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Structured Multi-Head Attention Stock Index Prediction Method Based Adaptive Public Opinion Sentiment Vector
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作者 Cheng Zhao Zhe Peng +2 位作者 Xuefeng Lan Yuefeng Cen Zuxin Wang 《Computers, Materials & Continua》 SCIE EI 2024年第1期1503-1523,共21页
The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment ... The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment risk.The quantification of investment sentiment indicators and the persistent analysis of their impact has been a complex and significant area of research.In this paper,a structured multi-head attention stock index prediction method based adaptive public opinion sentiment vector is proposed.The proposedmethod utilizes an innovative approach to transform numerous investor comments on social platforms over time into public opinion sentiment vectors expressing complex sentiments.It then analyzes the continuous impact of these vectors on the market through the use of aggregating techniques and public opinion data via a structured multi-head attention mechanism.The experimental results demonstrate that the public opinion sentiment vector can provide more comprehensive feedback on market sentiment than traditional sentiment polarity analysis.Furthermore,the multi-head attention mechanism is shown to improve prediction accuracy through attention convergence on each type of input information separately.Themean absolute percentage error(MAPE)of the proposedmethod is 0.463%,a reduction of 0.294% compared to the benchmark attention algorithm.Additionally,the market backtesting results indicate that the return was 24.560%,an improvement of 8.202% compared to the benchmark algorithm.These results suggest that themarket trading strategy based on thismethod has the potential to improve trading profits. 展开更多
关键词 Public opinion sentiment structured multi-head attention stock index prediction deep learning
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Prediction of atomization characteristics of pressure swirl nozzle with different structures
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作者 Jinfan Liu Xin Feng +4 位作者 Hu Liang Weipeng Zhang Yuanyuan Hui Haohan Xu Chao Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期171-184,共14页
The structure of the pressure swirl nozzle is an important factor affecting its spray performance.This work aims to study pressure swirl nozzles with different structures by experiment and simulation.In the experiment... The structure of the pressure swirl nozzle is an important factor affecting its spray performance.This work aims to study pressure swirl nozzles with different structures by experiment and simulation.In the experiment,10 nozzles with different structures are designed to comprehensively cover various geometric factors.In terms of simulation,steady-state simulation with less computational complexity is used to study the flow inside the nozzle.The results show that the diameter of the inlet and outlet,the direction of the inlet,the diameter of the swirl chamber,and the height of the swirl chamber all affect the atomization performance,and the diameter of the inlet and outlet has a greater impact.It is found that under the same flow rate and pressure,the geometric differences do have a significant impact on the atomization characteristics,such as spray angle and SMD(Sauter mean diameter).Specific nozzle structures can be customized according to the actual needs.Data analysis shows that the spray angle is related to the swirl number,and the SMD is related to turbulent kinetic energy.Through data fitting,the equations for predicting the spray angle and the SMD are obtained.The error range of the fitting equation for the prediction of spray angle and SMD is within 15% and 10% respectively.The prediction is expected to be used in engineering to estimate the spray performance at the beginning of a real project. 展开更多
关键词 Pressure swirl nozzle Nozzle structure Numerical simulation Spray angle prediction
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Structural and functional connectivity of the whole brain and subnetworks in individuals with mild traumatic brain injury:predictors of patient prognosis
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作者 Sihong Huang Jungong Han +4 位作者 Hairong Zheng Mengjun Li Chuxin Huang Xiaoyan Kui Jun Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1553-1558,共6页
