期刊文献+
共找到1,864篇文章
< 1 2 94 >
每页显示 20 50 100
A phenomenological model for plastic flow behavior of rotating band material with a large temperature range
1
作者 Yi-cheng Zhu Jia-wei Fu +1 位作者 Lin-fang Qian Jing-hua Cao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期121-133,共13页
The plastic flow behavior of the rotating band material is investigated in this paper. The rotating band material is processed from H96 brass alloy, which is hardened to a much higher yield strength compared to the an... The plastic flow behavior of the rotating band material is investigated in this paper. The rotating band material is processed from H96 brass alloy, which is hardened to a much higher yield strength compared to the annealed one. The dynamically uniaxial compression behavior of the material is tested using the split Hopkinson pressure bar(SHPB) with temperature and strain rate ranging from 297 to 1073 K and500 to 3000 s^(-1), respectively, and a phenomenological plastic flow stress model is developed to describe the mechanical behavior of the material. The material is found to present noticeable temperature sensitivity and weak strain-rate sensitivity. The construction of the plastic flow stress model has two steps. Firstly, three univariate stress functions, taking plastic strain, plastic strain rate and temperature as independent variable, respectively, are proposed by fixing the other two variables. Then, as the three univariate functions describe the special cases of flow stress behavior under various conditions, the principle of stress compatibility is adopted to obtain the complete flow stress function. The numerical results show that the proposed plastic flow stress model is more suitable for the rotating band material than the existing well-known models. 展开更多
关键词 Rotating band Plastic flow behavior Large temperature range Phenomenological model
下载PDF
Optimal Parameter and Uncertainty Estimation of a Land Surface Model: Sensitivity to Parameter Ranges and Model Complexities 被引量:2
2
作者 YoulongXIA Zong-LiangYANG +1 位作者 PaulL.STOFFA MrinalK.SEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第1期142-157,共16页
Most previous land-surface model calibration studies have defined globalranges for their parameters to search for optimal parameter sets. Little work has been conducted tostudy the impacts of realistic versus global r... Most previous land-surface model calibration studies have defined globalranges for their parameters to search for optimal parameter sets. Little work has been conducted tostudy the impacts of realistic versus global ranges as well as model complexities on the calibrationand uncertainty estimates. The primary purpose of this paper is to investigate these impacts byemploying Bayesian Stochastic Inversion (BSI) to the Chameleon Surface Model (CHASM). The CHASM wasdesigned to explore the general aspects of land-surface energy balance representation within acommon modeling framework that can be run from a simple energy balance formulation to a complexmosaic type structure. The BSI is an uncertainty estimation technique based on Bayes theorem,importance sampling, and very fast simulated annealing. The model forcing data and surface flux datawere collected at seven sites representing a wide range of climate and vegetation conditions. Foreach site, four experiments were performed with simple and complex CHASM formulations as well asrealistic and global parameter ranges. Twenty eight experiments were conducted and 50 000 parametersets were used for each run. The results show that the use of global and realistic ranges givessimilar simulations for both modes for most sites, but the global ranges tend to produce someunreasonable optimal parameter values. Comparison of simple and complex modes shows that the simplemode has more parameters with unreasonable optimal values. Use of parameter ranges and modelcomplexities have significant impacts on frequency distribution of parameters, marginal posteriorprobability density functions, and estimates of uncertainty of simulated sensible and latent heatfluxes. Comparison between model complexity and parameter ranges shows that the former has moresignificant impacts on parameter and uncertainty estimations. 展开更多
关键词 optimal parameters uncertainty estimation CHASM model bayesian stochasticinversion parameter ranges model complexities
