... When the light wave propagates through the hypersonic flow field, the aero-optic distortion happens. It is necessary to recognize the vortex structure for studying the light propagation model. A new vortex structure recognition method is proposed in this paper. Firstly, the refractive index field, which is transformed from the turbulent density field, is changed to gray scale images with a- bundant texture information equivalently. Then, wavelet transform is performed to decompose these images and the entropy values of the wavelet base coefficients are calculated. Comparing the entropy value to a given threshold, the modules with lower entropy are considered to be the large-scale vortex modules while those with higher entropy are small-scale vortex modules. The computer simulation results show that the proposed method is valid to recognize the vortex structures. This paper provides basis for investigation on the optics propagation model in terms of the turbulence vortex structures. 展开更多
关键词 aero-optic refractive vortex structures wavelet transform
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Reverse-transformation austenite structure control with micro/nanometer size
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作者 Hui-bin Wu Gang Niu +1 位作者 Feng-juan Wu Di Tang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第5期530-537,共8页
To control the reverse-transformation austenite structure through manipulation of the micro/nanometer grain structure, the influences of cold deformation and annealing parameters on the microstructure evolution and me... To control the reverse-transformation austenite structure through manipulation of the micro/nanometer grain structure, the influences of cold deformation and annealing parameters on the microstructure evolution and mechanical properties of 316L austenitic stainless steel were investigated. The samples were first cold-rolled, and then samples deformed to different extents were annealed at different temperatures. The microstructure evolutions were analyzed by optical microscopy, scanning electron microscopy (SEM), magnetic measurements, and X-ray diffraction (XRD); the mechanical properties are also determined by tensile tests. The results showed that the fraction of stain-induced martensite was approximately 72% in the 90% cold-rolled steel. The micro/nanometric microstructure was obtained after reversion annealing at 820-870A degrees C for 60 s. Nearly 100% reversed austenite was obtained in samples annealed at 850A degrees C, where grains with a diameter ae<currency> 500 nm accounted for 30% and those with a diameter > 0.5 mu m accounted for 70%. The micro/nanometer-grain steel exhibited not only a high strength level (approximately 959 MPa) but also a desirable elongation of approximately 45%. 展开更多
关键词 austenitic stainless steel structure control MARTENSITE reverse transformation grain refinement
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Economic Structure Transformation and Land Use Change of the Changjiang River Basin 被引量:3
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作者 WU Yingmei SU Yufang ZHANG Lei 《Chinese Geographical Science》 SCIE CSCD 2006年第4期289-293,共5页
Land, as a key factor of production, is an appropriate indicator of national and regional economic structure transformation. Land use in the Changjiang (Yangtze) River Basin (CRB) since the 1950s has experienced these... Land, as a key factor of production, is an appropriate indicator of national and regional economic structure transformation. Land use in the Changjiang (Yangtze) River Basin (CRB) since the 1950s has experienced these changes. Industrialization has been the most powerful force of the change in the regional development of the CRB. Virtually all regional resources were put into this effort to modernize the industrial production and urban construction systems of the CRB whose industrialization and urbanization has been a success story, with impressive structural change in both pro- duction and land use. These changes are evident in modern urban areas, but even more in traditionally rural areas. The regression analysis of regional development in the CRB over an extended period shows that the dominant factor in re- gional land use change is widespread industrialization in rural areas rather than the expansion of urban area. Thus, ur- banization has had a limited influence on land use change in the CRB. A major task in realizing more sustainable land use in the future development of CRB is to relocate industrial activities from rural to urban areas. 展开更多