Patients with mild traumatic brain injury have a diverse clinical presentation,and the underlying pathophysiology remains poorly understood.Magnetic resonance imaging is a non-invasive technique that has been widely u... Patients with mild traumatic brain injury have a diverse clinical presentation,and the underlying pathophysiology remains poorly understood.Magnetic resonance imaging is a non-invasive technique that has been widely utilized to investigate neuro biological markers after mild traumatic brain injury.This approach has emerged as a promising tool for investigating the pathogenesis of mild traumatic brain injury.G raph theory is a quantitative method of analyzing complex networks that has been widely used to study changes in brain structure and function.However,most previous mild traumatic brain injury studies using graph theory have focused on specific populations,with limited exploration of simultaneous abnormalities in structural and functional connectivity.Given that mild traumatic brain injury is the most common type of traumatic brain injury encounte red in clinical practice,further investigation of the patient characteristics and evolution of structural and functional connectivity is critical.In the present study,we explored whether abnormal structural and functional connectivity in the acute phase could serve as indicators of longitudinal changes in imaging data and cognitive function in patients with mild traumatic brain injury.In this longitudinal study,we enrolled 46 patients with mild traumatic brain injury who were assessed within 2 wee ks of injury,as well as 36 healthy controls.Resting-state functional magnetic resonance imaging and diffusion-weighted imaging data were acquired for graph theoretical network analysis.In the acute phase,patients with mild traumatic brain injury demonstrated reduced structural connectivity in the dorsal attention network.More than 3 months of followup data revealed signs of recovery in structural and functional connectivity,as well as cognitive function,in 22 out of the 46 patients.Furthermore,better cognitive function was associated with more efficient networks.Finally,our data indicated that small-worldness in the acute stage could serve as a predictor of longitudinal changes in connectivity in patients with mild traumatic brain injury.These findings highlight the importance of integrating structural and functional connectivity in unde rstanding the occurrence and evolution of mild traumatic brain injury.Additionally,exploratory analysis based on subnetworks could serve a predictive function in the prognosis of patients with mild traumatic brain injury. 展开更多
关键词 cognitive function CROSS-SECTION FOLLOW-UP functional connectivity graph theory longitudinal study mild traumatic brain injury prediction small-worldness structural connectivity subnetworks whole brain network
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Deformation,structure and potential hazard of a landslide based on InSAR in Banbar county,Xizang(Tibet)
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作者 Guan-hua Zhao Heng-xing Lan +4 位作者 Hui-yong Yin Lang-ping Li Alexander Strom Wei-feng Sun Chao-yang Tian 《China Geology》 CAS CSCD 2024年第2期203-221,共19页
The Tibetan Plateau is characterized by complex geological conditions and a relatively fragile ecological environment.In recent years,there has been continuous development and increased human activity in the Tibetan P... The Tibetan Plateau is characterized by complex geological conditions and a relatively fragile ecological environment.In recent years,there has been continuous development and increased human activity in the Tibetan Plateau region,leading to a rising risk of landslides.The landslide in Banbar County,Xizang(Tibet),have been perturbed by ongoing disturbances from human engineering activities,making it susceptible to instability and displaying distinct features.In this study,small baseline subset synthetic aperture radar interferometry(SBAS-InSAR)technology is used to obtain the Line of Sight(LOS)deformation velocity field in the study area,and then the slope-orientation deformation field of the landslide is obtained according to the spatial geometric relationship between the satellite’s LOS direction and the landslide.Subsequently,the landslide thickness is inverted by applying the mass conservation criterion.The results show that the movement area of the landslide is about 6.57×10^(4)m^(2),and the landslide volume is about 1.45×10^(6)m^(3).The maximum estimated thickness and average thickness of the landslide are 39 m and 22 m,respectively.The thickness estimation results align with the findings from on-site investigation,indicating the applicability of this method to large-scale earth slides.The deformation rate of the landslide exhibits a notable correlation with temperature variations,with rainfall playing a supportive role in the deformation process and displaying a certain lag.Human activities exert the most substantial influence on the spatial heterogeneity of landslide deformation,leading to the direct impact of several prominent deformation areas due to human interventions.Simultaneously,utilizing the long short-term memory(LSTM)model to predict landslide displacement,and the forecast results demonstrate the effectiveness of the LSTM model in predicting landslides that are in a continuous development and movement phase.The landslide is still active,and based on the spatial heterogeneity of landslide deformation,new recommendations have been proposed for the future management of the landslide in order to mitigate potential hazards associated with landslide instability. 展开更多
