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Absorption compensation via structure tensor regularization multichannel inversion
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作者 Liang Bing Zhao Dong-feng +4 位作者 Xia Lian-jun Tang Guo-song Luo Zhen Guan Wen-hua Wang Xue-jing 《Applied Geophysics》 2025年第3期635-646,892,893,共14页
Absorption compensation is a process involving the exponential amplification of reflection amplitudes.This process amplifies the seismic signal and noise,thereby substantially reducing the signal-tonoise ratio of seis... Absorption compensation is a process involving the exponential amplification of reflection amplitudes.This process amplifies the seismic signal and noise,thereby substantially reducing the signal-tonoise ratio of seismic data.Therefore,this paper proposes a multichannel inversion absorption compensation method based on structure tensor regularization.First,the structure tensor is utilized to extract the spatial inclination of seismic signals,and the spatial prediction filter is designed along the inclination direction.The spatial prediction filter is then introduced into the regularization condition of multichannel inversion absorption compensation,and the absorption compensation is realized under the framework of multichannel inversion theory.The spatial predictability of seismic signals is also introduced into the objective function of absorption compensation inversion.Thus,the inversion system can effectively suppress the noise amplification effect during absorption compensation and improve the recovery accuracy of high-frequency signals.Synthetic and field data tests are conducted to demonstrate the accuracy and effectiveness of the proposed method. 展开更多
关键词 Absorption compensation structure tensor RESOLUTION Signal-to-noise ratio regularIZATION
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Mechanical response identification of local interconnections in board- level packaging structures under projectile penetration using Bayesian regularization
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作者 Xu Long Yuntao Hu Irfan Ali 《Defence Technology(防务技术)》 2025年第7期79-95,共17页
Modern warfare demands weapons capable of penetrating substantial structures,which presents sig-nificant challenges to the reliability of the electronic devices that are crucial to the weapon's perfor-mance.Due to... Modern warfare demands weapons capable of penetrating substantial structures,which presents sig-nificant challenges to the reliability of the electronic devices that are crucial to the weapon's perfor-mance.Due to miniaturization of electronic components,it is challenging to directly measure or numerically predict the mechanical response of small-sized critical interconnections in board-level packaging structures to ensure the mechanical reliability of electronic devices in projectiles under harsh working conditions.To address this issue,an indirect measurement method using the Bayesian regularization-based load identification was proposed in this study based on finite element(FE)pre-dictions to estimate the load applied on critical interconnections of board-level packaging structures during the process of projectile penetration.For predicting the high-strain-rate penetration process,an FE model was established with elasto-plastic constitutive models of the representative packaging ma-terials(that is,solder material and epoxy molding compound)in which material constitutive parameters were calibrated against the experimental results by using the split-Hopkinson pressure bar.As the impact-induced dynamic bending of the printed circuit board resulted in an alternating tensile-compressive loading on the solder joints during penetration,the corner solder joints in the edge re-gions experience the highest S11 and strain,making them more prone to failure.Based on FE predictions at different structural scales,an improved Bayesian method based on augmented Tikhonov regulariza-tion was theoretically proposed to address the issues of ill-posed matrix inversion and noise sensitivity in the load identification at the critical solder joints.By incorporating a wavelet thresholding technique,the method resolves the problem of poor load identification accuracy at high noise levels.The proposed method achieves satisfactorily small relative errors and high correlation coefficients in identifying the mechanical response of local interconnections in board-level packaging structures,while significantly balancing the smoothness of response curves with the accuracy of peak identification.At medium and low noise levels,the relative error is less than 6%,while it is less than 10%at high noise levels.The proposed method provides an effective indirect approach for the boundary conditions of localized solder joints during the projectile penetration process,and its philosophy can be readily extended to other scenarios of multiscale analysis for highly nonlinear materials and structures under extreme loading conditions. 