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A Neural-network-based Alternative Scheme to Include Nonhydrostatic Processes in an Atmospheric Dynamical Core
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作者 Yang XIA Bin WANG +13 位作者 Lijuan LI Li LIU Jianghao LI Li DONG Shiming XU Yiyuan LI Wenwen XIA Wenyu HUANG Juanjuan LIU Yong WANG Hongbo LIU Ye PU Yujun HE Kun XIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1083-1099,I0002,I0003,共19页
Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostat... Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostatic solver in an atmospheric dynamical core.The NAS is designed to replace this solver,which can be incorporated into any hydrostatic models so that existing well-developed hydrostatic models can effectively serve for a longer time.Recent advances in machine learning(ML)provide a potential tool for capturing the main complicated nonlinear-nonhydrostatic relationship.In this study,an ML approach called a neural network(NN)was adopted to select leading input features and develop the NAS.The NNs were trained and evaluated with 12-day simulation results of dry baroclinic-wave tests by the Weather Research and Forecasting(WRF)model.The forward time difference of the nonhydrostatic tendency was used as the target variable,and the five selected features were the nonhydrostatic tendency at the last time step,and four hydrostatic variables at the current step including geopotential height,pressure in two different forms,and potential temperature,respectively.Finally,a practical NAS was developed with these features and trained layer by layer at a 20-km horizontal resolution,which can accurately reproduce the temporal variation and vertical distribution of the nonhydrostatic tendency.Corrected by the NN-based NAS,the improved hydrostatic solver at different horizontal resolutions can run stably for at least one month and effectively reduce most of the nonhydrostatic errors in terms of system bias,anomaly root-mean-square error,and the error of the wave spatial pattern,which proves the feasibility and superiority of this scheme. 展开更多
关键词 neural network nonhydrostatic alternative scheme atmospheric model dynamical core
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Estimation of free core nutation parameters and availability of computing options
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作者 Weiwei Yang Xiaoming Cui +2 位作者 Jianqiao Xu Qingchao Liu Ming Qin 《Geodesy and Geodynamics》 EI CSCD 2024年第1期61-74,共14页
The Earth’s Free Core Nutation(FCN) causes Earth tides and forced nutation with frequencies close to the FCN that exhibit resonance effects.High-precision superconducting gravimeter(SG) and very long baseline interfe... The Earth’s Free Core Nutation(FCN) causes Earth tides and forced nutation with frequencies close to the FCN that exhibit resonance effects.High-precision superconducting gravimeter(SG) and very long baseline interferometry(VLBI) provide good observation techniques for detecting the FCN parameters.However,some choices in data processing and solution procedures increase the uncertainty of the FCN parameters.In this study,we analyzed the differences and the effectiveness of weight function and ocean tide corrections in the FCN parameter detection using synthetic data,SG data from thirty-one stations,and the 10 celestial pole offset(CPO) series.The results show that significant discrepancies are caused by different computing options for a single SG station.The stacking method,which results in a variation of0.24-5 sidereal days(SDs) in the FCN period(T) and 10^(3)-10^(4) in the quality factor(Q) due to the selection of the weighting function and the ocean tide model(OTM),can effectively suppress this influence.The statistical analysis results of synthetic data shows that although different weight choices,while adjusting the proportion of diurnal tidal waves involved,do not significantly improve the accuracy of fitted FCN parameters from gravity observations.The study evaluated a series of OTMs using the loading correction efficiency.The fitting of FCN parameters can be improved by selecting the mean of appropriate OTMs based on the evaluation results.Through the estimation of the FCN parameters based on the forced nutation,it was found that the weight function P_(1) is more suitable than others,and different CPO series(after 2009) resulted in a difference of 0.4 SDs in the T and of 103 in the Q.We estimated the FCN parameters for SG(T=430.4±1.5 SDs and Q=1.52×10^(4)±2.5×10^(3)) and for VLBI(T=429.8±0.7 SDs,Q=1.88×10^(4)±2.1×10^(3)). 展开更多
关键词 Free core nutation Superconducting gravimeter Very long baseline interferometry Weight function Ocean tide model
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Studies on Melt Spinning of Sheath-Core Bicomponent Fibers: Fundamental Equations on the Dynamics of Melt Spinning