关键词 长江流域 经济结构转变 土地利用变化 工业发展
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Hamiltonian structure, Darboux transformation for a soliton hierarchy associated with Lie algebra so(4, C)
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作者 王新赠 董焕河 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期130-136,共7页
In this paper, we first introduce a Lie algebra of the special orthogonal group, g = so(4, C), whose elements are 4 × 4trace-free, skew-symmetric complex matrices. As its application, we obtain a new soliton hier... In this paper, we first introduce a Lie algebra of the special orthogonal group, g = so(4, C), whose elements are 4 × 4trace-free, skew-symmetric complex matrices. As its application, we obtain a new soliton hierarchy which is reduced to AKNS hierarchy and present its bi-Hamiltonian structure and Liouville integrability. Furthermore, for one of the equations in the resulting hierarchy, we construct a Darboux matrix T depending on the spectral parameter λ. 展开更多
关键词 zero curvature equation recursion operator Hamiltonian structure Darboux transformation
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Urban structure transformation of Lhasa City after the peaceful liberation and democratic reform of Tibet
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作者 张樱子 ZHAO Shi-chen Atsushi DEGUCHI 《Journal of Chongqing University》 CAS 2017年第3期124-140,共17页
In Tibet, Buddhism coupled with its theocratic history has given its cities and urban areas unique forms and structures. As the political, religious, and economic center of Tibet, Lhasa City has a special urban form a... In Tibet, Buddhism coupled with its theocratic history has given its cities and urban areas unique forms and structures. As the political, religious, and economic center of Tibet, Lhasa City has a special urban form and has experienced typical urban transformation processes for a thousand years. The city has been experiencing significant urban structure transformation that has accompanied the socio-economic development in recent decades since the peaceful liberation and democratic reform of Tibet during the 1950 s. Hence, this study presents the time-series of urban structure changes in Lhasa City for the purpose of understanding the characteristics and mechanisms of transformation under the republican political system. First, the study illustrates the urban socio-economic changes of Lhasa City beginning in the 1950 s via statistical data analysis. We then divide the urban development into several stages. Subsequently, we identify the transformation characteristics of urban structure by investigating urban growth, street structure, land-use, and religious facilities via maps of the city from every development stage. This paper ultimately discusses the regulation of city transformation. This study clarifies several probable issues facing Tibetan cities and proposes suggestions for future urban development of Tibetan cities. 展开更多
关键词 urban structure transformation highland city Tibetan Buddhism theocratic governance
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PHASE TRANSFORMATION BEHAVIOR AND MICROSTRUCTURE OBSERVATION OF Nb-Ru HIGH TEMPERATURE SHAPE MEMORY ALLOY
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作者 X.Gao Y.F.Zheng +1 位作者 W.Cai L.C.Zhao 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第5期401-406,共6页
The phase transformation behavior and micro structure of Nb-Ru alloys have been studied by DSC, X-ray diffraction, optical microscopy, transmission electron microscopy (TEM) and high-resolution electron microscopy (HR... The phase transformation behavior and micro structure of Nb-Ru alloys have been studied by DSC, X-ray diffraction, optical microscopy, transmission electron microscopy (TEM) and high-resolution electron microscopy (HREM). Two-step phase transformation of CsCl (β) →face-centered tetragonal (β)→ monoclinic (β') occurs during cooling from high temperature to room temperature. The lattice parameters of marten-sites of Nb-Ru alloys were found to increase with the increase of Nb content. The martensite variants exhibit triangular self-accommodating morphology, with alternating regular bands inside. The twinning relationship between the sub structural bands was found to be (101) type I mode, and this kind of twinning interface was straight, well-defined and coherent. 展开更多
关键词 Nb-Ru alloy shape memory alloy (SMA) phase transformation micro structure.
