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A new constitutive theory for extrusion-extensional flow of anisotropic liquid crystalline polymer fluid
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作者 Shifang Han 《Natural Science》 2011年第4期307-318,共12页
A new continuum theory of the constitutive equation of co-rotational derivative type was developed by the author for anisotropic viscoelastic fluid-liquid crystalline (LC) polymers (S.F. Han, 2008, 2010) . This paper ... A new continuum theory of the constitutive equation of co-rotational derivative type was developed by the author for anisotropic viscoelastic fluid-liquid crystalline (LC) polymers (S.F. Han, 2008, 2010) . This paper is a continuation of the recent publication [1] to study extrusion-extensional flow of the fluid. A new concept of simple anisotropic fluid is introduced. On the basis of anisotropic simple fluid, stress behavior is described by velocity gradient tensor F and spin tensor W instead of the velocity gradient tensor D in the classic Leslie?Ericksen continuum theory. A special form of the constitutive equation of the co-rotational type is established for the fluid. Using the special form of the constitutive equation in components a computational analytical theory of the extrusion-extensional flow is developed for the LC polymer liquids - anisotropic viscoelastic fluid. Application of the constitutive theory to the flow is successful in predicting bifurcation of elongational viscosity and contraction of extrudate for LC polymer liquids–anisotropic viscoelastic fluid. The contraction of extrudate of LC polymer liquids may be associated with the stored elastic energy conversion into that necessary for bifurcation of elongational viscosity in extrusion extensional flow of the fluid. 展开更多
关键词 Constitutive Equation of Co-Rotational Derivative Type Simple ANISOTROPIC FLUID Liquid Crystalline POLYMER Extrusion-extensional Flow Bifurcation of Elongational Viscosity Contraction of EXTRUDATE of LC POLYMER Liquids
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Multi-Value Sequence Generated over Sub Extension Field and Its Properties
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作者 Md. Arshad Ali Yuta Kodera +3 位作者 Takuya Kusaka Satoshi Uehara Yasuyuki Nogami Robert H. Morelos-Zaragoza 《Journal of Information Security》 2019年第3期130-154,共25页
Pseudo-random sequences with long period, low correlation, high linear complexity, and uniform distribution of bit patterns are widely used in the field of information security and cryptography. This paper proposes an... Pseudo-random sequences with long period, low correlation, high linear complexity, and uniform distribution of bit patterns are widely used in the field of information security and cryptography. This paper proposes an approach for generating a pseudo-random multi-value sequence (including a binary sequence) by utilizing a primitive polynomial, trace function, and k-th power residue symbol over the sub extension field. All our previous sequences are defined over the prime field, whereas, proposed sequence in this paper is defined over the sub extension field. Thus, it’s a new and innovative perception to consider the sub extension field during the sequence generation procedure. By considering the sub extension field, two notable outcomes are: proposed sequence holds higher linear complexity and more uniform distribution of bit patterns compared to our previous work which defined over the prime field. Additionally, other important properties of the proposed multi-value sequence such as period, autocorrelation, and cross-correlation are theoretically shown along with some experimental results. 展开更多
关键词 PSEUDO-RANDOM SEQUENCE Trace Function Power RESIDUE Symbol SUB extension Field AUTOCORRELATION CROSS-CORRELATION Linear Complexity Distribution of Bit Patterns
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Extension Modeling Strategy of Intelligent Detection in D.huoshanense Photosynthesis Process 被引量:4
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作者 Rongde Lu Can Qin Yunsheng Bao 《Intelligent Control and Automation》 2011年第2期126-132,共7页
Aiming at the limitations of the existing knowledge representations in intelligent detection, a new method of Extension-based Knowledge Representation (EKR) was proposed. The definitions, grammar rules, and storage st... Aiming at the limitations of the existing knowledge representations in intelligent detection, a new method of Extension-based Knowledge Representation (EKR) was proposed. The definitions, grammar rules, and storage structure of EKR were presented. An Extension Solving Model (ESM) based on EKR was discussed in detail, including creation of the extension constraint graph, extended inference, calculation of relevant functions and generation of extension set. A knowledge base system based on EKR and ESM was developed, which was applied in extension repository system intelligent design of detection in photosynthesis process of D.huoshanense. More reasonable results were obtained than traditional rule-based system. EKR was feasible in intelligent design to solve the problem of intelligent detection knowledge representations. 展开更多
