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Toward understanding the role of genomic repeat elements in neurodegenerative diseases
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作者 Zhengyu An Aidi Jiang Jingqi Chen 《Neural Regeneration Research》 SCIE CAS 2025年第3期646-659,共14页
Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage se... Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements. 展开更多
关键词 Alzheimer's disease ATAXIA deep learning long-read sequencing NEURODEGENERATION neurodegenerative diseases Parkinson's disease repeat element structural variant
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SMART STRUCTURES USING PIEZOELEMENTS FOR ACTIVE VIBRATION AND NOISE SUPPRESSION IN AVIATION AND AEROSPACE 被引量:1
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作者 陈仁文 陶宝祺 +1 位作者 陈勇 朱晓锦 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期39-44,共6页
Smart material and structure (SMS) is a challenging novel technique for the 21 century especially in fields of aviation and aerospace. Vibration and noise suppression smart structure is an important branch of SMS. T... Smart material and structure (SMS) is a challenging novel technique for the 21 century especially in fields of aviation and aerospace. Vibration and noise suppression smart structure is an important branch of SMS. There are several typical structures such as the cabin of an airplane, space station, the solar board of satellite and the rotor blade of a helicopter, of which the vibrations and radiation noises have bad influences on precise equipments and aiming systems. In order to suppress vibrations and noises of these structures, several algorithms are applied to the models which simulate the structures. Experiments are performed to suppress vibrations and noises by bonding sensors and actuators to the structures at the optimized locations and using computer based measurement and control systems. For the blade vibration control of a helicopter, a non contact method of signal transmission by magneto electric coupling is discussed. The experimental results demonstrate that the methods used for active control are effective. 展开更多
关键词 VIBRATION active control smart structure piezoceramic element noise suppression test and measurement system
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Effects of Surface-Active Elements Sulfur on Flow Patterns of Welding Pool 被引量:3
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作者 Yuzhen ZHAO, Yongping LEI and Yaowu SHI School of Materials Science and Engineering, Beijing University of Technology, Beijing 100022, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第3期408-414,共7页
A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc (GTA) welding pool with different sulfur concentrations. It has been shown that, the weld penet... A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc (GTA) welding pool with different sulfur concentrations. It has been shown that, the weld penetration increases sharply with increasing sulfur content. When sulfur content increases beyond 80 × 10-6, the increase in sulfur content does not have an appreciable difference on the welding pool size and shape, and the depth/width remains constant. Sulfur changes the temperature dependence of surface tension coefficient from a negative value to a positive value and causes significant changes on flow patterns. The increase in soluble sulfur content and the decrease at free surface temperature can extend the region of positive surface tension coefficient. As sulfur content exceeds 125×10-6, the sign of surface tension coefficient is positive. Depending upon the sulfur concentrations, three, one or two vortexes that have different positions, strength and directions may be found in the welding pool. The contrary vortexes can efficiently transfer the thermal energy from the arc, creating a deep welding pool. An optimum range of sulfur content is 20-150×10-6. 展开更多
关键词 Surface-active elements SULFUR Plow patterns Depth/width
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Numerical analysis of behavior of active layer in rotary kilns by discrete element method 被引量:3
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作者 谢知音 冯俊小 《Journal of Central South University》 SCIE EI CAS 2013年第3期634-639,共6页
The behavior of the active layer of material bed within rotary kilns plays a key role in industrial applications.To obtain its influences on industrial process,different regimes of particle motion have been simulated ... The behavior of the active layer of material bed within rotary kilns plays a key role in industrial applications.To obtain its influences on industrial process,different regimes of particle motion have been simulated by discrete element method(DEM) in three dimensions under variant rotation speeds,filling degree,based on the background of induration process of iron ore pellets.The influences of the mentioned factors on the maximum thickness of the active layer and the average velocity of particles have been investigated.The average velocity of particles increases with Froude number following the power function over a wide range,and the maximum thickness rises with increasing rotation speed in a way of logarithm.The influence of the filling degree f on the maximum thickness exhibits a good linearity under two classic regimes,but the increasing of the average velocity of the active layer is limited at f=0.4.This basic research highlights the impact of the active layer within rotary kilns,and lays a good foundation for the further investigation in mixing and heat transfer within the particle bed inside rotary kilns. 展开更多