关键词 LANDSLIDE INSAR Human activity DEFORMATION structure LSTM model Engineering construction Thickness Neural network Machine learning prediction and prevention Tibetan Plateau Geological hazards survey engineering
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Uncertainty quantification of predicting stable structures for high-entropy alloys using Bayesian neural networks
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作者 Yonghui Zhou Bo Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期118-124,I0005,共8页
High entropy alloys(HEAs)have excellent application prospects in catalysis because of their rich components and configuration space.In this work,we develop a Bayesian neural network(BNN)based on energies calculated wi... High entropy alloys(HEAs)have excellent application prospects in catalysis because of their rich components and configuration space.In this work,we develop a Bayesian neural network(BNN)based on energies calculated with density functional theory to search the configuration space of the CoNiRhRu HEA system.The BNN model was developed by considering six independent features of Co-Ni,Co-Rh,CoRu,Ni-Rh,Ni-Ru,and Rh-Ru in different shells and energies of structures as the labels.The root mean squared error of the energy predicted by BNN is 1.37 me V/atom.Moreover,the influence of feature periodicity on the energy of HEA in theoretical calculations is discussed.We found that when the neural network is optimized to a certain extent,only using the accuracy indicator of root mean square error to evaluate model performance is no longer accurate in some scenarios.More importantly,we reveal the importance of uncertainty quantification for neural networks to predict new structures of HEAs with proper confidence based on BNN. 展开更多
关键词 Uncertainty quantification High-entropy alloys Bayesian neural networks Energy prediction structure screening
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The CALYPSO methodology for structure prediction 被引量:2
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作者 童群超 吕健 +1 位作者 高朋越 王彦超 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期22-29,共8页
Structure prediction methods have been widely used as a state-of-the-art tool for structure searches and materials discovery, leading to many theory-driven breakthroughs on discoveries of new materials. These methods ... Structure prediction methods have been widely used as a state-of-the-art tool for structure searches and materials discovery, leading to many theory-driven breakthroughs on discoveries of new materials. These methods generally involve the exploration of the potential energy surfaces of materials through various structure sampling techniques and optimization algorithms in conjunction with quantum mechanical calculations. By taking advantage of the general feature of materials potential energy surface and swarm-intelligence-based global optimization algorithms, we have developed the CALYPSO method for structure prediction, which has been widely used in fields as diverse as computational physics, chemistry, and materials science. In this review, we provide the basic theory of the CALYPSO method, placing particular emphasis on the principles of its various structure dealing methods. We also survey the current challenges faced by structure prediction methods and include an outlook on the future developments of CALYPSO in the conclusions. 展开更多
关键词 structure prediction CALYPSO method CRYSTAL structure POTENTIAL ENERGY surface
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Mem Brain: An Easy-to-Use Online Webserver for Transmembrane Protein Structure Prediction 被引量:3
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作者 Xi Yin Jing Yang +2 位作者 Feng Xiao Yang Yang Hong-Bin Shen 《Nano-Micro Letters》 SCIE EI CAS 2018年第1期12-19,共8页
Membrane proteins are an important kind of proteins embedded in the membranes of cells and play crucial roles in living organisms, such as ion channels,transporters, receptors. Because it is difficult to determinate t... Membrane proteins are an important kind of proteins embedded in the membranes of cells and play crucial roles in living organisms, such as ion channels,transporters, receptors. Because it is difficult to determinate the membrane protein's structure by wet-lab experiments,accurate and fast amino acid sequence-based computational methods are highly desired. In this paper, we report an online prediction tool called Mem Brain, whose input is the amino acid sequence. Mem Brain consists of specialized modules for predicting transmembrane helices, residue–residue contacts and relative accessible surface area of a-helical membrane proteins. Mem Brain achieves aprediction accuracy of 97.9% of ATMH, 87.1% of AP,3.2 ± 3.0 of N-score, 3.1 ± 2.8 of C-score. Mem BrainContact obtains 62%/64.1% prediction accuracy on training and independent dataset on top L/5 contact prediction,respectively. And Mem Brain-Rasa achieves Pearson correlation coefficient of 0.733 and its mean absolute error of13.593. These prediction results provide valuable hints for revealing the structure and function of membrane proteins.Mem Brain web server is free for academic use and available at www.csbio.sjtu.edu.cn/bioinf/Mem Brain/. 展开更多