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作者 Yang Chongchang(杨崇倡) +1 位作者 Wang Huaping(王华平) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第2期37-40,共4页
An attempt was made to numerically compute the temperature profile within the melt spinning of sheath core bicomponent fibers by deriving a set of simultaneous partial differential equations. The effects of accelerati... An attempt was made to numerically compute the temperature profile within the melt spinning of sheath core bicomponent fibers by deriving a set of simultaneous partial differential equations. The effects of acceleration, gravity, and air friction on the kinetics of the polymer were included and the upper-convected Maxwell model as the constitutive equation was adopted in this model.The sheath- core bicomponent fibers were partitioned intb a serial of circular cross section and it is assumed that each circular cross section has a temperature gradient while conducting the equation of energy balance. A mathematical model was developed to describe the melt spinning of sheath-core bicomponent fibers. 展开更多
关键词 MELT spinning sheath-core bicomponent fibers mathematical model NUMERICAL simulation
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Dynamic and electrical responses of a curved sandwich beam with glass reinforced laminate layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact
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作者 N.SHAHVEISI S.FELI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期155-178,共24页
The dynamic responses and generated voltage in a curved sandwich beam with glass reinforced laminate(GRL)layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact(LVI)are investigate... The dynamic responses and generated voltage in a curved sandwich beam with glass reinforced laminate(GRL)layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact(LVI)are investigated.The current study aims to carry out a dynamic analysis on the sandwich beam when the impactor hits the top face sheet with an initial velocity.For the layer analysis,the high-order shear deformation theory(HSDT)and Frostig's second model for the displacement fields of the core layer are used.The classical non-adhesive elastic contact theory and Hunter's principle are used to calculate the dynamic responses in terms of time.In order to validate the analytical method,the outcomes of the current investigation are compared with those gained by the experimental tests carried out by other researchers for a rectangular composite plate subject to the LVI.Finite element(FE)simulations are conducted by means of the ABAQUS software.The effects of the parameters such as foam modulus,layer material,fiber angle,impactor mass,and its velocity on the generated voltage are reviewed. 展开更多
关键词 analytical model piezoelectric layer curved sandwich beam glass reinforced laminate(GRL) pliable core low-velocity impact(LVI) classical non-adhesive elastic contact theory
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Parental Psychological Control and Internet Gaming Disorder Tendency:A Moderated Mediation Model of Core Self-Evaluation and Intentional Self-Regulation
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作者 Zhiqiao Ji Shuhua Wei Hejuan Ding 《International Journal of Mental Health Promotion》 2024年第7期547-558,共12页
Internet gaming disorder(IGD)among junior high school students is an increasingly prominent mental health concern.It is important to look for influences behind internet gaming disorder tendency(IGDT)in the junior high... Internet gaming disorder(IGD)among junior high school students is an increasingly prominent mental health concern.It is important to look for influences behind internet gaming disorder tendency(IGDT)in the junior high school student population.The present study aimed to reveal the explanatory mechanisms underlying the association between parental psychological control(PPC)and internet gaming disorder tendency among junior high school students by testing the mediating role of core self-evaluation(CSE)and the moderating role of intentional self-regulation(ISR).Participants in present study were 735 Chinese junior high school students who completed offline self-report questionnaires on parental psychological control,core self-evaluation,intentional self-regulation,and Internet gaming disorder tendency.Analyses were conducted via mediation and moderated mediation.The results showed that:(1)Parental psychological control was positively related to junior high school students’Internet gaming disorder tendency.Core self-evaluation,and intentional self-regulation were negatively related to junior high school students’Internet gaming disorder tendency,respectively.(2)Core self-evaluation partially mediated the relationship between parental psychological control and junior high school students’Internet gaming disorder tendency.(3)Intentional self-regulation moderated the association between parental psychological control and Internet gaming disorder tendency,as well as the relationships between parental psychological control and core self-evaluation and core self-evaluation and Internet gaming disorder tendency in the mediated model.Based on these findings,we believe that there is a need to weaken parental psychological control,strengthen junior high school students’core self-evaluation and intentional self-regulation,and to recognize the important role of parents as well as their children’s personal positive traits in the healthy development of junior high school students. 展开更多