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Finite symmetry transformation group and localized structures of the (2+1)-dimensional coupled Burgers equation
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作者 雷娅 杨铎 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期46-49,共4页
In this paper, the finite symmetry transformation group of the (2+1)-dimensional coupled Burgers equation is studied by the modified direct method, and with the help of the truncated Painleve′ expansion approach, ... In this paper, the finite symmetry transformation group of the (2+1)-dimensional coupled Burgers equation is studied by the modified direct method, and with the help of the truncated Painleve′ expansion approach, some special localized structures for the (2+1)-dimensional coupled Burgers equation are obtained, in particular, the dromion-like and solitoff-like structures. 展开更多
关键词 finite transformation group modified direct method truncated Painleve′ expansion approach localized structure
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Phase Transformation in the Infinite Layer Structure Compound (Sr, Nd) CuO_(2) and its Effect on Superconductivity
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作者 ZHOU Xingjiang YAO Yushu +2 位作者 LI JianqiXU Wei JIA Shunlian ZHAO Zhongxian 《Chinese Physics Letters》 SCIE CAS CSCD 1993年第8期503-506,共4页
Superconducting compound (Sr_(0.86)Nd_(0.14))CuO_(2 )with the infinite layer structure was synthesized under high pressure.This tetragonal structure a×a transforms into a superstructure 2√2a ×2√2a when the... Superconducting compound (Sr_(0.86)Nd_(0.14))CuO_(2 )with the infinite layer structure was synthesized under high pressure.This tetragonal structure a×a transforms into a superstructure 2√2a ×2√2a when the sample was in situ heated in transmission electron microscope to about 600K.An anormalous resistance change of the sample during heating in vacuum to 400℃ confinned the phase transformation.Aftrer the superlattice formationf the sample lost its superconductivity and became semiconducting. 展开更多
关键词 resistance transformation structure
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Spatial-temporal Heterogeneity of Industrial Structure Transformation and Carbon Emission Effects in Xuzhou Metropolitan Area 被引量:2
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作者 QIU Fangdao YUAN He +1 位作者 BAI Liangyu LI Fei 《Chinese Geographical Science》 SCIE CSCD 2017年第6期904-917,共14页
Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissi... Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissions in the Xuzhou Metropolitan Area from 2000 to 2014, with a focus on their relationships and driving factors. Our research indicates that carbon emission intensity from industrial structures in the Xuzhou Metropolitan Area at first showed an increasing trend, which then decreased. Furthermore, the relationship between emissions and industrial economic growth has been trending toward absolute decoupling. From the perspective of the center-periphery, the Xuzhou Metropolitan Area formed a concentric pattern, where both progress towards low emissions and the level of technological advancement gradually diminished from the center to the periphery. In terms of variation across provinces, the ISCB index in the eastern Henan has decreased the slowest, followed by the southern Shandong and the northern Anhui, with the northern Jiangsu ranking last. During this period, resource-and labor-intensive industries were the primary growth industries in the northern Anhui and the eastern Henan, while labor-intensive industries dominated the southern Shandong and capital-intensive industries dominated the northern Jiangsu. In terms of city types, the spatial pattern for industrial structure indicates that recession resource-based cities had higher carbon emission intensities than mature resource-based cities, followed by non-resource-based cities and regenerative resource-based cities. Generally, the industrial structure in the Xuzhou Metropolitan Area has transformed from being resource-intensive to capital-intensive, and has been trending toward technology-intensive as resource availability has been exploited to exhaustion and then been regenerated. Industrial structure has been the leading factor causing heterogeneity of carbon emission intensities between metropolitan cities. Therefore, the key to optimizing the industrial structure and layout of metropolitan areas is to promote industrial structure transformation and improve the system controlling collaborative industrial development between cities. 展开更多
关键词 碳排放强度 产业结构 时空异质性 都市圈 徐州 劳动密集型产业 技术密集型产业 资源型城市
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Design of Radome with Different Structures Based on Transformation Optics
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作者 Guanxia Yu Lijuan Xia +1 位作者 Baibing Xu Man Zhou 《Journal of Electromagnetic Analysis and Applications》 2011年第11期443-446,共4页
Basing on the transformation optics, we propose a kind of transformation method of compressing or stretching. With the method, we propose a design of transparent radome for different structures. The electromagnetic (E... Basing on the transformation optics, we propose a kind of transformation method of compressing or stretching. With the method, we propose a design of transparent radome for different structures. The electromagnetic (EM) waves inside or outside the radome can transmit through the structure without any reflection. Numerical simulations confirm the function of the radome structures. 展开更多
关键词 transformation OPTICS METAMATERIALS RADOME structure
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