展开更多
关键词 Board-level packaging structure High strain-rate constitutive model Load identification Bayesian regularization Wavelet thresholding method
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INDUCTION—POLYMERIZATION OF PREPARING POLYMERS OF REGULAR STRUCTURE
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作者 Hsiao Lin CHANG, You An Map, Yi Men CHENG Department of Materials Science and Applied Chemistry, National University of Defence Technology, Changsha, 410073 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期821-822,共2页
Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points... Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points and polymerized to polymer of regular structure. Regularity of structure of the polyacrylamide prepared by this means has been verified with electron diffractograms, DSC curve and IR spectrum of the polymer. 展开更多
关键词 TEM INDUCTION POLYMERIZATION OF PREPARING POLYMERS OF regular structure
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Modeling of 3D-structure for regular fragments of low similarity unknown structure proteins
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作者 彭志红 Chen Jie Lin Xiwen Sang Yanchao 《High Technology Letters》 EI CAS 2007年第4期431-435,共5页
Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular ... Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular fragments (α-Helices, β-Strands) of such proteins by the protein secondary structure prediction software, the Basic Local Alignment Search Tool (BLAST) and the side chain construction software SCWRL3. First, the protein secondary structure prediction software is adopted to extract secondary structure fragments from the unknown structure proteins. Then, regular fragments are regulated by BLAST based on comparative modeling, providing main chain configurations. Finally, SCWRL3 is applied to assemble side chains for regular fragments, so that 3D-structure of regular fragments of low similarity unknown structure protein is obtained. Regular fragments of several neurotoxins are used for test. Simulation results show that the prediction errors are less than 0.06nm for regular fragments less than 10 amino acids, implying the simpleness and effectiveness of the proposed method. 展开更多
关键词 low similarity unknown structure regular segment 3D-structure modeling main chain confonnation side chain assembly
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Ore-controlling Regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District
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作者 Gong Hongsheng Han Runsheng +2 位作者 Li Ziteng Ren Tao Wang Jiasheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期202-203,共2页
1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is ... 1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is strictly controlled by fault structures.It has developed to one of the famous production bases of lead&zinc and germanium in China. 展开更多
关键词 PB Ore-controlling regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District Zn
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MPS-FEM Coupled Method for Study of Wave-Structure Interaction 被引量:4
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作者 Guanyu Zhang Xiang Chen Decheng Wan 《Journal of Marine Science and Application》 CSCD 2019年第4期387-399,共13页