关键词 Transmembrane a-helices structure prediction Machine learning Contact map prediction Relative accessible surface area
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Variable structure control with sliding mode prediction for discrete-time nonlinear systems 被引量:4
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作者 Lingfei XIAO Hongye SU Xiaoyu ZHANG Jian CHU 《控制理论与应用(英文版)》 EI 2006年第2期140-146,共7页
A new variable structure control algorithm based on sliding mode prediction for a class of discrete-time nonlinear systems is presented. By employing a special model to predict future sliding mode value, and combining... A new variable structure control algorithm based on sliding mode prediction for a class of discrete-time nonlinear systems is presented. By employing a special model to predict future sliding mode value, and combining feedback correction and receding horizon optimization methods which are extensively applied on predictive control strategy, a discrete-time variable structure control law is constructed. The closed-loop systems are proved to have robustness to uncertainties with unspecified boundaries. Numerical simulation and pendulum experiment results illustrate that the closed-loop systems possess desired performance, such as strong robustness, fast convergence and chattering elimination. 展开更多
关键词 Variable structure control Sliding mode prediction Discrete-time nonlinear system Pendulum experiment
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Cluster structure prediction via CALYPSO method 被引量:1
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作者 田永红 孙伟国 +2 位作者 陈伯乐 金圆圆 卢成 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期1-9,共9页
Cluster science as a bridge linking atomic molecular physics and condensed matter inspired the nanomaterials development in the past decades, ranging from the single-atom catalysis to ligand-protected noble metal clus... Cluster science as a bridge linking atomic molecular physics and condensed matter inspired the nanomaterials development in the past decades, ranging from the single-atom catalysis to ligand-protected noble metal clusters. The corresponding studies not only have been restricted to the search for the geometrical structures of clusters, but also have promoted the development of cluster-assembled materials as the building blocks. The CALYPSO cluster prediction method combined with other computational techniques have significantly stimulated the development of the cluster-based nanomaterials. In this review, we will summarize some good cases of cluster structure by CALYPSO method, which have also been successfully identified by the photoelectron spectra experiments. Beginning with the alkali-metal clusters, which serve as benchmarks, a series of studies are performed on the size-dependent elemental clusters which possess relatively high stability and interesting chemical physical properties. Special attentions are paid to the boron-based clusters because of their promising applications. The NbSi12 and BeB16 clusters, for example, are two classic representatives of the silicon-and boron-based clusters, which can be viewed as building blocks of nanotubes and borophene. This review offers a detailed description of the structural evolutions and electronic properties of medium-sized pure and doped clusters, which will advance fundamental knowledge of cluster-based nanomaterials and provide valuable information for further theoretical and experimental studies. 展开更多
关键词 CALYPSO METHOD CLUSTER structure prediction BORON CLUSTER SILICON CLUSTER
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RNA structure prediction:Progress and perspective 被引量:1
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作者 时亚洲 吴园燕 +1 位作者 王凤华 谭志杰 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期88-97,共10页
Many recent exciting discoveries have revealed the versatility of RNAs and their importance in a variety of cellular functions which are strongly coupled to RNA structures. To understand the functions of RNAs, some st... Many recent exciting discoveries have revealed the versatility of RNAs and their importance in a variety of cellular functions which are strongly coupled to RNA structures. To understand the functions of RNAs, some structure prediction models have been developed in recent years. In this review, the progress in computational models for RNA structure prediction is introduced and the distinguishing features of many outstanding algorithms are discussed, emphasizing three- dimensional (3D) structure prediction. A promising coarse-grained model for predicting RNA 3D structure, stability and salt effect is also introduced briefly. Finally, we discuss the major challenges in the RNA 3D structure modeling. 展开更多