关键词 rotary kiln particle motion discrete element method active layer
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Active Vibration Control of a Railway Vehicle Carbody Using Piezoelectric Elements 被引量:1
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作者 Habibollah Molatefi Pejman Ayoubi Hozhabr Mozafari 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期963-972,共10页
In recent years and according to modem trans- portation development, rail vehicles are manufactured lighter to achieve higher speed and lower transportation costs. On the other hand, weight reduction of rail vehicles ... In recent years and according to modem trans- portation development, rail vehicles are manufactured lighter to achieve higher speed and lower transportation costs. On the other hand, weight reduction of rail vehicles leads to increase the structural vibration. In this study, Active Vibration Control of a rail vehicle using piezo- electric elements is investigated. The optimal control employed as the control approach regard to the first two modes of vibration. A simplified Car body structure is modeled in Matlab using the finite element theory by considering six DOF beam element and then the Eigen functions and mode shapes are derived. The surface roughness of different classes of rail tracks have been obtained using random vibration theory and applied to the secondary suspension as the excitation of the structure; Then piezoelectric mounted where the greatest moments were captured. The effectiveness of Piezoelectric in structural vibrations attenuation of car body is demon- strated through the state space equations and its effect on modal coefficient. 展开更多
关键词 active vibrationRandom vibrations Modalmethodcontrol PIEZOELECTRIC ANALYSIS Finite element
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A DYNAMIC BOX MODEL OF BIOACTIVE ELEMENTS IN THE SOUTHERN TAIWAN STRAIT 被引量:4
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作者 洪华生 商少凌 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1994年第2期120-129,共10页
A dynamic box model was applied to study the characteristics of biogeochemical cycling of PO<sub>4</sub>-P,NO<sub>3</sub>-N,AOU,POC and PON in the southern Taiwan Strait region based on field d... A dynamic box model was applied to study the characteristics of biogeochemical cycling of PO<sub>4</sub>-P,NO<sub>3</sub>-N,AOU,POC and PON in the southern Taiwan Strait region based on field data of the"Minnan Taiwan Bank Fishing Ground Upwelling Ecosystem Study" during the period of Dec.1987-Nov.1988.According to the unique hydrological and topographical features of the region,six boxesand three layers were considered in the model.The variation rates and fluxes of elements induced by hor-izontal current,upwelling,by diffusion,sinking of particles and biogeochemical processes were estimatedrespectively.Results further confirmed that upwellings had important effects in this region.Thenearshore upwelling areas had net input fluxes of nutrients brought by upwelling water,also had high de-pletion rates of nutrients and production rates of particulate organic matter and dissolved oxygen.Theabnormal net production of nutrients in the middle layer(10-30m) indicated the important role of bacte-ria in this high production region. 展开更多
关键词 BOX model bioactive elementS PARTICULATE ORGANIC carbon FLUX UPWELLING
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A Study on Modular Fixture Design with Intelligent Selection of Elements and Interactive Assembly 被引量:3
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作者 刘文剑 黄永强 常伟 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第4期45-48,共4页
Based on the features of the design and assembly of rnodular fixtures, a new design system which combines intelligent selection of elements and interactive assembly is presented.Using the fixture design datum, the sys... Based on the features of the design and assembly of rnodular fixtures, a new design system which combines intelligent selection of elements and interactive assembly is presented.Using the fixture design datum, the system can automatically select elements,and can interactively assemble together these elements based on AutoCAD. An example is given to illustrate it. 展开更多
关键词 ss: MODULAR FIXTURE expert system INTELLIGENT selection of elementS INTERactive ASSEMBLY
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“ACTIVE”英语学科育人模式构建与应用
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作者 庞晖 杨璐 《现代教育》 2024年第12期22-27,共6页
本研究以“立德树人”为核心理念,构建“ACTIVE”英语学科育人模式。该模式通过六个关键维度--学科育人(AIM)、文化浸润(Culture)、思维可见(Thinking)、技术融合(Integration)、美德根植(Virtue)和情感共鸣(Empathy)--全面激发学生英... 本研究以“立德树人”为核心理念,构建“ACTIVE”英语学科育人模式。该模式通过六个关键维度--学科育人(AIM)、文化浸润(Culture)、思维可见(Thinking)、技术融合(Integration)、美德根植(Virtue)和情感共鸣(Empathy)--全面激发学生英语学习的热情,培养他们的语言能力,同时注重道德品质的熏陶和文化素养的提升,促进英语学科素养落地。本研究不仅为英语教学实践提供了新的视角,也为其他学科育人模式的构建提供了有益的参考和借鉴。 展开更多
关键词 英语教学 学科育人 active 育人模式