Nowadays,an increasing number of ships and marine structures are manufactured and inevitably operated in rough sea.As a result,some phenomena related to the violent fluid-elastic structure interactions(e.g.,hydrodynam... Nowadays,an increasing number of ships and marine structures are manufactured and inevitably operated in rough sea.As a result,some phenomena related to the violent fluid-elastic structure interactions(e.g.,hydrodynamic slamming on marine vessels,tsunami impact on onshore structures,and sloshing in liquid containers)have aroused huge challenges to ocean engineering fields.In this paper,the moving particle semi-implicit(MPS)method and finite element method(FEM)coupled method is proposed for use in numerical investigations of the interaction between a regular wave and a horizontal suspended structure.The fluid domain calculated by the MPS method is dispersed into fluid particles,and the structure domain solved by the FEM method is dispersed into beam elements.The generation of the 2D regular wave is firstly conducted,and convergence verification is performed to determine appropriate particle spacing for the simulation.Next,the regular wave interacting with a rigid structure is initially performed and verified through the comparison with the laboratory experiments.By verification,the MPS-FEM coupled method can be applied to fluid-structure interaction(FSI)problems with waves.On this basis,taking the flexibility of structure into consideration,the elastic dynamic response of the structure subjected to the wave slamming is investigated,including the evolutions of the free surface,the variation of the wave impact pressures,the velocity distribution,and the structural deformation response.By comparison with the rigid case,the effects of the structural flexibility on wave-elastic structure interaction can be obtained. 展开更多
关键词 MPS-FEM coupled method Fluid-structure interaction(FSI) regular wave Wave impact pressure structure deformation response
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Inverse Load Identification in Stiffened Plate Structure Based on in situ Strain Measurement 被引量:1
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作者 Yihua Wang Zhenhuan Zhou +2 位作者 Hao Xu Shuai Li Zhanjun Wu 《Structural Durability & Health Monitoring》 EI 2021年第2期85-101,共17页
For practical engineering structures,it is usually difficult to measure external load distribution in a direct manner,which makes inverse load identification important.Specifically,load identification is a typical inv... For practical engineering structures,it is usually difficult to measure external load distribution in a direct manner,which makes inverse load identification important.Specifically,load identification is a typical inverse problem,for which the models(e.g.,response matrix)are often ill-posed,resulting in degraded accuracy and impaired noise immunity of load identification.This study aims at identifying external loads in a stiffened plate structure,through comparing the effectiveness of different methods for parameter selection in regulation problems,including the Generalized Cross Validation(GCV)method,the Ordinary Cross Validation method and the truncated singular value decomposition method.With demonstrated high accuracy,the GCV method is used to identify concentrated loads in three different directions(e.g.,vertical,lateral and longitudinal)exerted on a stiffened plate.The results show that the GCV method is able to effectively identify multi-source static loads,with relative errors less than 5%.Moreover,under the situation of swept frequency excitation,when the excitation frequency is near the natural frequency of the structure,the GCV method can achieve much higher accuracy compared with direct inversion.At other excitation frequencies,the average recognition error of the GCV method load identification less than 10%. 展开更多
关键词 structural health monitoring load identification Tikhonov regularization generalized cross validation stiffened plate structure
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Analysis on geological structures influencing gas occurrence at Qidong coalmine 被引量:1
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作者 WU Shi-yong HU Bao-lin YAO Duo-xi ZHANG De-sheng 《Journal of Coal Science & Engineering(China)》 2010年第3期292-295,共4页