关键词 RNA structure prediction secondary structure three-dimensional (3D) structure coarse-grainedmodel
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Prediction of Compressive and Shear Moduli of X-cor Sandwich Structures for Aeronautic Engineering 被引量:1
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作者 张向阳 李勇 +3 位作者 李俊斐 范琳 谭永刚 肖军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第6期646-653,共8页
The so-called″X-cor sandwich structure″is a highly promising novel material as an alternative to honeycomb used in aircraft.Although much work has been conducted on the performance of the X-cor sandwich structure,th... The so-called″X-cor sandwich structure″is a highly promising novel material as an alternative to honeycomb used in aircraft.Although much work has been conducted on the performance of the X-cor sandwich structure,the gap is still hardly bridged between experimental results and theoretical analyses.Therefore,a method has been innovated to establish semi-empirical formula for the prediction of compressive and shear moduli of X-cor sandwich structure composites,by combining theoretical analyses and experimental data.In addition,aprediction software was first developed based on the proposed method,of which the accuracy was verified through confirmatory experiments.This software can offer a direct reference or guide for engineers in structural designing. 展开更多
关键词 X-cor sandwich structure moduli prediction COMPRESSIVE SHEAR
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Typhoon Track,Intensity,and Structure:From Theory to Prediction 被引量:1
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作者 Zhe-Min TAN Lili LEI +2 位作者 Yuqing WANG Yinglong XU Yi ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第11期1789-1799,共11页
To improve understanding of essential aspects that influence forecasting of tropical cyclones(TCs),the National Key Research and Development Program,Ministry of Science and Technology of the People's Republic of C... To improve understanding of essential aspects that influence forecasting of tropical cyclones(TCs),the National Key Research and Development Program,Ministry of Science and Technology of the People's Republic of China conducted a five-year project titled“Key Dynamic and Thermodynamic Processes and Prediction for the Evolution of Typhoon Intensity and Structure”(KPPT).Through this project,new understandings of TC intensification,including outer rainbanddriven secondary eyewall formation and the roles of boundary layer dynamics and vertical wind shear,and improvements to TC data assimilation with integrated algorithms and adaptive localizations are achieved.To promote a breakthrough in TC intensity and structure forecasting,a new paradigm for TC evolution dynamics(i.e.,the correlations,interactions,and error propagation among the triangle of TC track,intensity,and structure)is proposed;and an era of dynamic-constrained,big-data driven,and strongly coupled data assimilation at the subkilometer scale and seamless prediction is expected. 展开更多
关键词 TYPHOONS TRACK INTENSITY structure theories predictions
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Neural Network Based on GA-BP Algorithm and its Application in the Protein Secondary Structure Prediction 被引量:8
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作者 YANG Yang LI Kai-yang 《Chinese Journal of Biomedical Engineering(English Edition)》 2006年第1期1-9,共9页
The advantages and disadvantages of genetic algorithm and BP algorithm are introduced. A neural network based on GA-BP algorithm is proposed and applied in the prediction of protein secondary structure, which combines... The advantages and disadvantages of genetic algorithm and BP algorithm are introduced. A neural network based on GA-BP algorithm is proposed and applied in the prediction of protein secondary structure, which combines the advantages of BP and GA. The prediction and training on the neural network are made respectively based on 4 structure classifications of protein so as to get higher rate of predication---the highest prediction rate 75.65%,the average prediction rate 65.04%. 展开更多
关键词 BP ALGORITHM GENETIC algorithm NEURAL network structure classification Protein SECONDARY structure prediction
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Computational prediction of RNA tertiary structures using machine learning methods 被引量:1
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作者 黄斌 杜渊洋 +3 位作者 张帅 李文飞 王骏 张建 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期17-23,共7页
RNAs play crucial and versatile roles in biological processes. Computational prediction approaches can help to understand RNA structures and their stabilizing factors, thus providing information on their functions, an... RNAs play crucial and versatile roles in biological processes. Computational prediction approaches can help to understand RNA structures and their stabilizing factors, thus providing information on their functions, and facilitating the design of new RNAs. Machine learning (ML) techniques have made tremendous progress in many fields in the past few years. Although their usage in protein-related fields has a long history, the use of ML methods in predicting RNA tertiary structures is new and rare. Here, we review the recent advances of using ML methods on RNA structure predictions and discuss the advantages and limitation, the difficulties and potentials of these approaches when applied in the field. 展开更多