下载PDF
Discoloration Range and Shroud Image Depth Values Cannot Be Satisfied by the Same Proton Energy
3
作者 Giovanni Fazio 《Open Journal of Applied Sciences》 2023年第8期1224-1232,共9页
The radiative hypothesis has been revisited showing other characteristics, produced by the protons used as dyes in total disagree with the ones of the Body Image that appears on the Shroud of Turin. Our investigations... The radiative hypothesis has been revisited showing other characteristics, produced by the protons used as dyes in total disagree with the ones of the Body Image that appears on the Shroud of Turin. Our investigations highlight that for the protons to reach 3.7 cm in air, the distance that measures the range of discoloration effects, must be emitted with an energy of about 1.5 MeV using Wilson and Brobeck’s empirical formula and 1.35 MeV using Bethe’s. This last formula provides a result closer to reality. Bethe shows that the penetration depth is greater than that calculated empirically. Such a value of proton energy (1.35 MeV) makes it possible to satisfy the discoloration effects range for the Shroud but it is incompatible with a depth of penetration in linen that is only 200 nm. Moreover, using the same subatomic particles, we obtained on the colored linen a distribution of energy represented by regression but not linear. Thus, also the possible I(z) correlation, between color intensity and body-sheet distance, which should be due to the oxidizing action of protons, does not agree with that extracted from the Shroud of Turin. 展开更多
关键词 Shroud of Turin Body Image Formation Radiative Hypothesis Proton model Discoloration Effects range
下载PDF
Hybrid pedestrian positioning system using wearable inertial sensors and ultrasonic ranging
4
作者 Lin Qi Yu Liu +2 位作者 Chuanshun Gao Tao Feng Yue Yu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期327-338,共12页
Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,etc.The performance of traditional ... Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,etc.The performance of traditional PPS is limited by the cumulative error of inertial sensors,complex motion modes of pedestrians,and the low robustness of the multi-sensor collaboration structure.This paper presents a hybrid pedestrian positioning system using the combination of wearable inertial sensors and ultrasonic ranging(H-PPS).A robust two nodes integration structure is developed to adaptively combine the motion data acquired from the single waist-mounted and foot-mounted node,and enhanced by a novel ellipsoid constraint model.In addition,a deep-learning-based walking speed estimator is proposed by considering all the motion features provided by different nodes,which effectively reduces the cumulative error originating from inertial sensors.Finally,a comprehensive data and model dual-driven model is presented to effectively combine the motion data provided by different sensor nodes and walking speed estimator,and multi-level constraints are extracted to further improve the performance of the overall system.Experimental results indicate that the proposed H-PPS significantly improves the performance of the single PPS and outperforms existing algorithms in accuracy index under complex indoor scenarios. 展开更多
关键词 Pedestrian positioning system Wearable inertial sensors Ultrasonic ranging Deep-learning Data and model dual-driven
下载PDF
Design of scale model of plate-shaped absorber in a wide frequency range
5
作者 袁黎明 许勇刚 +2 位作者 高伟 戴飞 吴琪琳 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第4期299-304,共6页
In order to design the scale model in a wide frequency range,a method based on the reflective loss is proposed according to the high-frequency approximation algorithm,and an example of designing the scale model of a p... In order to design the scale model in a wide frequency range,a method based on the reflective loss is proposed according to the high-frequency approximation algorithm,and an example of designing the scale model of a plate-shaped absorber is given in this paper.In the example,the frequency of the full-size measurement ranges from 2.0 GHz to 2.4 GHz,the thickness of the full-size absorber is 1 mm and the scale ratio is 1/5.A two-layer scale absorber is obtained by the proposed method.The thickness