关键词 extension-Based KNOWLEDGE Representation (EKR) Intelligent Detection extension Modeling STRATEGY (EMS) PHOTOSYNTHESIS Process of D.huoshanense (PPDH)
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Inversion of two-phase extensional basin systems during subduction of the Paleo-Pacific Plate in the SW Korean Peninsula:Implication for the Mesozoic “Laramide-style” orogeny along East Asian continental margin 被引量:1
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作者 Seung-Ik Park Jungrae Noh +4 位作者 Hee Jun Cheong Sanghoon Kwon Yungoo Song Sung Won Kim M.Santosh 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第3期909-925,共17页
During subduction, continental margins experience shortening along with inversion of extensional sedimentary basins. Here we explore a tectonic scenario for the inversion of two-phase extensional basin systems, where ... During subduction, continental margins experience shortening along with inversion of extensional sedimentary basins. Here we explore a tectonic scenario for the inversion of two-phase extensional basin systems, where the Early-Middle Jurassic intra-arc volcano-sedimentary Oseosan Volcanic Complex was developed on top of the Late Triassic-Early Jurassic post-collisional sequences, namely the Chungnam Basin. The basin shortening was accommodated mostly by contractional faults and related folds. In the basement, regional high-angle reverse faults as well as low-angle thrusts accommodate the overall shortening, and are compatible with those preserved in the cover. This suggests that their spatial and temporal development is strongly dependent on the initial basin geometry and inherited structures.Changes in transport direction observed along the basement-sedimentary cover interface is a characteristic structural feature, reflecting sequential kinematic evolution during basin inversion. Propagation of basement faults also enhanced shortening of the overlying sedimentary cover sequences. We constrain timing of the Late Jurassic-Early Cretaceous(ca. 158-110 Ma) inversion from altered K-feldspar 40 Ar/39 Ar ages in stacked thrust sheets and K-Ar illite ages of fault gouges, along with previously reported geochronological data from the area. This "non-magmatic phase" of the Daebo Orogeny is contemporaneous with the timing of magmatic quiescence across the Korean Peninsula. We propose the role of flat/low-angle subduction of the Paleo-Pacific Plate for the development of the "Laramide-style" basement-involved orogenic event along East Asian continental margin. 展开更多
关键词 TWO-PHASE extensional basin SYSTEMS Paleo-Pacific Plate INVERSION tectonics Laramide-style OROGENY East Asian continental margin
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Thin-Walled Tube Extension by Rigid Curved Punch
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作者 R. I. Nepershin 《Engineering(科研)》 2011年第5期452-460,共9页
Computer model is developed for non-steady and steady-state process of thin-walled tube extension by the rigid punch with curved profile. Rigid-plastic membrane shell theory with quadratic yield criterion is used. Tub... Computer model is developed for non-steady and steady-state process of thin-walled tube extension by the rigid punch with curved profile. Rigid-plastic membrane shell theory with quadratic yield criterion is used. Tube material normal anisotropy, work hardening, wall thickness variation and friction effects are considered. FORTRAN programs of the model predict distributions of the thickness, meridian stress, yield stress and pressure along curved generator of deformed tube and the tube extension force versus punch displacement relation. Model predictions are correlated with experimental data. 展开更多
关键词 Tube extension RIGID-PLASTIC Membrane Shell Curved RIGID PUNCH Normal ANISOTROPY Work HARDENING Wall Thickness Variation
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Mesoscale SST perturbation-induced impacts on climatological precipitation in the Kuroshio-Oyashio extension region,as revealed by the WRF simulations 被引量:3
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作者 GAO Jiaxiang ZHANG Rong-Hua WANG Hongna 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期385-397,共13页
Mesoscale coupling between perturbations of mesoscale sea surface temperature (SST) and lowlevel winds has been extensively studied using available high-resolution satellite observations. However, the climatological i... Mesoscale coupling between perturbations of mesoscale sea surface temperature (SST) and lowlevel winds has been extensively studied using available high-resolution satellite observations. However, the climatological impacts of mesoscale SST perturbations (SST meso ) on the free atmosphere have not been fully understood. In this study, the rectified eff ect of SSTmeso on local climatological precipitation in the Kuroshio- Oyashio Extension (KOE) region is investigated using the Weather Research and Forecasting (WRF) Model;two runs are performed, one forced by low-resolution SST fields (almost no mesoscale signals) and another by additional high-resolution SSTmeso fields extracted from satellite observations. Climatological precipitation response to SST meso is characterized mainly by enhanced precipitation on the warmer