关键词 RNA structure prediction RNA scoring function knowledge-based potentials machine learning convolutional neural networks
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Dynamic globularization prediction during cogging process of large size TC11 titanium alloy billet with lamellar structure 被引量:6
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作者 Hong-wu SONG Shi-hong ZHANG Ming CHENG 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第1期40-46,共7页
The flow behavior and dynamic globularization of TC11 titanium alloy during subtransus deformation are investigated through hot compression tests. A constitutive model is established based on physical-based hardening ... The flow behavior and dynamic globularization of TC11 titanium alloy during subtransus deformation are investigated through hot compression tests. A constitutive model is established based on physical-based hardening model and phenomenological softening model. And based on the recrystallization mechanisms of globularization, the Avrami type kinetics model is established for prediction of globularization fraction and globularized grain size under large strain subtransus deformation of TC11 alloy. As the preliminary application of the previous results, the cogging process of large size TC11 alloy billet is simulated. Based on subroutine development of the DEFORM software, the coupled simulation of one fire cogging process is developed. It shows that the predicted results are in good agreement with the experimental results in forging load and microstructure characteristic, which validates the reliability of the developed FEM subroutine models. 展开更多
关键词 TC11钛合金 大尺寸 球化 预测 开坯 层结构 带坯 TC11合金
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Analysis of the ore-controlling structure of the Shihu gold deposit, Hebei Province and deep-seated ore-prospecting prediction 被引量:6
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作者 NIU Shuyin WANG Baode +9 位作者 SUN Aiqun CHEN Chao WANG Zili MA Baojun WANG Wenxue JIANG Xiaoping ZHAO Yongli GAO Yincang LIU Huabin QIU Jianping 《Chinese Journal Of Geochemistry》 EI CAS 2009年第4期386-396,共11页
Under the guidance of the theory of mantle-branch structure-associated metallogenesis and on the basis of the geological characteristics, analysis of the ore-forming and ore-controlling structures, the geochemical cha... Under the guidance of the theory of mantle-branch structure-associated metallogenesis and on the basis of the geological characteristics, analysis of the ore-forming and ore-controlling structures, the geochemical characteristics of metallogenesis, the source of ore-forming materials, changes in the physical and chemical conditions of metallogenesis, changes in the vertical width of ore veins, and changes in gold grade of the Shihu gold deposit, the mechanism of its metallogenesis was discussed and the rules of vertical variation of ore veins were summarized in this study. It is pointed out that the orebodies under exploitation at present time should be in the middle and upper portions of gold veins in the Shihu gold mining district. Particularly on the basis of the characteristics of mantle-branch structure-associated metallogenesis, it is indicated that metallogenesis is controlled mainly by such ore-forming conditions as temperature and pressure. Deep-seated ore-forming fluids are characterized mainly by injection and precipitation. So the vein bodies in the adjacent metallogenic structures are of obvious comparability, and there would be great prospects for ore search both at depth and in the periphery of the Shihu gold deposit. Therefore, ore prospecting should be strengthened both at depth and in the peripheries. 展开更多
关键词 分支结构 找矿预测 金矿脉 控矿 河北省 成矿理论 地球化学特征 成矿物质来源
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Protein Secondary Structure Prediction with Dynamic Self-Adaptation Combination Strategy Based on Entropy 被引量:1
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作者 Yuehan Du Ruoyu Zhang +4 位作者 Xu Zhang Antai Ouyang Xiaodong Zhang Jinyong Cheng Wenpeng Lu 《Journal of Quantum Computing》 2019年第1期21-28,共8页
The algorithm based on combination learning usually is superior to a singleclassification algorithm on the task of protein secondary structure prediction. However,the assignment of the weight of the base classifier us... The algorithm based on combination learning usually is superior to a singleclassification algorithm on the task of protein secondary structure prediction. However,the assignment of the weight of the base classifier usually lacks decision-makingevidence. In this paper, we propose a protein secondary structure prediction method withdynamic self-adaptation combination strategy based on entropy, where the weights areassigned according to the entropy of posterior probabilities outputted by base classifiers.The higher entropy value means a lower weight for the base classifier. The final structureprediction is decided by the weighted combination of posterior probabilities. Extensiveexperiments on CB513 dataset demonstrates that the proposed method outperforms theexisting methods, which can effectively improve the prediction performance. 展开更多