values of the bottom and top layer are 0.4 mm and 0.5 mm,respectively.Furthermore,the scattering properties of a plate model and an SLICY model are studied by FEKO to verify the effectiveness of the designed scale absorber.Compared with the corresponding values from the theoretical scale model,the average values of the absolute deviations in 10 GHz~12 GHz are 0.53 d Bm^2,0.65 d Bm^2,0.76 d Bm^2 for the plate model and 0.20 d Bm^2,0.95 d Bm^2,0.77 d Bm^2 for the SLICY model while the incident angles are 0°,30°,and 60°,respectively.These deviations fall within the Radar cross section(RCS) measurement tolerance.Thus,the work in this paper has important theoretical and practical significance. 展开更多
关键词 scale model plate-shaped absorber wide frequency range RCS
下载PDF
Kinematics modeling of a 6-PSS parallel mechanism with wide-range flexure hinges 被引量:1
6
作者 杜志江 史若冲 董为 《Journal of Central South University》 SCIE EI CAS 2012年第9期2482-2487,共6页
A novel 6-PSS flexible parallel mechanism was presented,which employed wide-range flexure hinges as passive joints.The proposed mechanism features micron level positioning accuracy over cubic centimeter scale workspac... A novel 6-PSS flexible parallel mechanism was presented,which employed wide-range flexure hinges as passive joints.The proposed mechanism features micron level positioning accuracy over cubic centimeter scale workspace.A three-layer back-propagation(BP) neural network was utilized to the kinematics analysis,in which learning samples containing 1 280 groups of data based on stiffness-matrix method were used to train the BP model.The kinematics performance was accurately calculated by using the constructed BP model with 19 hidden nodes.Compared with the stiffness model,the simulation and numerical results validate that BP model can achieve millisecond level computation time and micron level calculation accuracy.The concept and approach outlined can be extended to a variety of applications. 展开更多
关键词 柔性铰链 宽范围 运动学建模 BP神经网络模型 并联机构 并行机制 计算精度 数值模拟
下载PDF
Numerical Modeling of Basin-Range Tectonics Related to Continent-Continent Collision 被引量:2
7
作者 CUIJunwen SHIJinsong +3 位作者 LIPengwu ZHANGXiaowei GUOXianpu DINGXiaozhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第1期24-35,共12页
Continent-continent collision is the most important driving mechanism for the occurrence of various geological processes in the continental lithosphere. How to recognize and determine continent-continent collision, es... Continent-continent collision is the most important driving mechanism for the occurrence of various geological processes in the continental lithosphere. How to recognize and determine continent-continent collision, especially its four-dimensional temporal-spatial evolution, is a subject that geological communities have long been concerned about and studied. Continent-continent collision is mainly manifested by strong underthrusting (subduction) of the underlying block along an intracontinental subduction zone and continuous obduction (thrusting propagation) of the overlying block along the intracontinental subduction zone, the occurrence of a basin-range tectonic framework in a direction perpendicular to the subduction zone and the flexure and disruption of the Moho. On the basis of numerical modeling, the authors discuss in detail the couplings between various amounts and rates of displacement caused by basin subsidence, mountain uplift and Moho updoming and downflexure during obduction (thrusting propagation) and subduction and the migration pattern of basin centers. They are probably indications or criteria for judgment or determination of continent-continent collision. 展开更多
关键词 continent-continent collision intracontinental subduction zone basin-range tectonics numerical modeling tectonic interface DISPLACEMENT
下载PDF
Effect of Modeling Range on Structural Analysis for Powerhouse of Hydroelectric Power Plant by FEM 被引量:1
8
作者 张启灵 伍鹤皋 杨华全 《Transactions of Tianjin University》 EI CAS 2009年第5期388-392,共5页