flank of three oceanic SST fronts in this region. The results show that the positive correlation between the 10-m wind speed perturbations and SSTmeso is well captured by the WRF model with a reasonable spatial pattern but relatively weak strength. The addition of SSTmeso improves the climatological precipitation simulated by WRF with a better representation of fine-scale structures compared with satellite observations. A closer examination on the underlying mechanism suggests that while the pressure adjustment mechanism can explain the climatological precipitation enhancement along the fronts and the relatively high contribution of the convective precipitation, other factors such as synoptic events should also be taken into consideration to account for the seasonality of the precipitation response. 展开更多
关键词 MESOSCALE SST perturbations and eff ects WRF model Kuroshio-Oyashio extension climatological PRECIPITATION
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Two-Dimensional Lithium-Ion Battery Modeling with Electrolyte and Cathode Extensions
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作者 Glyn F. Kennell Richard W. Evitts 《Advances in Chemical Engineering and Science》 2012年第4期423-434,共12页
A two-dimensional model for transport and the coupled electric field is applied to simulate a charging lithium-ion cell and investigate the effects of lithium concentration gradients within electrodes on cell performa... A two-dimensional model for transport and the coupled electric field is applied to simulate a charging lithium-ion cell and investigate the effects of lithium concentration gradients within electrodes on cell performance. The lithium concentration gradients within electrodes are affected by the cell geometry. Two different geometries are investigated: extending the length of the electrolyte past the edges of the electrodes and extending the length of the cathode past the edge of the anode. It is found that the electrolyte extension has little impact on the behavior of the electrodes, although it does increase the effective conductivity of the electrolyte in the edge region. However, the extension of the cathode past the edge of the anode, and the possibility for electrochemical reactions on the flooded electrode edges, are both found to impact the concentration gradients of lithium in electrodes and the current distribution within the electrolyte during charging. It is found that concentration gradients of lithium within electrodes may have stronger impacts on electrolytic current distributions, depending on the level of completeness of cell charge. This is because very different gradients of electric potential are expected from similar electrode gradients of lithium concentrations at different levels of cell charge, especially for the LixC6 cathode investigated in this study. This leads to the prediction of significant electric potential gradients along the electrolyte length during early cell charging, and a reduced risk of lithium deposition on the cathode edge during later cell charging, as seen experimentally by others. 展开更多
关键词 LITHIUM-ION Cell Mathematical Modeling CATHODE extension ELECTROLYTE extension Current DISTRIBUTIONS Electric and Concentration Fields
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Assessment of bearing performance degradation via extension and EEMD combined approach 被引量:18
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作者 LIU Yu-mei ZHAO Cong-cong +3 位作者 XIONG Ming-ye ZHAO Ying-hui QIAO Ning-guo TIAN Guang-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1155-1163,共9页
As a key component in rotating machinery, the operating reliability of bearing influences the performance and service life of the equipment directly. In order to describe bearing performance degradation(BPD) process e... As a key component in rotating machinery, the operating reliability of bearing influences the performance and service life of the equipment directly. In order to describe bearing performance degradation(BPD) process effectively, an assessment approach combining extension and ensemble empirical mode decomposition(EEMD) was proposed. First, the extension was utilized to construct the matter-element of bearing operating state, and the energy moment of intrinsic mode functions(IMFs) was used as characteristic parameter of the matter-element. Then, to determine classical domains of characteristic parameters, the mathematical statistics method was adopted. Finally, the BPD was analyzed qualitatively and quantitatively according to the comprehensive correlation degree of bearing current operating state related to its healthy state. The analytic results of bearing test-rig show that the proposed method indicates the incipient fault approximately occurring in the 81 st hour, and the method also quantitatively presents the degree of BPD. By contrast, the BPD assessment based on time-domain features extraction method could not achieve the above two results effectively. 展开更多
关键词 BEARING performance degradation ASSESSMENT extension ENSEMBLE empirical mode decomposition MATHEMATICAL STATISTICS
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CRYSTALLIZATION OF ORIENTED PET YARN——Spontaneous Extension of Oriented PET Yarn in Crystallization