关键词 Internet gaming disorder tendency parental psychological control core self-evaluation intentional self-regulation moderated mediation model junior high school students
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Analysis on the Core Competitiveness of Rice Seed Industry in Guangxi Province Based on Diamond Model
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作者 张晓丽 薛艳霞 +6 位作者 吕荣华 王强 陈雷 唐茂艳 陶伟 高国庆 梁天锋 《Agricultural Science & Technology》 CAS 2016年第8期1963-1967,1977,共6页
By using diamond model, the current development status and core competitiveness of the rice seed industry in Guangxi Province were analyzed in detail from the 6 aspects of production factors, demand factors, related i... By using diamond model, the current development status and core competitiveness of the rice seed industry in Guangxi Province were analyzed in detail from the 6 aspects of production factors, demand factors, related industries and support industries, firm strategy, chance factor and government factor, which clarified the advantages of the rice seed industry of Guangxi in the nature and technological factors, firm strategy and government policy, and the disadvantages in demand factors, production cost, infrastructure and related industries. And the corresponding countermeasures were proposed to enhance the competitiveness of the rice seed industry of Guangxi. 展开更多
关键词 Diamond model RICE core competitiveness GUANGXI
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Fedore Core 4.0下WRF模式系统的配置安装及运行 被引量:2
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作者 邱明宇 林建兴 王尚荣 《气象研究与应用》 2007年第4期39-42,共4页
介绍操作系统平台为Fedore Core 4.0下,WRF模式的安装和运行。重点介绍了PGI6.16编译器的配置、Fedore Core 4.0的配置和WRF模式的多重嵌套及其运行步骤的关键设置。
关键词 WRF模式 PGI编译器 Fedore core 4.0系统
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基于CORE模型的古街文旅体验产品设计 被引量:1
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作者 徐建 《包装工程》 CAS 北大核心 2023年第24期483-491,共9页
目的 古街需要形成浓郁的人文氛围和商业环境,通过开发具有优良体验感的文旅产品,为现有文旅产品增加更多互动体验的环节。这不仅可以让游客充分感受古街的地域特色,增强出行动机,也可以使游客有节奏地体验到古街文旅产品中传达的信息,... 目的 古街需要形成浓郁的人文氛围和商业环境,通过开发具有优良体验感的文旅产品,为现有文旅产品增加更多互动体验的环节。这不仅可以让游客充分感受古街的地域特色,增强出行动机,也可以使游客有节奏地体验到古街文旅产品中传达的信息,从而对产品体验形成获得感、满足感、认同感等感受,以促进古街文旅产业发展。方法 基于CORE模型,采用观察法、文献研究法、探索性研究法收集当下古街文旅产品体验的趣味点,结合头脑思维风暴,借鉴游戏、玩具、劳动实践中体验感好的部分,组织设计行动及体验活动,重视产品体验心理过程的反馈。结果 设计创新性体验产品及体验流程,通过李克特量表及Kano模型对产品方案进行评估。结论 在设计新产品时,重点展现文旅产品的趣味体验,对在售产品提供体验活动思路及行动方案,从而提升游客对地域特色文化的感受力。 展开更多
关键词 文旅产品 体验 core模型 古街
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Assessment on Evaluating Parameters of Rice Core Collections Constructed by Genotypic Values and Molecular Marker Information 被引量:17
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作者 WANG Jian-cheng HU Jin +1 位作者 ZHANG Cai-fang ZHANG Sheng 《Rice science》 SCIE 2007年第2期101-110,共10页
Eleven evaluating parameters for rice core collection were assessed based on genotypic values and molecular marke' information. Monte Carlo simulation combined with mixed linear model was used to eliminate the interf... Eleven evaluating parameters for rice core collection were assessed based on genotypic values and molecular marke' information. Monte Carlo simulation combined with mixed linear model was used to eliminate the interference from environment in order to draw more reliable results. The coincidence rate of range (CR) was the optimal parameter. Mean Simpson index (MD), mean Shannon-Weaver index of genetic diversity (M1) and mean polymorphism information content (MPIC) were important evaluating parameters. The variable rate of coefficient of variation (VR) could act as an important reference parameter for evaluating the variation degree of core collection. Percentage of polymorphic loci (p) could be used as a determination parameter for the size of core collection. Mean difference percentage (MD) was a determination parameter for the reliability judgment of core collection. The effective evaluating parameters for core collection selected in the research could be used as criteria for sampling percentage in different plant germplasm populations. 展开更多
关键词 core collection genotypic value molecular marker information Monte Carlo simulation mixed linear model evaluating parameter RICE
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The expression of core fucosylated E-cadherin in cancer cells and lung cancer patients: prognostic implications 被引量:19