In this paper,three different modeling ranges were selected in the structural analysis for a hydropower house.The analysis was carried out using ABAQUS 6.6.The modeling range has a remarkable effect on finite element ... In this paper,three different modeling ranges were selected in the structural analysis for a hydropower house.The analysis was carried out using ABAQUS 6.6.The modeling range has a remarkable effect on finite element method(FEM) calculation result at the middle position of typical cross-sections where the concrete is relatively thin,and at the region close to turbine floor.If the ventilation barrel,floor slabs and columns above turbine floor are excluded from FEM model,the maximum rise difference of pedestal structure increases by about 24% compared with that of the whole model.It is indicated that different modeling ranges indeed affect FEM calculation result,and the structure above turbine floor in the FEM model should be included. 展开更多
关键词 有限元分析 厂房结构 水电站 建模 有限元模型 ABAQUS 计算结果 有限元方法
下载PDF
The ‘Two oceans and one sea' extended range numerical prediction system with an ultra-high resolution atmosphere-ocean-land regional coupled model 被引量:2
9
作者 Zhang Shao-Qing Yang LIU +4 位作者 Ma Xiao-Hui Wang Hong-Na Zhang Xue-Feng Yu Xiao-Lin Lu Lv 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第4期364-371,共8页
‘两洋一海’区域是‘21世纪海上丝绸之路’的重要空间载体,也是国防安全的核心战略海区。随着社会需求加剧,介于常规短期和气候尺度之间的延伸期(10–30天)预测的重要性逐渐突显。受限于海洋短期预报不含大气海洋快慢过程转化的信息存... ‘两洋一海’区域是‘21世纪海上丝绸之路’的重要空间载体,也是国防安全的核心战略海区。随着社会需求加剧,介于常规短期和气候尺度之间的延伸期(10–30天)预测的重要性逐渐突显。受限于海洋短期预报不含大气海洋快慢过程转化的信息存储机制、大气高频变化制约预报时效、全球气候预报分辨率较低、气陆海多圈层耦合机制理解不足及区域预报无较好初始化等问题,我国海洋延伸期预测工作仍是盲点,导致对一些海洋过程、灾害事件无法做出模拟及预警。本文将介绍基于区域超高分辨率多圈层耦合模型的两洋一海区域延伸期数值预测系统研制情况,包括研究内容,技术方案,创新和预期成果等。 展开更多
关键词 数值预报系统 超高分辨率 多圈层耦合模型 延伸期期预报
下载PDF
CROSS-RANGE RESOLUTION OF SYNTHETIC APERTURE RADAR BASED ON DIVING MODEL 被引量:1
10
作者 Sun Bing Zhou Yinqing Chen Jie 《Journal of Electronics(China)》 2011年第1期71-76,共6页
This paper concentrates on the cross-range resolution of Synthetic Aperture Radar(SAR) based on diving model.In comparison to the azimuth resolution,the cross-range resolution can manifest the two-dimensional resoluti... This paper concentrates on the cross-range resolution of Synthetic Aperture Radar(SAR) based on diving model.In comparison to the azimuth resolution,the cross-range resolution can manifest the two-dimensional resolution ability of the imaging sensor SAR correctly.The diving model of SAR is an extended model from the conventional stripmap model,and the cross-range resolution expression is deduced from the equivalent linear frequency modulation pulses' compression.This expression points out that only the cross-range velocity component of the horizontal velocity contributes to the cross-range resolution.Also the cross-range resolution expressions and the performance of the conventional stripmap operation,squint side-look operation and beam circular-scanning operation are discussed.The cross-range resolution expression based on diving model will provide more general and more accurate reference. 展开更多
关键词 Synthetic Aperture Radar(SAR) Cross-range resolution Diving model Velocity component
下载PDF
Method of Dynamic VaR and CVaR Risk Measures Forecasting for Long Range Dependent Time Series on the Base of the Heteroscedastic Model
11
作者 Nataliya D. Pankratova Nataliia G. Zrazhevska 《Intelligent Control and Automation》 2017年第2期126-138,共13页
The paper proposes a new method of dynamic VaR and CVaR risk measures forecasting. The method is designed for obtaining the forecast estimates of risk measures for volatile time series with long range dependence. The ... The paper proposes a new method of dynamic VaR and CVaR risk measures forecasting. The method is designed for obtaining the forecast estimates of risk measures for volatile time series with long range dependence. The method is based on the heteroskedastic time series model. The FIGARCH model is used for volatility modeling and forecasting. The model is reduced to the AR model of infinite order. The reduced system of Yule-Walker equations is solved to find the autoregression coefficients. The regression equation for the autocorrelation function based on the definition of a long-range dependence is used to get the autocorrelation estimates. An optimization procedure is proposed to specify the estimates of autocorrelation coefficients. The procedure for obtaining of the forecast values of dynamic risk measures VaR and CVaR is formalized as a multi-step algorithm. The algorithm includes the following steps: autoregression forecasting, innovation highlighting, obtaining of the assessments for static risk measures for residuals of the model, forming of the final forecast using the proposed formulas, quality analysis of the results. The proposed method is applied to the time series of the index of the Tokyo stock exchange. The quality analysis using various tests is conducted and confirmed the high quality of the obtained estimates. 展开更多