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作者 胡学超 乔光华 +1 位作者 鲍乙巳 宋丽贞 《Journal of China Textile University(English Edition)》 EI CAS 1990年第3期1-10,共10页
This paper presents a method to measure the spontaneous extension of oriented PET fibredirectly during crystallization by twice annealing (constant-length and free-length). Samples be-fore and after the treatment were... This paper presents a method to measure the spontaneous extension of oriented PET fibredirectly during crystallization by twice annealing (constant-length and free-length). Samples be-fore and after the treatment were collected and examined by X-ray diffraction, DSC andbirefringence. The crystallinity, crystallite size, and orientation of both crystalline and amorphousparts between these samples are changed greatly which show that the extension is a consequence ofcrystallization and reorientation of uncrystallized segments along the fibre direction. The results ofthis study are not only important to understand the mechanism of supermolecular structurechanges during crystallization, but also useful to the industrial technology of crystallization spin-ning. 展开更多
关键词 CRYSTALLIZATION orientation polyethylene terephthalate (PET) ANNEALING extension shrinkage free-length ANNEALING (FLA) constant-length ANNEALING (CLA)
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Skeletal extension rate of the reef building coral <i>Porites</i>species from Aqaba and their environmental variables 被引量:2
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作者 Saber Al-Rousan 《Natural Science》 2012年第9期731-739,共9页
Annual skeletal extension rates of the sclera-actinian corals Porites species were investigated in 32 colonies from the northern Gulf of Aqaba fringing reef at various depths (1 - 42 m). All corals reveal clear and re... Annual skeletal extension rates of the sclera-actinian corals Porites species were investigated in 32 colonies from the northern Gulf of Aqaba fringing reef at various depths (1 - 42 m). All corals reveal clear and regular skeletal density banding patterns. Results showed that the high-density annual growth bands were formed during winter and the low-density annual growth bands during summer. The mean annual extension rates of the studied corals reveal a large inter-colony variability with values ranged between 2.36 to 20.0 mm/year. While a general trend of decreasing coral extension rate with depth was observed and best explained by a simple exponential model, the rates clustered into two groups: 10.86 ± 2.54 mm/year in water depths less than 10 m, and 5.23 ± 1.99 mm/year below 12 m. Light intensity seems to be the primary environmental factor responsible for decreasing coral extension rate with depth since the effect of other environmental parameters could be neglected from the Gulf of Aqaba. Time series record of the mean annual coral extension rate showed a slight increasing linear trend which could be linked to increase seawater temperature over the period of time represented. 展开更多
关键词 Coral Growth PORITES SKELETAL extension RATE Gulf of Aqaba Red Sea
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Enhancement of MAD/MIR phasing at low resolution and a new procedure for automatic phase extension
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作者 Pu Han Yuan-Xin Gu +1 位作者 Wei Ding Hai-Fu Fan 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期389-395,共7页
To achieve de novo protein structure determination of challenging cases, multi-wavelength anomalous diffraction(MAD) and multiple isomorphous replacement(MIR) phasing can be powerful tools to obtain low-resolution ini... To achieve de novo protein structure determination of challenging cases, multi-wavelength anomalous diffraction(MAD) and multiple isomorphous replacement(MIR) phasing can be powerful tools to obtain low-resolution initial phases from heavy-atom derivative datasets, then phase extension is needed against high-resolution data to obtain accurate structures.In this context, we propose a direct-methods procedure here that could improve the initial low-resolution MAD/MIR phase quality.And accordingly, an automated process for extending initial phases to high resolution is also described.These two procedures are both implanted in the newly released IPCAS pipeline.Three cases are used to perform the test, including one set of 4.17 ? MAD data from a membrane protein and two sets of MAD/MIR data with derivatives truncated down to 6.80 ? and 6.90 ?, respectively.All the results have shown that the initial phases generated from the direct-methods procedure are better than that from the conventional MAD/MIR methods.The automated phase extensions for the latter two cases starting from 6.80 ? to 3.00 ? and 6.90 ? to 2.80 ? are proved to be successful, leading to complete models.This may provide convenient and reliable tools for phase improvement and phase extension in difficult low-resolution tasks. 展开更多
关键词 direct methods MULTI-WAVELENGTH anomalous diffraction(MAD)/multiple isomorphous replacement(MIR) PHASING PHASE extension low-resolution
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Nonlinear Prediction with Deep Recurrent Neural Networks for Non-Blind Audio Bandwidth Extension 被引量:2