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作者 FeiGENG BiZhiSHI +1 位作者 YunFengYUAN XingZhongWU 《Cell Research》 SCIE CAS CSCD 2004年第5期423-433,共11页
It is well documented that the glycosylation of E-cadherin is correlated with cancer metastasis, but whether E- cadherin could be core fucosylated remains largely unknown. We found that E-cadherin was core fucosylated... It is well documented that the glycosylation of E-cadherin is correlated with cancer metastasis, but whether E- cadherin could be core fucosylated remains largely unknown. We found that E-cadherin was core fucosylated in highly metastatic lung cancer cells while absent in lowly metastatic lung cancer cells. Since α-1,6 Fucosyltransferase (α-1,6 FucT) is known to catalyze the reaction of core fucosylation, we investigated the biological function of core fucosylation on E-cadherin by α-1,6 FucT targeted RNAi and transfecting α-1,6 FucT expression vector. As a result, calcium dependent cell-cell adhesion mediated by E-cadherin was strengthened with the reduction of core fucosylation on E- cadherin after RNAi and was weakened with the elevated core fucosylation on E-cadherin after α-1,6 FucT over expression. Our data indicated that α-1,6 FucT could regulate E-cadherin mediated cell adhesion and thus play an important role in cancer development and progression. Computer modeling showed that core fucosylation on E-cadherin could significantly impair three-dimensional conformation of N-glycan on E-cadherin and produce conformational asym- metry so as to suppress the function of E-cadherin. Furthermore, the relationship between the expression of core fucosylated E-cadherin and clinicopathological background of lung cancer patients was explored in lung cancer tissue of patients. It turns out to demonstrate that core fucosylated E-cadherin could serve as a promising prognostic indicator for lung cancer patients. 展开更多
关键词 core fucosylated E-cadherin PROGNOSIS cancer metastasis RNA interference molecular modeling.
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APPLICATION OF THE SHRINKING CORE MODEL TO THE KINETICS OF ZINC OXIDE DESULFURIZATION 被引量:3
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作者 李彦旭 张栓兵 +1 位作者 郭汉贤 钟炳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1997年第4期14-21,共8页
The kinetics of H<sub>2</sub>S removal by zinc oxide desulfurizer was studied through thermogravimetricanalysis.The experimental results show that desulfurization rate was controlled,at high temperatureand... The kinetics of H<sub>2</sub>S removal by zinc oxide desulfurizer was studied through thermogravimetricanalysis.The experimental results show that desulfurization rate was controlled,at high temperatureand low conversion,by the chemical reaction rate,and at low temperature and high conversion by thegrain diffusion rate.The reaction is first order with respect to H<sub>2</sub>S concentration in the differentcontrolled stages.The kinetic behavior can be modeled through the employment of the shrinking coremodel.The values of the model parameters were determined.The variation tendencies with temperatureand concentration of H<sub>2</sub>S at the controlled stages were discussed. 展开更多
关键词 hydrogen SULFIDE DESULFURIZATION KINETICS SHRINKING core model
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The Selection and Breeding of a Novel Microorganism Strain I and Investigation of Core Model Experiment for MEOR 被引量:4
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作者 ZhangZhongzhi WeiXiaofang LuoYijing LiQingzhong LeiGuanglun 《Petroleum Science》 SCIE CAS CSCD 2005年第2期95-102,共8页
This paper introduces the results of selecting and breeding a micro-organism, Strain I, and its core model experiment investigation for microbial enhanced oil recovery (MEOR). Strain I was separated from the formation... This paper introduces the results of selecting and breeding a micro-organism, Strain I, and its core model experiment investigation for microbial enhanced oil recovery (MEOR). Strain I was separated from the formation water of the Dagang oil field, with analytical results showing that Strain I is a gram-positive bacillus. A further study revealed that this strain has an excellent tolerance of environmental stresses: It can survive in conditions of 70℃, 30 wt% salinity and pH3.5-9.4. Strain I can metabolize biosurfactants that could increase the oil recovery ratio, use crude oil as the single carbon source, and decompose long-chain paraffin with a large molecular weight into short-chain paraffin with a small molecular weight. The core model experiment shows that Strain I enhances oil recovery well. Using 2 vol% of the fermentation solution of Strain I to displace the crude oil in the synthetic plastic bonding core could increase the recovery ratio by 21.6%. 展开更多
关键词 BIOSURFACTANT THERMOTOLERANCE salinity tolerance core model flooding experiment microbial enhanced oil recovery.