关键词 DYNAMIC VaR CVAR Forecasting Long range DEPENDENCE Hurst PARAMETER Heteroscedastic model
下载PDF
A privacy-preserved indexing schema in DaaS model for range queries
12
作者 郝任之 Li Jun Wu Guangjun 《High Technology Letters》 EI CAS 2020年第4期448-454,共7页
In a database-as-a-service(DaaS)model,a data owner stores data in a database server of a service provider,and the DaaS adopts the encryption for data privacy and indexing for data query.However,an attacker can obtain ... In a database-as-a-service(DaaS)model,a data owner stores data in a database server of a service provider,and the DaaS adopts the encryption for data privacy and indexing for data query.However,an attacker can obtain original data’s statistical information and distribution via the indexing distribution from the database of the service provider.In this work,a novel indexing schema is proposed to satisfy privacy-preserved data management requirements,in which an attacker cannot obtain data source distribution or statistic information from the index.The approach includes 2 parts:the Hash-based indexing for encrypted data and correctness verification for range queries.The evaluation results demonstrate that the approach can hide statistical information of encrypted data distribution while can also obtain correct answers for range queries.Meanwhile,the approach can achieve nearly 10 times and 35 times improvement on encrypted data publishing and indexing respectively,compared with the start-of-the-art method order-preserving Hash-based function(OPHF). 展开更多
关键词 database-as-a-service(DaaS)model data privacy and security data verification range query
下载PDF
SOUTH CHINA REGIONAL SHORT RANGE CLIMATE PREDICTION MODEL AND ITS PERFORMANCE
13
作者 闫敬华 《Journal of Tropical Meteorology》 SCIE 2000年第2期162-171,共10页
In this paper, a newly established "South China Regional Short Range Climate Prediction Model System" is introduced and its performance is analyzed in real case simulation. It shows that the system has a goo... In this paper, a newly established "South China Regional Short Range Climate Prediction Model System" is introduced and its performance is analyzed in real case simulation. It shows that the system has a good performance and suitable for short range climate modeling. The model simulates well the monthly mean, pentad mean and daily field, pentad mean and daily field and can depict more details than coarse resolution analyses. Weather systems and information can pass into and out of the model domain through lateral boundaries without notable damping. Almost all of the weather and climate changes can be reflected in the simulation, in which both the changing tendencies, amplitudes, speeds, and phases are consistent with the real cases. The simulated precipitation is much close to the observed one, both in the extent, position and in the intensity of rainfall. In addition, some smaller precipitation centers could also be reflected in the simulation. 展开更多
关键词 REGIONAL SHORT-range CLIMATE model REAL CASE SIMULATION performan
下载PDF
Application and Verification of Multi-Model Products in Medium Range Forecast
14
作者 Rong Yao Zhiming Kang +1 位作者 Yong Li Xiangning Cai 《Journal of Geoscience and Environment Protection》 2018年第7期178-193,共16页
The verification analysis is applied to medium-range forecast products of T639, ECMWF, Japan model, NCEP ensemble forecast and NMC multi-model integration in late October 2012. The results show that ECMWF model has ob... The verification analysis is applied to medium-range forecast products of T639, ECMWF, Japan model, NCEP ensemble forecast and NMC multi-model integration in late October 2012. The results show that ECMWF model has obvious advantage over other models in terms of height field and precipitation forecast;the westerly-wind index, geostrophic U wind and 850 hPa temperature prediction products can reflect the adjustment of atmospheric circulation and the activity of cold air, which have a good reference for the medium-range temperature forecast in the eastern China;the prediction of ECMWF height field and wind field can well grasp the main weather processes within 192 h, but beyond 192 h the model forecast ability decreases significantly;different models have large deviations in the medium-range forecast of typhoon track and the intensity and range of typhoon precipitation. 展开更多