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作者 Lin Jiang Ruimin Hu +2 位作者 Xiaochen Wang Weiping Tu Maosheng Zhang 《China Communications》 SCIE CSCD 2018年第1期72-85,共14页
Non-blind audio bandwidth extension is a standard technique within contemporary audio codecs to efficiently code audio signals at low bitrates. In existing methods, in most cases high frequencies signal is usually gen... Non-blind audio bandwidth extension is a standard technique within contemporary audio codecs to efficiently code audio signals at low bitrates. In existing methods, in most cases high frequencies signal is usually generated by a duplication of the corresponding low frequencies and some parameters of high frequencies. However, the perception quality of coding will significantly degrade if the correlation between high frequencies and low frequencies becomes weak. In this paper, we quantitatively analyse the correlation via computing mutual information value. The analysis results show the correlation also exists in low frequency signal of the context dependent frames besides the current frame. In order to improve the perception quality of coding, we propose a novel method of high frequency coarse spectrum generation to improve the conventional replication method. In the proposed method, the coarse high frequency spectrums are generated by a nonlinear mapping model using deep recurrent neural network. The experiments confirm that the proposed method shows better performance than the reference methods. 展开更多
关键词 AUDIO CODING non-blind audiobandwidth extension context correlation deeprecurrent neural network
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Comparison of Classical Method, Extension Principle and α-Cuts and Interval Arithmetic Method in Solving System of Fuzzy Linear Equations
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作者 Sahidul Islam Md. Saiduzzaman +1 位作者 Md. Shafiqul Islam Abeda Sultana 《American Journal of Computational Mathematics》 2019年第1期1-24,共24页
The system of linear equations plays a vital role in real life problems such as optimization, economics, and engineering. The parameters of the system of linear equations are modeled by taking the experimental or obse... The system of linear equations plays a vital role in real life problems such as optimization, economics, and engineering. The parameters of the system of linear equations are modeled by taking the experimental or observation data. So the parameters of the system actually contain uncertainty rather than the crisp one. The uncertainties may be considered in term of interval or fuzzy numbers. In this paper, a detailed study of three solution techniques namely Classical Method, Extension Principle method and α-cuts and interval Arithmetic Method to solve the system of fuzzy linear equations has been done. Appropriate applications are given to illustrate each technique. Then we discuss the comparison of the different methods numerically and graphically. 展开更多
关键词 Fuzzy Set CLASSICAL Solution extension Principle α-Cut and INTERVAL ARITHMETIC METHOD
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THE EASTERN ASIA CONTINENTAL MARGIN EXTENSIONAL BELT
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作者 CHEN Guoda(Institute of Diwa Metallogeny, Central South University of Technology Changsha Institute of Geotectonics, Academia Sinica 9 Changsha, 410013, China) 《Geotectonica et Metallogenia》 1997年第Z2期1-10,共10页
From an angle of integrative analysis on historical-dynamic geotectonics, the formation mechanism of the Eastern Asia continental-margin and historical background of the evolution-movement of the crustobody are discus... From an angle of integrative analysis on historical-dynamic geotectonics, the formation mechanism of the Eastern Asia continental-margin and historical background of the evolution-movement of the crustobody are discussed. The pull-breaking-extending and thinning of the continental margin crustobody in the region result in the formation of the continental-margin extensional belt.Finally, the theoretical and practical significance of the study is pointed out. 展开更多
关键词 Historical-dynamic GEOTECTONICS the EASTERN Asia CONTINENTAL-MARGIN extensionAL BELT crustobody formation mechanism
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Oblique extension of pre-existing structures and its control on oil accumulation in eastern Bohai Sea 被引量:1
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作者 REN Jian LYU Dingyou +4 位作者 CHEN Xingpeng LIU Pengbo GUAN Dayong SU Kai ZHANG Hongguo 《Petroleum Exploration and Development》 2019年第3期553-564,共12页