关键词 Multi-classifier combination ENTROPY protein secondary structure prediction dynamic self-adaptation
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A study on the numerical prediction method for the vertical thermal structure in the Bohai Sea and the Huanghai Sea-I.One-dimensional numerical prediction model 被引量:1
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作者 Wang Zongshan, Xu Bochang, Zou Emei, Yang Keqi Li Fanhua First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第1期25-34,共10页
In this paper, on the basis of the heat conduction equation without consideration of the advection and turbulence effects, one-dimensional model for describing surface sea temperature ( T1), bottom sea temperature ( T... In this paper, on the basis of the heat conduction equation without consideration of the advection and turbulence effects, one-dimensional model for describing surface sea temperature ( T1), bottom sea temperature ( Tt ) and the thickness of the upper homogeneous layer ( h ) is developed in terms of the dimensionless temperature θT and depth η and self-simulation function θT - f(η) of vertical temperature profile by means of historical temperature data.The results of trial prediction with our one-dimensional model on T, Th, h , the thickness and gradient of thermocline are satisfactory to some extent. 展开更多
关键词 A study on the numerical prediction method for the vertical thermal structure in the Bohai Sea and the Huanghai Sea-I.One-dimensional numerical prediction model
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The Analysis of Seismic Data Structure and Oil and Gas Prediction 被引量:14
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作者 WangShangxu LinChangrong 《Applied Geophysics》 SCIE CSCD 2004年第2期75-82,共8页
In this paper, a new concept called numerical structure of seismic data is introduced and the difference between numerical structure and numerical value of seismic data is explained. Our study shows that the numerical... In this paper, a new concept called numerical structure of seismic data is introduced and the difference between numerical structure and numerical value of seismic data is explained. Our study shows that the numerical seismic structure is closely related to oil and gas-bearing reservoir,so it is very useful for a geologist or a geophysicist to precisely interpret the oil-bearing layers from the seismic data. This technology can be applied to any exploration or production stage. The new method has been tested on a series of exploratory or development wells and proved to be reliable in China. Hydrocarbon-detection with this new method for 39 exploration wells on 25 structures indicates a success ratio of over 80 percent. The new method of hydrocarbon prediction can be applied for: (1) depositional environment of reservoirs with marine facies, delta, or non-marine facies (including fluvial facies, lacustrine facies); (2) sedimentary rocks of reservoirs that are non-marine clastic rocks and carbonate rock; and (3) burial depths range from 300 m to 7000 m, and the minimum thickness of these reservoirs is over 8 m (main frequency is about 50 Hz). 展开更多
关键词 碳氢化合物预测 承压地层 地震面 数据结构
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Geoscience material structures prediction via CALYPSO methodology
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作者 Andreas Hermann 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期38-49,共12页
Many properties of planets such as their interior structure and thermal evolution depend on the high-pressure properties of their constituent materials. This paper reviews how crystal structure prediction methodology ... Many properties of planets such as their interior structure and thermal evolution depend on the high-pressure properties of their constituent materials. This paper reviews how crystal structure prediction methodology can help shed light on the transformations materials undergo at the extreme conditions inside planets. The discussion focuses on three areas:(i) the propensity of iron to form compounds with volatile elements at planetary core conditions(important to understand the chemical makeup of Earth's inner core),(ii) the chemistry of mixtures of planetary ices(relevant for the mantle regions of giant icy planets), and(iii) examples of mantle minerals. In all cases the abilities and current limitations of crystal structure prediction are discussed across a range of example studies. 展开更多
关键词 crystal structure prediction core materials PLANETARY ICES HYDROUS MINERALS
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