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A B-spline active contour model based on finite element method 被引量:1
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作者 成思源 《Journal of Chongqing University》 CAS 2003年第1期62-65,共4页
A B-spline active contour model based on finite element method is presented, into which the advantages of a B-spline active contour attributing to its fewer parameters and its smoothness is built accompanied with redu... A B-spline active contour model based on finite element method is presented, into which the advantages of a B-spline active contour attributing to its fewer parameters and its smoothness is built accompanied with reduced computational complexity and better numerical stability resulted from the finite element method. In this model, a cubic B-spline segment is taken as an element, and the finite element method is adopted to solve the energy minimization problem of the B-spline active contour, thus to implement image segmentation. Experiment results verify that this method is efficient for B-spline active contour, which attains stable, accurate and faster convergence. 展开更多
关键词 active contour mode B-SPLINE finite element method
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Realizing high photovoltaic efficiency with parallel multijunction solar cells based on spectrum-splitting and-concentrating diffractive optical element 被引量:1
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作者 王进泽 黄庆礼 +7 位作者 许信 全宝钢 罗建恒 张岩 叶佳声 李冬梅 孟庆波 杨国桢 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期329-334,共6页
Based on the facts that multijunction solar cells can increase the efficiency and concentration can reduce the cost dramatically, a special design of parallel multijunction solar cells was presented. The design employ... Based on the facts that multijunction solar cells can increase the efficiency and concentration can reduce the cost dramatically, a special design of parallel multijunction solar cells was presented. The design employed a diffractive optical element (DOE) to split and concentrate the sunlight. A rainbow region and a zero-order diffraction region were generated on the output plane where solar cells with corresponding band gaps were placed. An analytical expression of the light intensity distribution on the output plane of the special DOE was deduced, and the limiting photovoltaic efficiency of such parallel multijunction solar ceils was obtained based on Shockley-Queisser's theory. An efficiency exceeding the Shockley--Queisser limit (33%) can be expected using multijunction solar cells consisting of separately fabricated subcells. The results provide an important alternative approach to realize high photovoltaic efficiency without the need for expensive epitaxial technology widely used in tandem solar cells, thus stimulating the research and application of high efficiency and low cost solar cells. 展开更多
关键词 diffractive optical element SPLIT CONCENTRATION MULTIJUNCTION
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TRACTIVE PERFORMANCE ANALYSIS ON RADIALLY DEPLOYABLE WHEEL CONFIGURATION OF LUNAR ROVER VEHICLE BY DISCRETE ELEMENT METHOD 被引量:8
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作者 LI Wen GAO Feng JIA Yang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第5期13-18,共6页
With the consideration of volume constraint of launch vehicle and trafficability of rover vehicle on lunar regolith terrain, a new design of radially deployable wheel is presented. For the purpose of achieving the mes... With the consideration of volume constraint of launch vehicle and trafficability of rover vehicle on lunar regolith terrain, a new design of radially deployable wheel is presented. For the purpose of achieving the meso-mechanics and dynamical behavior of lunar soil particles as well as macro-parameters of tractive performance for radially deployable wheel, the interaction between two types of wheel configurations and lunar soil particles is analyzed by means of discrete element method. The network of contact forces, the displacement vector chart, and the deformation of lunar soil beneath wheels are plotted. The equations of soil thrust, motion resistance, drawbar pull and driven torque are derived in granular scale based on the coordinates transformation and algebraic summation. The calculated results show that there is sufficient traction for both 6-split and 12-split radially deployable wheels with 304 mm outspread diameter to negotiate lunar regolith terrain specified here; the value of drawbar pull enhances with the increase of split number of radially deployable wheel, however, the required driven torque increases simultaneously, therefore, the tractive efficiency decreases. 展开更多
关键词 Radially deployable wheel Discrete element method Tractive performance Trafficability Lunar regolith
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Current state of active trachoma among elementary school students in the context of ambitious national growth plan: The case of Ethiopia 被引量:2
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作者 Molla Gedefaw Ali Shiferaw +3 位作者 Zelalem Alamrew Amsalu Feleke Tsegaw Fentie Kiros Atnafu 《Health》 2013年第11期1768-1773,共6页