Based on 3D seismic data, the evolution mechanism and characteristics of faults were investigated to reveal the structural origin and its control on differential hydrocarbon accumulation through comprehensive analyses... Based on 3D seismic data, the evolution mechanism and characteristics of faults were investigated to reveal the structural origin and its control on differential hydrocarbon accumulation through comprehensive analyses, including structure style analysis, fault activity analysis, analogue modelling and comparison among the wells. The complex fault system with differently trending faults resulted from strike-slip and rifting in Paleogene was partly activated, developed successively and stretched obliquely by the near-NS extensional stress field in Neogene. In the area little affected by pre-existing faults, new faults nearly perpendicular to the extension direction developed. The structural development in the study area was not caused by transpressional strike slip. Under the oblique extension effect of pre-existing faults, if the angle between the strike of pre-existing fault and the extensional direction is different, the strike-slip and extensional stresses are different in ratio. The larger the angle between the two is, the stronger the extensional component, the poorer the sealing ability of the fault, and the stronger the oil and gas migration capacity will be. Conversely, the smaller the angle between the two is, the stronger the strike-slip component, the better the sealing ability of the fault, and the poorer the oil and gas migration capacity will be. The accumulation condition analysis results considering the fault trend are in good agreement with the oil and gas shows in wells drilled in this area. 展开更多
关键词 OBLIQUE extension pre-existing faults STRIKE-SLIP COMPONENT extension COMPONENT PALEOGENE NEOGENE Bohai Sea
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Influence of low temperature on lethal time extension for different life stages of Cryptolestes ferrugineus (Stephens) with strong resistance to phosphine fumigation 被引量:2
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作者 Dianxuan Wang Judong Hou +1 位作者 Yilin Huang Jianhua Lyu 《Grain & Oil Science and Technology》 2020年第1期25-28,共4页
Knowing the time extension degree of full mortality in phosphine fumigation at low temperature significantly contributes to successful insect pest control,especially for reducing fumigation failure and inhibiting resi... Knowing the time extension degree of full mortality in phosphine fumigation at low temperature significantly contributes to successful insect pest control,especially for reducing fumigation failure and inhibiting resistance development.The comparison ofmortality and lethal time on eggs,larvae,pupae and adults of Cryptolestes ferrugineus(Stephens)was conducted,and the strain with 1043 times of resistance factor to phosphine was assayed during fumigation with 300 mL/m^3 of phosphine concentration at 18,23 and 28℃.The LT50 values to eggs,larvae,pupae and adults of C.ferrugineus at 18℃ were postponed by 2,2,1 and 5 d comparedwith that at 23℃,and 5,4,5 and 7 d compared with that at 28℃,respectively.The LT99 values to eggs,larvae,pupae and adults at 18℃ were 5,1,2 and 7 d longer than that at 23℃,and 6,5,5 and 10 d longer than that at 28℃,respectively.The lethal time of different life stages of the C.ferrugineus strain significantly increased with temperature decreasing.The exposure time of full mortality on pupae at 300 mL/m^3 of phosphine at 18℃ reached 38 d,which was 12 d longer than that of larvae.The order of tolerance of different life stages of C.ferrugineus exposed to 300 mL/m^3 phosphine from high to low was pupae,eggs,adults,larvae at tested temperatures. 展开更多
关键词 Cryptolestes ferrugineus PHOSPHINE STAGES Low temperature MORTALITY LETHAL TIME extension
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Development of extensional stresses in the compressional setting of the Himalayan thrust wedge: inference from numerical modelling 被引量:1
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作者 Ganesh Raj Joshi Daigoro Hayashi 《Natural Science》 2010年第7期667-680,共14页
The estimation of contemporary tectonic stress field and deformation in active fold-and-thrust belts are imperative in identifying active geodynamics and resulting faulting phenomenon. In this paper, we focus on conte... The estimation of contemporary tectonic stress field and deformation in active fold-and-thrust belts are imperative in identifying active geodynamics and resulting faulting phenomenon. In this paper, we focus on contemporary extensional tectonics in the overall compressive setting of the Himalayan orogen. Here we examine the regional tectonic stress field and upper crustal deformation in the Himalayan thrust wedge using a 2D finite element technique, incorporating elastic rheology under plain strain condition. The elastic models demonstrate that the extensional tectonic stress and related nor- mal faulting is extensively developed in the southern front of the Himalaya at shallow crustal level (&amp;lt;10 km in depth). Our modelling shows a good consistency with the geological field evidences of active faulting, focal mechanism solutions of medium size earthquakes in the several sectors of the Himalaya. Results based on numerical simulation, tectonic analysis and taking geological and geophysical data into account, we interpret that the present-day extensional tectonic activity is not restricted in the southern Tibet but distributed in the different sectors of the Himalayan fold-and-thrust belt co-exist with compressional structures. Modelling results also indicate that the nature, distribution and orientation of the maximum compressive stress (?1) of the Himalaya are mainly controlled by the intra crustal Main Himalayan d&amp;#233;collement (MHT). The significant amount of shear stress/strain concentration along the MHT in the western Nepal predict that the region is prone to moderate and great future earthquakes. 展开更多