The occurrence state of methane is mostly controlled by coalfield geologicalstructures.The coal-bearing strata at Qidong coalmine experienced many tectonic cyclessince their formation.The gas content made by the compl... The occurrence state of methane is mostly controlled by coalfield geologicalstructures.The coal-bearing strata at Qidong coalmine experienced many tectonic cyclessince their formation.The gas content made by the complicated structural geologic systemat the coalfield is very different, which is obviously higher on the north side of the Weimiaofracture belt than that on the south side and near itself.This thesis discussed the gas occurrenceregularity based on the geometric characteristics of the geological structure andits regional tectonic evolution.This study can provide a foundation for coalfield exploitationand deal with coal and gas outburst. 展开更多
关键词 geological structure evolutional regularity gas occurrence Qidong coalmine
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RGBD Salient Object Detection by Structured Low-Rank Matrix Recovery and Laplacian Constraint 被引量:1
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作者 Chang Tang Chunping Hou 《Transactions of Tianjin University》 EI CAS 2017年第2期176-183,共8页
A structured low-rank matrix recovery model for RGBD salient object detection is proposed. Firstly, the problem is described by a low-rank matrix recovery, and the hierarchical structure of RGB image is added to the s... A structured low-rank matrix recovery model for RGBD salient object detection is proposed. Firstly, the problem is described by a low-rank matrix recovery, and the hierarchical structure of RGB image is added to the sparsity term. Secondly, the depth information is fused into the model by a Laplacian regularization term to ensure that the image regions which share similar depth value will be allocated to similar saliency value. Thirdly, a variation of alternating direction method is proposed to solve the proposed model. Finally, both quantitative and qualitative experimental results on NLPR1000 and NJU400 show the advantage of the proposed RGBD salient object detection model. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Laplace transforms Object recognition RECOVERY
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The Principle of Square Hole Machining and It's Tooling Structure Design
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作者 Jinxia NIU 《International Journal of Technology Management》 2015年第2期7-8,共2页
In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and pro... In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel. 展开更多
关键词 Abstract: In order to meet the rapid needs of processing square hole in mechanical equipment the paper expounds the square hole processing method: planetary wheel method and analyze the principle of tooling structure and process with computer graphics parameters design. The results that as long as the appropriate parameters using the above method not only can punch the square hole can also be processed triangle the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel. Keywords: Square hole processing Planet wheel Lelo triangle Square hole drilling
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Data-Path Placement Based on Regularity Extraction and Implementation
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作者 杨长旗 洪先龙 +2 位作者 蔡懿慈 经彤 吴为民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第8期925-936,共12页
An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal ... An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal flow of circuit.Then,it converts the bit slice structure to parallel constraints to enable Q place algorithm.The design flow and the main algorithms are introduced.Finally,the satisfied experimental result of the tool compared with the Cadence placement tool SE is discussed. 展开更多
关键词 Data Path regularity extraction bit slice structure Q place
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Analysis on Structural Control of Coal Distribution in the Northern Qaidam Basin,NW China 被引量:3
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作者 LIU Tianji WANG Tong ZHAN Wenfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期690-696,共7页