关键词 model VERIFICATION Medium-range FORECAST Deviation
下载PDF
A TIME FILTERING SCHEME FOR THE SHORT RANGE CLIMATE PREDICTION MODEL PRODUCTS AND ITS REAL CASE ANALYSIS
15
作者 闫敬华 《Journal of Tropical Meteorology》 SCIE 2000年第1期29-36,共7页
A filtering / extracting scheme for various timescale processes in short range climate model out-put is established by using the scale scattering method. And the climatological meanings as well as the impor-tance of t... A filtering / extracting scheme for various timescale processes in short range climate model out-put is established by using the scale scattering method. And the climatological meanings as well as the impor-tance of the filtered series are discussed. In the latter part of work, the effectiveness of the filtering method and the performance of the prediction model are analyzed through a real case. 展开更多
关键词 PRODUCTS of SHORT-range CLIMATE model scale FILTERING SCHEME factors describing the predicted cli-mate performance of model
下载PDF
Model-Based Split-Range Algorithm for the Temperature Control of a Batch Reactor
16
作者 Miklós Gábor Balaton Lajos Nagy Ferenc Szeifert 《Engineering(科研)》 2012年第9期515-525,共11页
In the manufacturing processes of high value-added products in the pharmaceutical, fine chemical polymer and food industry, insufficient control might produce off-grade products. This can cause significant financial l... In the manufacturing processes of high value-added products in the pharmaceutical, fine chemical polymer and food industry, insufficient control might produce off-grade products. This can cause significant financial losses, or in the pharmaceutical industry, it can result in an unusable batch. In these industries, batch reactors are commonly used, the control of which is essentially a problem of temperature control. In the industry, an increasing number of heating-cooling systems utilising three different temperature levels can be found, which are advantageous from an economic point of view. However, it makes the control more complicated. This paper presents a split-range designing technique using the model of the controlled system with the aim to design a split-range algorithm more specific to the actual sys- tem. The algorithm described provides high control performance when using it with classical PID-based cascade temperature control of jacketed batch reactors;however, it can be used with or as part of other types of controllers, for ex- ample, model-based temperature controllers. The algorithm can be used in the case of systems where only two as well as where three temperature levels are used for temperature control. Besides the switching between the modes of opera- tion and calculating the value of the manipulated variable, one of the most important functions of the split-range algo- rithm is to keep the sign of the gain of the controlled system unchanged. However, with a more system-specific split-range solution, not only can the sign of the gain be kept unchanged, but the gain can also be constant or less de- pendent on the state of the system. Using this solution, the design of the PID controller becomes simpler and can be implemented in existing systems without serious changes. 展开更多
关键词 BATCH REACTOR model-BASED CONTROL Split-range Monofluid Thermoblock Temperature CONTROL
下载PDF
蒙特卡罗法在化感作用全区间抑制强度评估(wholerange assessment)中的应用
17
作者 刘迎湖 付银莲 +2 位作者 陈小秋 安民 陈实 《生态科学》 CSCD 2009年第4期357-361,共5页
植物化感作用的强弱与化感物质的作用浓度相关。化感作用全区间抑制强度指数(Whole-range assessmentindex)是用于评估植物在一定的化感物质作用范围内所受化感作用总体抑制程度的一种方法。在对非线性剂量响应进行曲线拟合的基础上,本... 植物化感作用的强弱与化感物质的作用浓度相关。化感作用全区间抑制强度指数(Whole-range assessmentindex)是用于评估植物在一定的化感物质作用范围内所受化感作用总体抑制程度的一种方法。在对非线性剂量响应进行曲线拟合的基础上,本研究应用蒙特卡罗模拟法为计算化感作用全区间抑制强度指数提供了一种科学的数学计算方法,并应用该计算方法分析了番茄水浸提液对生菜、萝卜、白菜、菜心、包心菜、豆角和水稻的化感作用强度。 展开更多
关键词 化感作用 低促高抑(赫米斯Hormesis) 化感作用全区间抑制强度指数(whole-range assessment index) An.Johnson.Lover Hormesis模型 蒙特卡罗模拟法(Monte Carlo simulation)
下载PDF