关键词 extensionAL Stress Field CONVERGENT Displacement Finite Element Modelling HIMALAYAN WEDGE
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Diagnostic Study of an Extreme Explosive Cyclone over the Kuroshio/Kuroshio Extension Region 被引量:1
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作者 ZHANG Shuqin LIAO Qinghua +4 位作者 LIU Chunlei GAO Xiaoyu LONG Jingchao LI Pengyuan XU Jianjun 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期605-617,共13页
Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-Apr... Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-April)was studied to reveal the variations of the key factors at different explosive-developing stages.This EC had weak low-level baroclinicity,mid-level cyclonic-vorticity advection,and strong low-level water vapor convergence at the initial explosive-developing stage.The low-level baroclinicity and mid-level cyclonic-vorticity advection increased substantially during the maximum-deepening-rate stage.The diagnostic analyses using the Zwack-Okossi equation showed that diabatic heating was the main contributor to the initial rapid intensification of this EC.The cyclonic-vorticity advection and warm-air advection enhanced rapidly in the middle and upper troposphere and contributed to the maximum rapid intensification,whereas the diabatic heating weakened slightly in the mid-low troposphere.The relative contribution of the diabatic heating decreased from the initial explosive-developing stage to the maximum-deepening-rate stage due to the enhancement of other factors(the cyclonic-vorticity advection and warm-air advection).Furthermore,the physical factors contributing to this EC varied with the explosive-developing stage.The non-key factors at the initial explosive-developing stage need attention to forecast the rapid intensification. 展开更多
关键词 explosive cyclone diabatic heating cyclonic-vorticity advection rapid intensification the Kuroshio/Kuroshio extension region
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Origin of nucleation and growth of extension twins in grains unsuitably oriented for twinning during deformation of Mg-1%Al 被引量:1
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作者 Biaobiao Yang Javier LLorca 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1186-1203,共18页
A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded direction... A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded direction.The deformation mechanisms responsible for this behaviour were investigated through in-situ electron back-scattered diffraction,grain reference orientation deviation,and slip trace-modified lattice rotation.It was found that anomalous extension twins nucleated mainly at the onset of plastic deformation at or near grain boundary triple junctions.They were associated with the severe strain incompatibility between neighbour grains as a result from the differentbasal slip-induced lattice rotations.Moreover,the anomalous twins were able to grow with the applied strain due to the continuous activation ofbasal slip in different neighbour grains,which enhanced the strain incompatibility.These results reveal the complexity of the deformation mechanisms in Mg alloys at the local level when deformed along hard orientations. 展开更多
关键词 Magnesium extension twinning In-situ electron back-scattered diffraction basal slip Deformation mechanisms.
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THE SURFACE PATH OF THE KUROSHIO EXTENSION'S WESTERN SECTOR AND THE EDDIES ON BOTH SIDES
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作者 孙湘平 王元培 袁启科 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1989年第4期300-311,共12页
The surface path of the Kuroshio Extension’s western sector and the eddies on both sides are systematically analysed based on the GEK-measured surface current and temperature-salinity data from 1955-1985.The main res... The surface path of the Kuroshio Extension’s western sector and the eddies on both sides are systematically analysed based on the GEK-measured surface current and temperature-salinity data from 1955-1985.The main results are shown as follows : 1) According to the position and the features of distribution pattern, the surface path of the Kuroshio Extension’s western sector is classified into two kinds (straight and meander ) and seven types (f. ne, Sc, Ui or Vi,Vdi or Udi ,f+v). The straight kind accounts for 1/3 and the meander kind accounts for 2/3. 2) The warm eddies on the northern side originate mostly from the area off Sanriku and Joban of Japan. Their moving paths lie in two patterns: Pattern I, eddy moves northeastward or northward ; Pattern II. eddy rotates about the original area.The cold eddies on the southern side originate mainly from the area off Boso Peninsula. Their moving paths also lie in two patterns: Pattern III,eddy moves from west to east; Pattern IV.eddy moves from north to south. 展开更多
关键词 extension straight SALINITY NORTHWARD SURFACE originate SECTOR systematically mostly MOVES
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