Trachoma is a classical disease of poverty. It is still the second leading cause of blindness in Ethiopia. Cognizant of the poor living condition of its people, every effort of the current government of Ethiopia is ge... Trachoma is a classical disease of poverty. It is still the second leading cause of blindness in Ethiopia. Cognizant of the poor living condition of its people, every effort of the current government of Ethiopia is geared towards eradication of extreme poverty. The main aim of this study was to assess the current status and correlates of active trachoma among elementary school students. A cross sectional school-based study was conducted in Dangla town administration in the month of March 2012. Multistage sampling technique was employed. Pre-tested structured questionnaire and eye examination were data collection tools. The data were collected by health professionals especially trained for eye care. The data were analyzed using SPSS version 16 for windows. Possible associations, and statistical significance between, and among variables were measured using odds ratio at 95% confidence interval. The study indicated that overall prevalence of active trachoma was 12%. The multi-variate analysis revealed that those children with unclean face were seven times more likely to develop active trachoma than those with clean face (AOR = 7.07, 95% CI: 3.36-14.96). Moreover, children who didn’t use soap to wash their face were two times more likely to develop active trachoma than those who claimed to use soap to wash their face (AOR = 2.03, 95% CI 1.72-3.01). In short, the prevalence of trachoma is lower than the figures in previous survey reports in the region and at national levels;however, the risk factors remain the same. The struggle to eradicate extreme poverty should continue in a sustainable manner so that diseases of poverty including trachoma could be eliminated altogether. 展开更多
关键词 active TRACHOMA SCHOOL Children NATIONAL PLAN Ethiopia
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Simple and universal method in designs of high-efficiency diffractive optical elements for spectrum separation and beam concentration 被引量:2
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作者 徐文琪 林冬风 +8 位作者 许信 叶佳声 王新柯 冯胜飞 孙文峰 韩鹏 张岩 孟庆波 杨国桢 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期89-95,共7页
Diffractive optical elements(DOEs) with spectrum separation and beam concentration(SSBC) functions have important applications in solar cell systems. With the SSBC DOEs, the sunlight radiation is divided into seve... Diffractive optical elements(DOEs) with spectrum separation and beam concentration(SSBC) functions have important applications in solar cell systems. With the SSBC DOEs, the sunlight radiation is divided into several wave bands so as to be effectively absorbed by photovoltaic materials with different band gaps. A new method is proposed for designing high-efficiency SSBC DOEs, which is physically simple, numerically fast, and universally applicable. The SSBC DOEs are designed by the new design method, and their performances are analyzed by the Fresnel diffraction integral method.The new design method takes two advantages over the previous design method. Firstly, the optical focusing efficiency is heightened by up to 10%. Secondly, focal positions of all the designed wavelengths can be designated arbitrarily and independently. It is believed that the designed SSBC DOEs should have practical applications to solar cell systems. 展开更多
关键词 diffractive optical element spectrum separation and beam concentration optical focusing efficiency solar cell system
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A single diffractive optical element implementing spectrum-splitting and beam-concentration functions simultaneously with high diffraction efficiency 被引量:2
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作者 叶佳声 王进泽 +3 位作者 黄庆礼 董碧珍 张岩 杨国桢 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期44-49,共6页
In this paper,a novel method is proposed and employed to design a single diffractive optical element(DOE) for implementing spectrum-splitting and beam-concentration(SSBC) functions simultaneously.We develop an opt... In this paper,a novel method is proposed and employed to design a single diffractive optical element(DOE) for implementing spectrum-splitting and beam-concentration(SSBC) functions simultaneously.We develop an optimization algorithm,through which the SSBC DOE can be optimized within an arbitrary thickness range according to the limitations of modern photolithography technology.Theoretical simulation results reveal that the designed SSBC DOE has a high optical focusing efficiency.It is expected that the designed SSBC DOE should have practical applications in high-efficiency solar cell systems. 展开更多
关键词 diffractive optical element spectrum-splitting and beam-concentration functions thickness optimization algorithm solar cell systems
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The Problem of Natural Radioactive Elements 被引量:2
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作者 Andrzej Pawuła 《Journal of Geoscience and Environment Protection》 2021年第4期176-194,共19页