The distribution of the Jurassic coal measures in the northern Qaidam Basin is obviously controlled by the regional structures. Based on the existing data of coalfield exploration and combined with the analysis of coa... The distribution of the Jurassic coal measures in the northern Qaidam Basin is obviously controlled by the regional structures. Based on the existing data of coalfield exploration and combined with the analysis of coalfield basement structures, features of the main faults, and the distribution of coal measures, this paper brings forward a scheme of coalfield tectonic divisional units and the definition of the coal-controlling structural styles in the northern Qaidam Basin. The structure control of the distribution of coal measures is further discussed. Several stages of regional tectonic activities since the Indosinian has led to the distribution of coal measures into the characteristics of zonation from the north to south and block from east to west. The results indicate that the structural deformations are the most intense in the front of the three uplifted belts, which are characterized by the combination of thrusts. The coal measures are uplifted to the shallow formations, and are easy to be exploited, but the scale of mines is small because of serious damages by the coal distribution. On the contrary, the stress and strain are weak in the three depressions, with the coal-controlling structural styles being mainly the thrust-fold and thrust-monocline combinations. The distribution of coals in the depressions is relatively stable. The shallower part of the depression will become the key areas for exploration and development of coal resources in the northern Qaidam Basin. 展开更多
关键词 northern Qaidam Basin tectonic units coal-controlling structural styles distribution regularity of coal measures
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Occurrence characteristics and enrichment regularity of indium in pyrite: A case study of Dachang tin ore-field 被引量:2
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作者 Yong-sheng CHENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第8期2197-2208,共12页
To reveal the occurrence state and enrichment regularity of the dispersed element indium in pyrite, the petrology,mineralogy, geochemistry, and mineral physics were researched detailedly. The results suggest that the ... To reveal the occurrence state and enrichment regularity of the dispersed element indium in pyrite, the petrology,mineralogy, geochemistry, and mineral physics were researched detailedly. The results suggest that the structure of pyrite is mainlycomposed of massive structure, disseminated structure, vein structure, reticular structure, comb structure and so on. Generally, thepyrite coexists with sphalerite, marmatite, pyrrhotite, chalcopyrite, galena, and arsenopyrite. And the texture of pyrite primarilyconsists of the metasomatic texture, solid solution texture, idiomorphic?hypidiomorphic granular texture, and disseminated texture.The content of indium in pyrite ranges from 0.491×10?6 to 65.1×10?6 with an average value of 14.38×10?6. Yet, the indium content inthe Gaofeng deposit is higher than that in the Dafulou and Tongkeng deposit, showing a particularly significant supernormalenrichment. Besides, the cadmium content in pyrite is also higher than other dispersed elements, and similarly the abnormalenrichment of cadmium in the Gaofeng deposit is also very significant. An obvious positive correlation exists between In and Cd, orTl, but a negative correlation between In and Re. It is difficult to find out a positive or negative correlation between In and Ga. Theelement zinc is of great importance to the enrichment of indium, which can possibly facilitate to the migration and crystallization of dispersed element indium. 展开更多
关键词 dispersed element indium PYRITE lattice structure enrichment regularity cassiterite-sulfide deposit Dachang ore-field
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Some Properties of a Recursive Procedure for High Dimensional Parameter Estimation in Linear Model with Regularization
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作者 Hong Son Hoang Remy Baraille 《Open Journal of Statistics》 2014年第11期921-932,共12页
Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed t... Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed to overcome the difficulties with high dimension of the observation vector in computation of a statistical regularized estimator. As to deal with high dimension of the vector of unknown parameters, the regularization is introduced by specifying a priori non-negative covariance structure for the vector of estimated parameters. Numerical example with Monte-Carlo simulation for a low-dimensional system as well as the state/parameter estimation in a very high dimensional oceanic model is presented to demonstrate the efficiency of the proposed approach. 展开更多