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Mathematical simulation of hot metal desulfurization during KR process coupled with an unreacted core model 被引量:8
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作者 Yanyu Zhao Wei Chen +1 位作者 Shusen Cheng Lifeng Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第4期758-766,共9页
A three-dimensional mathematical model was established to predict the multiphase flow,motion and dispersion of desulfurizer particles,and desulfurization of hot metal during the Kanbara reactor(KR)process.The turbulen... A three-dimensional mathematical model was established to predict the multiphase flow,motion and dispersion of desulfurizer particles,and desulfurization of hot metal during the Kanbara reactor(KR)process.The turbulent kinetic energy-turbulent dissipation rate(k-ε)turbulence model,volume-of-fluid multiphase model,discrete-phase model,and unreacted core model for the reaction between the hot metal and particles were coupled.The measured sulfur content of the hot metal with time during the actual KR process was employed to validate the current mathematical model.The distance from the lowest point of the liquid level to the bottom of the ladle decreased from 3170 to2191 mm when the rotation speed increased from 30 to 110 r/min,which had a great effect on the dispersion of desulfurizer particles.The critical rotation speed for the vortex to reach the upper edge of the stirring impeller was 70 r/min when the immersion depth was 1500 mm.The desulfurization rate increased with the increase in the impeller rotation speed,whereas the influence of the immersion depth was relatively small.Formulas for different rotation parameters on the desulfurization rate constant and turbulent energy dissipation rate were proposed to evaluate the variation in sulfur content over time. 展开更多
关键词 DESULFURIZATION unreacted core model desulfurizer dispersion KR process fluid flow
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Simulation of double cold cores of the 35°N section in the YellowSea with a wave-tide-circulation coupled model 被引量:7
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作者 夏长水 乔方利 +2 位作者 张勐宁 杨永增 袁业立 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第3期292-298,共7页
Based on the MASNUM wave-tide-circulation coupled numerical model, the temperature structure along 35°N in the Yellow Sea was simulated and compared with the observations. One of the notable features of the tempe... Based on the MASNUM wave-tide-circulation coupled numerical model, the temperature structure along 35°N in the Yellow Sea was simulated and compared with the observations. One of the notable features of the temperature structure along 35°N section is the double cold cores phenomena during spring and summer. The double cold cores refer to the two cold water centers located near 122°E and 125°E from the depth of 30m to bottom. The formation, maintenance and disappearance of the double cold cores are discussed. At least two reasons make the temperature in the center (near 123°E) of the section higher than that near the west and east shores in winter. One reason is that the water there is deeper than the west and east sides so its heat content is higher. The other is invasion of the warm water brought by the Yellow Sea Warm Current (YSWC) during winter.This temperature pattern of the lower layer (from 30m to bottom) is maintained through spring and summer when the upper layer (0 to 30m) is heated and strong thermocline is formed. Large zonal span of the 35°N section (about 600 km) makes the cold cores have more opportunity to survive. The double cold cores phenomena disappears in early autumn when the west cold core vanishes first with the dropping of the thermocline position. 展开更多
关键词 temperature The Yellow Sea wave-tide-circulation coupled model double cold cores
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Relationship between rock uniaxial compressive strength and digital core drilling parameters and its forecast method 被引量:6
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作者 Hongke Gao Qi Wang +3 位作者 Bei Jiang Peng Zhang Zhenhua Jiang Yue Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第4期605-613,共9页
The rock uniaxial compressive strength(UCS)is the basic parameter for support designs in underground engineering.In particular,the rock UCS should be obtained rapidly for underground engineering with complex geologica... The rock uniaxial compressive strength(UCS)is the basic parameter for support designs in underground engineering.In particular,the rock UCS should be obtained rapidly for underground engineering with complex geological conditions,such as soft rock,fracture areas,and high stress,to adjust the excavation and support plan and ensure construction safety.To solve the problem of obtaining real-time rock UCS at engineering sites,a rock UCS forecast idea is proposed using digital core drilling.The digital core drilling tests and uniaxial compression tests are performed based on the developed rock mass digital drilling system.The results indicate that the drilling parameters are highly responsive to the rock UCS.Based on the cutting and fracture characteristics of the rock digital core drilling,the mechanical analysis of rock cutting provides the digital core drilling strength,and a quantitative relationship model(CDP-UCS model)for the digital core drilling parameters and rock UCS is established.Thus,the digital core drilling-based rock UCS forecast method is proposed to provide a theoretical basis for continuous and quick testing of the surrounding rock UCS. 展开更多