Late Mesozoic Thermotectonic Evolution of the Jueluotage Range,Eastern Xinjiang,Northwest China:Evidence from Apatite Fission Track Data 被引量:4
18
作者 ZHU Wenbin WAN Jinglin +5 位作者 SHU Liangshu ZHANG Zhiyong SU Jinbao SUN Yah GUO Jichun ZHANG Xueyun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第2期348-357,共10页
Although many authors have emphasized the Cenozoic history of deformation, exhumation and cooling in the Tiaushan area related to the India-Asia collision, very little is known about the Mesozoic history of compressio... Although many authors have emphasized the Cenozoic history of deformation, exhumation and cooling in the Tiaushan area related to the India-Asia collision, very little is known about the Mesozoic history of compression and uplift within the Tianshan. In order to obtain information about the Mesozoic exhumation history and processes of cooling in eastern Tianshan, fission track methods on apatite were used. Sampling was made in the Jueluotage Range. Three samples (Z001-Z003) were taken from granite in borehole ZK6301 of Yandong pluton; the ages range from 97.0 to 87.6 Ma that are much younger than the pluton age which was dated by U-Pb zircon at 334±2 Ma. Two samples in northern piedmont of the Jueluotage Range were collected from Jurassic strata in Dikaner (DK001) and Dananhu (D001) whose ages are 91.5 and 93.4 Ma respectively. The average apparent exhumation rate is 0.039 nun/a calculated by extrapolation on the basis of Yandong samples, indicating an extremely slow exhumation in the Jueluotage Range since the Late Cretaceous. Two Jurassic samples reached the maximum depths after deposition and experienced the maximum temperatures of ca. 105 and 108℃ until the late Early Cretaceous before a period of cooling and exhumation occurred at 114 and 106 Ma. 展开更多
关键词 Jueluotage range APATITE fission track EXHUMATION cooling thermal modeling XINJIANG
下载PDF
Respective Roles of Short-and Long-Range Interactions in Protein Folding 被引量:3
19
作者 WANGLong-hui HUMin +1 位作者 ZHOUHuai-bei LIUJuan 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第6期962-966,共5页
A new method was presented to discuss the respective roles of short- and long-range interactions in protein folding. It's based on an off-lattice model, which is also being called as toy model. Simulated annealing... A new method was presented to discuss the respective roles of short- and long-range interactions in protein folding. It's based on an off-lattice model, which is also being called as toy model. Simulated annealing algorithm was used to search its native conformation. When it is applied to analysis proteins 1agt and 1aho, we find that helical segment cannot fold into native conformation without the influence of long-range interactions. That's to say that long-range interactions are the main determinants in protein folding. Key words toy model - protein folding - simulated annealing algorithm - short and long range interactions CLC number O 242.28 - Q71 Foundation item: Supported by the National Natural Science Foundation of China((60301009)Biography: WANG Long-hui (1976-), female, Ph. D candidate, research direction: machine learning, bioinformatics. 展开更多
关键词 toy model protein folding simulated annealing algorithm short and long range interactions
下载PDF
Prediction of Streamwise Flow-Induced Vibration of A Circular Cylinder in the First Instability Range 被引量:2
20
作者 徐万海 余建星 +2 位作者 杜杰 成安康 康昊 《China Ocean Engineering》 SCIE EI 2012年第4期555-564,共10页
The streamwise flow-induced vibration of a circular cylinder with symmetric vortex shedding in the first instability range is investigated, and a wake oscillator model for the dynamic response prediction is proposed. ... The streamwise flow-induced vibration of a circular cylinder with symmetric vortex shedding in the first instability range is investigated, and a wake oscillator model for the dynamic response prediction is proposed. An approach is applied to calibrate the empirical parameters in the present model; the numerical and experimental results are compared to validate the proposed model. It can be found that the present prediction model is accurate and sufficiently simple to be easily applied in practice. 展开更多
关键词 streamwise flow-induced vibrations circular cylinder wake oscillator model first instability range
下载PDF
上一页 1 2 94 下一页 到第
使用帮助 返回顶部