关键词 Linear Model regularIZATION RECURSIVE Algorithm Non-Negative COVARIANCE structure EIGENVALUE Decomposition
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Structural Connectivity Enhanced Anisotropic 3D Network for Brain Midline Delineation
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作者 Yufan Liu Kongming Liang +6 位作者 Yinuo Jing Shen Wang Zhanyu Ma Yiming Li Yizhou Yu Yizhou Wang Jun Guo 《Journal of Beijing Institute of Technology》 EI CAS 2023年第5期562-578,共17页
Brain midline delineation can facilitate the clinical evaluation of brain midline shift,which has a pivotal role in the diagnosis and prognosis of various brain pathology.However,there are still challenges for brain m... Brain midline delineation can facilitate the clinical evaluation of brain midline shift,which has a pivotal role in the diagnosis and prognosis of various brain pathology.However,there are still challenges for brain midline delineation:1)the largely deformed midline is hard to localize if mixed with severe cerebral hemorrhage;2)the predicted midlines of recent methods are not smooth and continuous which violates the structural priority.To overcome these challenges,we propose an anisotropic three dimensional(3D)network with context-aware refinement(A3D-CAR)for brain midline modeling.The proposed network fuses 3D context from different two dimensional(2D)slices through asymmetric context fusion.To exploit the elongated structure of the midline,an anisotropic block is designed to balance the difference between the adjacent pixels in the horizontal and vertical directions.For maintaining the structural priority of a brain midline,we present a novel 3D connectivity regular loss(3D CRL)to penalize the disconnectivity between nearby coordinates.Extensive experiments on the CQ dataset and one in-house dataset show that the proposed method outperforms three state-of-the-art methods on four evaluation metrics without excessive computational burden. 展开更多
关键词 brain midline delineation refinement network structure prior connectivity regular loss
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The Atomic Regular Polyhedron Electronic Shell
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作者 Zilong Kong 《Journal of Modern Physics》 2013年第10期1-19,共19页
The periodic table of elements is arranged based on a series of regular polyhedron. The stability of inert gas atoms can be explained by the distribution of electrons, as well as their motion and magnetic force struct... The periodic table of elements is arranged based on a series of regular polyhedron. The stability of inert gas atoms can be explained by the distribution of electrons, as well as their motion and magnetic force structure. A magnetic force regular octahedron is proposed. It is a unique configuration that best satisfies the convergence of electrons moving in the same direction within regular polyhedra. In the case of an electrostatic force crust, the formal electron spin accounts for the crusts intrinsic magnetic moment exceeding the speed of light. If one is to consider that the electron has a magnetic outer layer and an electrostatic inner layer, then the question can be solved and abovementioned inference can provide the basis for magnetic force and momentum for the regular octahedron model. The electron periphery has twenty-petal adsorptive substances;the existence of adsorptive substance causes the magnetic force greater than the electrostatic force. Each electronic shell in the regular polyhedron is in accordance with the electron configuration of periodic table of elements;the kinetic track of each electron is a surface of regular polyhedron. The magnetic properties of iron, cobalt, and nickel can be explained by the regular dodecahedron electronic shell of an atom. The electron orbit converged from reverse direction can explain diamond. The adsorptive substances found in atomic nuclei and electrons are defined as magnetic particles called magnetons. The thermodynamic magneton theory can be better explained when it is analyzed using principles of thermodynamics, superconductivity, viscosity, and even in the creation of glass. The structure of the light is a helical line. 展开更多
关键词 ATOMIC structure regular POLYHEDRON ELECTRONIC SHELL Periodic TABLE of Elements Light Diamond