关键词 Digital core drilling Mechanical analysis Rock UCS Quantitative relationship model Forecast method
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Influence of core box vents distribution on flow dynamics of core shooting process based on experiment and numerical simulation 被引量:4
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作者 Chang-jiang Ni Gao-chun Lu +4 位作者 Qing-dong Zhang Tao Jing Jun-jiao Wu Lin-long Yang Qin-fang Wu 《China Foundry》 SCIE 2016年第1期22-29,共8页
Core shooting process plays a decisive role in the quality of sand cores, and core box vents distribution is one of the most important factor determining the effectiveness of core shooting process. In this paper, the ... Core shooting process plays a decisive role in the quality of sand cores, and core box vents distribution is one of the most important factor determining the effectiveness of core shooting process. In this paper, the influence of core box vents distribution on the flow dynamics of core shooting process was investigated based on in situ experimental observations with transparent core box, high-speed camera and pressure measuring system. Attention was focused on the variation of both the flow behavior of sand and pressure curves due to different vents distribution. Taking both kinetic and frictional stress into account, a kinetic-frictional constitutive model was established to describe the internal momentum transfer in the solid phase. Two-fluid model(TFM) simulation was then performed and good agreement was achieved between the experimental and simulated results on both the flow behavior of sand and the pressure curves. It was found that vents distribution has direct effect on the pressure difference of different locations in the core box, which determines the buoyancy force exerting on the sand particles and significantly influences the filling process of core sand. 展开更多
关键词 vents distribution flow dynamics pressure variation core shooting process kinetic-frictional model two-fluid model
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Numerical modeling of metamorphic core complex formation:Implications for the destruction of the North China Craton 被引量:6
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作者 ZiQi Ma Gang Lu +1 位作者 JianFeng Yang Liang Zhao 《Earth and Planetary Physics》 EI CSCD 2022年第2期191-203,共13页
Widespread magmatism, metamorphic core complexes(MCCs), and significant lithospheric thinning occurred during the Mesozoic in the North China Craton(NCC). It has been suggested that the coeval exhumation of MCCs with ... Widespread magmatism, metamorphic core complexes(MCCs), and significant lithospheric thinning occurred during the Mesozoic in the North China Craton(NCC). It has been suggested that the coeval exhumation of MCCs with uniform northwest-southeast shear senses and magmatism probably resulted from a decratonization event during the retreat of the paleo-Pacific Plate. Here we used two-dimensional finite element thermomechanical numerical models to investigate critical parameters controlling the formation of MCCs under far-field extensional stress. We observed three end-member deformation modes: the MCC mode, the symmetric-dome mode, and the pure-shear mode. The MCC mode requires a Moho temperature of ≥700 ℃ and an extensional strain rate of ≥5 × 10^(-16)s^(-1), implying that the lithosphere had already thinned when the MCC was formed in the Mesozoic. Considering that the widespread MCCs have the same northwest-southeast extension direction in the NCC, we suggest that the MCCs are surface expressions of both large-scale extension and craton destruction and that rollback of the paleo-Pacific slab might be the common driving force. 展开更多
关键词 metamorphic core complex North China Craton numerical modeling EXTENSION
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Mathematical modeling for dynamic stability of sandwich beam with variable mechanical properties of core 被引量:3
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作者 M.GRYGOROWICZ E.MAGNUCKA-BLANDZI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第10期1361-1374,共14页