The article presents two opposing views on the origin of natural radioactive elements. According to a view based on the Big Bang Theory, the elements found on Earth were formed by the process of primary nucleosyntase ... The article presents two opposing views on the origin of natural radioactive elements. According to a view based on the Big Bang Theory, the elements found on Earth were formed by the process of primary nucleosyntase 13.8 billion years ago, with the exception of uranium and other heavy elements that were formed billions of years later under stellar conditions. It follows from this view that throughout the existence of the earth, the global amount of uranium and other primary radionuclides is reduced as a result of natural decay. The reasoning of the proponents of the BB theory is as follows: if the global radioactivity decreases, the problem of the threat decreases and one only needs to get used to the newly discovered natural phenomenon. There are even official regulations that exclude ionizing radiation from radon in the calculation of the limit dose. The Primary Forces of Nature theory presents a completely different view. Considering the analogous influence of gravity on the formation of the globs of the solar system, the logical explanation of the phenomena of geological activity are thermonuclear processes, such as on the sun. Hence the conclusion that the elements chemical are now created in the core of the Earth in the process of thermonuclear synthesis. The problem is serious because there is an accelerated growth of new igneous matter containing the created elements, and the ionizing radiation of natural radionuclides is the main factor responsible for the radioactivity level of the human environment. 展开更多
关键词 Radioactive elements Uranium Geology RADIOECOLOGY RADON
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EFFECTS OF ACTIVE ELEMENTS Y AND Ce ON HIGH TEMPERATURE OXIDATION OF Fe-25Cr-40Ni ALLOY
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作者 YU Fanghua YANG Guohua Shanghai Institute of Nuclear Research,Academia Sinica,Shanghai,ChinaHAN Rongdian WENG Huimin University of Science and Technology of China,Hefei,ChinaSHEN Jianian Corrosion Science Laboratory,Institute of Corrosion and Protection of Metals Academia Sinica,Shenvang,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1992年第11期383-390,共8页
The effects of small amount(≥0.05%)of active elements Y and Ce in Fe-25Cr-40Ni al- loy have been investigated on the kinetics of early stage of high temperature oxidation as well as composition and microsructure of o... The effects of small amount(≥0.05%)of active elements Y and Ce in Fe-25Cr-40Ni al- loy have been investigated on the kinetics of early stage of high temperature oxidation as well as composition and microsructure of oxide film by ion backscattering and slow positron beam.The results show that Y and Ce can reduce evidently the high tem- perature oxidation rate of FeCrNi alloy at early stage and can effectively enhance the Cr_2O_3 formation and retard the oxide formation of Fe and Ni in the surface layer thus the microstructure of the oxide film is improved.Y and Ce enter the oxide film and concentrate within several tens nanometres from surface of the outer layer.The mech- anism of oxidation resistance for Ce is different from Y.Ce can decrease the density of vacancy defects in oxide layer,so the cations are restrained from diffusion outward through vacancies.While Y can control the outward diffusion of cations through va- cancies at the early statge of oxidation(shorter than 12 min),aften that restrained the cations from diffusion outward along grain boundaries up to 60 min oxidation. 展开更多
关键词 ion backscattering slow positron beam OXIDATION active elements FeCrNi alloy
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LiToTac: An Interactive-Interface Software for Finite Element Analysis of Multiple Contact Dynamics 被引量:4
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作者 Lei Peng Zhiqiang Feng +1 位作者 Pierre Joli Christine Renaud 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第1期111-137,共27页
In order to investigate the mechanical behavior of systems with complex architecture and a large number of contacting bodies,a finite element software,named LiToTac,has been developed by using the object-oriented prog... In order to investigate the mechanical behavior of systems with complex architecture and a large number of contacting bodies,a finite element software,named LiToTac,has been developed by using the object-oriented programming technique.This software,with an interactive graphical user interface,is able to handle highly non-linear problems including multiple contacts and large deformation.More importantly,the contact detection based on a hybrid three-stages methodology can be performed automatically,which is more efficient than the common strategies of pre-defining contact zones in commercial FEM software like ANSYS,ABAQUS,etc.In addition,the contact solver in LiToTac is portable between dynamic and quasi-static codes and can accurately solve contact coupled with friction in a reduced system.Several numerical examples are carried out to illustrate the functionality and capacity of the software package. 展开更多
关键词 FINITE element software OBJECT-ORIENTED PROGRAMMING automatic CONTACT detection MULTIPLE CONTACT dynamics.