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Entropy Production in a Non-Isolated Thermodynamic System Taking into Account Regular Factors of Nonrandom Nature
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作者 A. Yu. Khlestkov Yu. A. Khlestkov +2 位作者 N. Yu. Lukashina M. Yu. Lukashin P. Yu. Lukashin 《Journal of Modern Physics》 2020年第3期343-354,共12页
The work illustrates the impossibility of decreasing entropy in a strictly random thermodynamic process in a non-isolated system using the example of heating a planet by solar radiation flux without and taking into ac... The work illustrates the impossibility of decreasing entropy in a strictly random thermodynamic process in a non-isolated system using the example of heating a planet by solar radiation flux without and taking into account its rotation around its own axis. That is, the second law of thermodynamics formulated for isolated systems continues to govern such systems. We have shown that in order to achieve a stationary state at lower values of temperature and entropy far from thermodynamic equilibrium at a maximum of temperature and entropy, it is necessary to have regular factors of nonrandom nature, one of which in this example is the rotation of the planet around its own axis. This means that the reason for the appearance of ordered structured objects in non-isolated thermodynamic systems is not the random process itself, but the action of dynamic control mechanisms, such as periodic external influences, nonlinear elements with positive feedback, catalysts for chemical reactions, etc. We present the plots with dependences of temperature and entropy versus time in non-isolated systems with purely random processes and in the presence of a control factor of non-random nature-rotation. 展开更多
关键词 RANDOM Process Non-Isolated Systems Entropy Ordered structures regular Factors of Non-Random NATURE
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真实世界儿童咳嗽变异性哮喘“药-证-方”探究(5588首)
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作者 于素平 张岩 +6 位作者 任献青 宋桂华 徐炎 张贵春 吕伟刚 彭明浩 邢琼琼 《世界中医药》 北大核心 2025年第17期3130-3136,共7页
目的:基于真实世界探讨儿童咳嗽变异性哮喘(CVA)用药、证型、选方规律,为临床辨治提供“药-证-方”参考。方法:收集河南中医药大学第一附属医院2012年1月1日至2024年1月1日CVA患儿电子病历,构建处方-药物数据库,使用Excel 2021对纳入中... 目的:基于真实世界探讨儿童咳嗽变异性哮喘(CVA)用药、证型、选方规律,为临床辨治提供“药-证-方”参考。方法:收集河南中医药大学第一附属医院2012年1月1日至2024年1月1日CVA患儿电子病历,构建处方-药物数据库,使用Excel 2021对纳入中药进行频数、性能统计;采用SPSS Modeler 18.0与Cytoscape 3.8.0进行关联规则和复杂网络分析,寻找潜在配伍;SPSS Statistics 26.0进行高频中药聚类分析,挖掘潜在证型及组方。结果:纳入5588首中药处方,含299种中药,包含紫菀、款冬花在内26味高频中药,属化痰止咳平喘、解表药类。性能统计得出中药性以寒温、味多苦甘辛,入肝、肺、胃、脾、肾经。关联规则得出紫菀-款冬花在内的5组对药与13组角药为治疗儿童CVA的核心药物组合。聚类得出3组,对应潜在证型为痰热闭肺、痰湿阻滞、风寒束肺证,临床方以五虎汤合葶苈大枣泻肺汤、二陈汤合平胃散、三拗汤合止嗽散为基础。结论:真实世界儿童CVA治疗多用苦温、苦甘辛类药,入肝肺、胃脾、肾经以调理气机升降、化痰止咳平喘。其中紫菀-款冬花等多组对药及角药为治疗儿童CVA的核心组合;痰热闭肺、痰湿阻滞、风寒束肺反映真实世界常见中医证型。 展开更多
关键词 真实世界 隐结构 关联规则 聚类分析 儿童 咳嗽变异性哮喘 药-证-方 用药规律
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黔南半边街-竹林沟锌锗矿床构造解析及其成矿意义
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作者 杨旭 杨亚琦 +6 位作者 黄智龙 曹鹏 薛忠喜 卢贸达 肖凯 衮民汕 赵兴华 《矿物学报》 北大核心 2025年第3期468-484,共17页
黔南地区位于扬子克拉通东南缘,发育大量铅锌矿床,是湘西–黔东铅锌成矿带的重要组成部分。贵定半边街–竹林沟锌锗矿床是一个中型的锌矿床,锗资源量可达特大型规模,其矿体受构造和岩性控制明显。矿区内构造变形复杂多样,但构造控矿规... 黔南地区位于扬子克拉通东南缘,发育大量铅锌矿床,是湘西–黔东铅锌成矿带的重要组成部分。贵定半边街–竹林沟锌锗矿床是一个中型的锌矿床,锗资源量可达特大型规模,其矿体受构造和岩性控制明显。矿区内构造变形复杂多样,但构造控矿规律尚不明确,严重制约了对成矿过程的理解和下一步的找矿方向。详细的野外地质勘查和构造解析表明,矿区至少经历3期明显的构造变形。D_(1)为NNE–SSW向缩短形成北西-南东向逆冲断层(兼右行走滑)活动,伴随着断层上下盘的牵引褶皱及层间滑动等;D_(2)为NW–SE向到NWW–SEE向的缩短变形,形成区域上典型隔槽式褶皱和近南北向的逆断层;D_(3)为近S–N向的伸展作用,使得矿区内北西-南东向断层发生明显的伸展变形并伴生大量不同规模的共轭节理。不同矿段矿体特征显示:矿体受控于上泥盆统高孔隙度的白云岩地层,由大量切层、顺层矿脉以及少量切层矿体组成。构造角砾岩容矿矿体和切层矿脉的几何学、运动学特征以及矿体围岩的剪切变形表明,容矿构造可能是NNE–SSW向缩短变形的结果,与MVT型铅锌矿床构造特征基本一致。通过对深部物探剖面和地表构造的解析,本文重建了矿区成矿期深部构造控矿样式,初步拟定F4断层上下盘望城坡组地层可能是成矿潜力区。半边街–竹林沟锌锗矿床与黔南及邻区铅锌矿床具有相似的岩性-构造特征,其控矿构造模型对于区域内铅锌矿的找矿勘查具有指导意义。 展开更多
关键词 湘西–黔东成矿带 锌锗矿床 构造解析 成矿规律
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基于降水测量卫星的中国降水系统特征及其对流天气研究
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作者 陈浩 陈凤娇 +4 位作者 诸葛小勇 唐飞 姚彬 阚琬琳 宇路 《大气科学学报》 北大核心 2025年第6期990-1003,共14页
系统总结了近20年来利用降水测量卫星研究中国降水系统特征的主要进展。首先,概述了三种降水测量卫星的主要观测设备及其参数,并分析了它们在观测降水系统方面的优势和局限性。接着,回顾了当前用于实现降水系统参数化的主要方法,重点归... 系统总结了近20年来利用降水测量卫星研究中国降水系统特征的主要进展。首先,概述了三种降水测量卫星的主要观测设备及其参数,并分析了它们在观测降水系统方面的优势和局限性。接着,回顾了当前用于实现降水系统参数化的主要方法,重点归纳了中国降水系统的活动规律和结构特征,包括其随季节、地区、天气系统以及降水系统自身的组织形态和生命阶段所表现的变化规律。最后,阐述了闪电、极端降水等强对流天气与降水系统三维结构及微物理过程之间的关联。在此基础上,梳理了当前与未来利用降水测量卫星研究降水系统所面临的机遇与挑战,并展望了该领域未来的潜在发展方向。 展开更多
关键词 降水测量卫星 降水系统 活动规律 结构特征 对流天气
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