The paper is devoted to mathematical modelling of static and dynamic stability of a simply supported three-layered beam with a metal foam core. Mechanical properties of the core vary along the vertical direction. The ... The paper is devoted to mathematical modelling of static and dynamic stability of a simply supported three-layered beam with a metal foam core. Mechanical properties of the core vary along the vertical direction. The field of displacements is for- mulated using the classical broken line hypothesis and the proposed nonlinear hypothesis that generalizes the classical one. Using both hypotheses, the strains are determined as well as the stresses of each layer. The kinetic energy, the elastic strain energy, and the work of load are also determined. The system of equations of motion is derived using Hamilton's principle. Finally, the system of three equations is reduced to one equation of motion, in particular, the Mathieu equation. The Bubnov-Galerkin method is used to solve the system of equations of motion, and the Runge-Kutta method is used to solve the second-order differential equation. Numerical calculations are done for the chosen family of beams. The critical loads, unstable regions, angular frequencies of the beam, and the static and dynamic equilibrium paths are calculated analytically and verified numerically. The results of this study are presented in the forms of figures and tables. 展开更多
关键词 mathematical modelling dynamic stability metal foam core with variable mechanical property static and dynamic equilibrium path angular frequency
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Assessment of different genetic distances in constructing cotton core subset by genotypic values 被引量:7
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作者 Jian-cheng WANG Jin HU +1 位作者 Xin-xian HUANG Sheng-chun XU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第5期356-362,共7页
One hundred and sixty-eight genotypes of cotton from the same growing region were used as a germplasm group to study the validity of different genetic distances in constructing cotton core subset. Mixed linear model a... One hundred and sixty-eight genotypes of cotton from the same growing region were used as a germplasm group to study the validity of different genetic distances in constructing cotton core subset. Mixed linear model approach was employed to unbiasedly predict genotypic values of 20 traits for eliminating the environmental effect. Six commonly used genetic distances(Euclidean,standardized Euclidean,Mahalanobis,city block,cosine and correlation distances) combining four commonly used hierarchical cluster methods(single distance,complete distance,unweighted pair-group average and Ward's methods) were used in the least distance stepwise sampling(LDSS) method for constructing different core subsets. The analyses of variance(ANOVA) of different evaluating parameters showed that the validities of cosine and correlation distances were inferior to those of Euclidean,standardized Euclidean,Mahalanobis and city block distances. Standardized Euclidean distance was slightly more effective than Euclidean,Mahalanobis and city block distances. The principal analysis validated standardized Euclidean distance in the course of constructing practical core subsets. The covariance matrix of accessions might be ill-conditioned when Mahalanobis distance was used to calculate genetic distance at low sampling percentages,which led to bias in small-sized core subset construction. The standardized Euclidean distance is recommended in core subset construction with LDSS method. 展开更多
关键词 core subset Mixed linear model Least distance stepwise sampling (LDSS) method Standardized Euclidean distance Mahalanobis distance
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Geostatistics Studies and Geochemical Modeling Based on Core Data,Sheytoor Iron Deposit,Iran 被引量:6
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作者 Aref Shirazi Adel Shirazy +1 位作者 Shahab Saki Ardeshir Hezarkhani 《Journal of Geological Resource and Engineering》 2018年第3期124-133,共10页
In general,the purpose of the mineralization modeling is the advancement of a mineral exploration project and ultimately,the extractive design of a deposit,which is one of the most important stages in mining engineeri... In general,the purpose of the mineralization modeling is the advancement of a mineral exploration project and ultimately,the extractive design of a deposit,which is one of the most important stages in mining engineering.Mineralization modeling is divided into two general categories,superficial and deep modeling.In surface modeling,the aim is finding abnormal locations in terms of mineralization at the study area,which is commonly used in the early stages of exploration as one of the means for locating exploratory boreholes.After drilling in the study area with the aim of identifying mineralization and reserve estimation it is necessary to obtain deep mineralization position and its geometric features,using statistical and modeling methods.Using mathematical,statistical and modeling methods,we can predict the position of iron mineralization in places where drilling is not done and eventually reach a three-dimensional model of the mineral materials underground.As a case study,the deep information about the boreholes of the sheytoor mining area in Yazd province of Iran was investigated.Iron mineralization was modeled as 2D cumulative model and 3D block model,and the results were presented.Finally the geochemical threshold and the anomalous limit of iron element are calculated by concentration-volume(C-V)fractal method in this deposit.Geochemical threshold and the anomalous limit for Fe in this deposit are 24.7%and 34.3%respectively. 展开更多
关键词 ORE modeling C-V FRACTAL method IRON DEPOSIT core data sheytoor
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