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Design and Implementation of An Active Multibeam Antenna System with 64 RF Channels and 256 Antenna Elements for Massive MIMO Application in 5G Wireless Communications 被引量:4
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作者 PANG Xingdong HONG Wei YANG Tianyang LI Linsheng 《China Communications》 SCIE CSCD 2014年第11期16-23,共8页
This paper focuses on the design and implementation of an active multibeam antenna system for massive MIMO applications in 5G wireless communications.The highly integrated active multibeam antenna system is designed a... This paper focuses on the design and implementation of an active multibeam antenna system for massive MIMO applications in 5G wireless communications.The highly integrated active multibeam antenna system is designed and implemented at 5.8 GHz with 64 RF Channels and 256 antenna elements.The 64-channel highly integrated active multibeam antenna system provides a verification platform for digital beamforming algorithm and massive MIMO channel estimation for next generation wireless communications. 展开更多
关键词 5G active multibeam antenna system digital beamforming Massive MIMO 5G wireless communications
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THE BACKGROUND VALUES OF RARE EARTH AND RADIOACTIVE ELEMENTS IN WATER SYSTEM OF SOURCE AREA OF THE CHANG JIANG RIVER
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作者 张立诚 周克俊 +1 位作者 钱杏珍 李岫霞 《Chinese Geographical Science》 SCIE CSCD 1993年第3期74-85,共12页
Using neutron activation analysis method we determined contents of rare-earth and radioactive elements (La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Cs, Rb, Sb, Sc, Sr, Ba, U, Th) in source water system of the Changjiang (Yangtze)... Using neutron activation analysis method we determined contents of rare-earth and radioactive elements (La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Cs, Rb, Sb, Sc, Sr, Ba, U, Th) in source water system of the Changjiang (Yangtze) River, which is mainly composed of the Tuotuo River, the Chumaer River, and the Buqu River. The contents of these elements in the unflltered water have a great variation and a close correlation with the water turbidity. The contents of these elements in filtered water only have a little variation and are lower than those in the unflltered water. The variations in contents of these elements in sediments are also very little. These elements in the unifiltered water are in geometric distribution, except Sc. Most of the elements in sediments are in arithmetic distribution, but Cs, Sb, Th, are in deviation distribution. The contents of most of these elements in the river source area correspond to the contents of fresh water of the earth. Most of these elements have a little variation in their 展开更多
关键词 source area of the CHANGJIANG RIVER background value RADIOactive elements neutron activation analysis method
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Effects of Yibei multi-active elements on mesenteric microcirculation in rats
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作者 SHAO BoQin1, SHI YiJu2, LIU Sai1, ZHANG Jian1 and GUO JinTai1 《World Journal of Gastroenterology》 SCIE CAS CSCD 1998年第3期93-94,共2页
fectsofYibeimultiactiveelementsonmesentericmicrocirculationinratsSHAOBooQin1,SHIYiJu2,LIUSai1,ZHANGJian1a... fectsofYibeimultiactiveelementsonmesentericmicrocirculationinratsSHAOBooQin1,SHIYiJu2,LIUSai1,ZHANGJian1andGUOJinTai1Subj... 展开更多
关键词 MICROCIRCULATION MESENTERY Yibei multiactive elementS (YBMAE) BLOOD flow velocity
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