期刊文献+
共找到160,331篇文章
< 1 2 250 >
每页显示 20 50 100
Translocation of telomerase reverse transcriptase coincided with ATP release in postnatal cochlear supporting cells 被引量:1
1
作者 Yukai Zhang Keyong Tian +9 位作者 Wei Wei Wenjuan Mi Fei Lu Zhenzhen Liu Qingwen Zhu Xinyu Zhang Panling Geng Jianhua Qiu Yongli Song Dingjun Zha 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1119-1125,共7页
The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechani... The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechanisms responsible for initiating spontaneous ATP release have not been determined.Our previous study revealed that telomerase reverse transcriptase(TERT)is expressed in the basilar membrane during the first postnatal week.Its role in cochlear development remains unclear.In this study,we investigated the expression and role of TERT in postnatal cochlea supporting cells.Our results revealed that in postnatal cochlear Kölliker’s organ supporting cells,TERT shifts from the nucleus into the cytoplasm over time.We found that the TERT translocation tendency in postnatal cochlear supporting cells in vitro coincided with that observed in vivo.Further analysis showed that TERT in the cytoplasm was mainly located in mitochondria in the absence of oxidative stress or apoptosis,suggesting that TERT in mitochondria plays roles other than antioxidant or anti-apoptotic functions.We observed increased ATP synthesis,release and activation of purine signaling systems in supporting cells during the first 10 postnatal days.The phenomenon that TERT translocation coincided with changes in ATP synthesis,release and activation of the purine signaling system in postnatal cochlear supporting cells suggested that TERT may be involved in regulating ATP release and activation of the purine signaling system.Our study provides a new research direction for exploring the spontaneous electrical activity of the cochlea during the early postnatal period. 展开更多
关键词 apoptosis ATP release Ca2+transients COCHLEA mitochondrial function reactive oxygen species spontaneous electrical activity supporting cells
下载PDF
Meter-Scale Thin-Walled Structure with Lattice Infill for Fuel Tank Supporting Component of Satellite:Multiscale Design and Experimental Verification
2
作者 Xiaoyu Zhang Huizhong Zeng +6 位作者 Shaohui Zhang Yan Zhang Mi Xiao Liping Liu Hao Zhou Hongyou Chai Liang Gao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期201-220,共20页
Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be f... Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be fabricated bymetallic additive manufacturing technique,such as selective laser melting(SLM).However,the maximum dimensions of actual structures are usually in a sub-meter scale,which results in restrictions on their appliance in aerospace and other fields.In this work,a meter-scale thin-walled structure with lattice infill is designed for the fuel tank supporting component of the satellite by integrating a self-supporting lattice into the thickness optimization of the thin-wall.The designed structure is fabricated by SLM of AlSi10Mg and cold metal transfer welding technique.Quasi-static mechanical tests and vibration tests are both conducted to verify the mechanical strength of the designed large-scale lattice thin-walled structure.The experimental results indicate that themeter-scale thin-walled structure with lattice infill could meet the dimension and lightweight requirements of most spacecrafts. 展开更多
关键词 Thin-walled structure lattice infill supporting component selective laser melting SATELLITE
下载PDF
Experimental and Numerical Investigation on the Aerodynamic Characteristics of High-Speed Pantographs with Supporting Beam Wind Deflectors
3
作者 Shiyang Song Tongxin Han 《Fluid Dynamics & Materials Processing》 EI 2024年第1期127-145,共19页
Aiming to mitigate the aerodynamic lift force imbalance between pantograph strips,which exacerbates wear and affects the current collection performance of the pantograph-catenary system,a study has been conducted to s... Aiming to mitigate the aerodynamic lift force imbalance between pantograph strips,which exacerbates wear and affects the current collection performance of the pantograph-catenary system,a study has been conducted to support the beam deflector optimization using a combination of experimental measurements and computational fluid dynamics(CFD)simulations.The results demonstrate that the size,position,and installation orientation of the wind deflectors significantly influence the amount of force compensation.They also indicate that the front strip deflectors should be installed downwards and the rear strip deflectors upwards,thereby forming a“π”shape.Moreover,the lift force compensation provided by the wind deflectors increases with the size of the deflector.Alternative wind compensation strategies,such as control circuits,are also discussed,putting emphasis on the pros and cons of various pantograph types and wind compensation approaches. 展开更多
关键词 High-speed pantograph aerodynamic lift force supporting beam wind deflectors computational fluid dynamics(CFD)
下载PDF
Science and Technology Commissioners Supporting High-Quality Development Project for Hundreds of Counties, Thousands of Towns, and Myriads of Villages in the Context of Rural Revitalization
4
作者 Wenwen WEI Cuihong YANG Xiguang ZHU 《Asian Agricultural Research》 2024年第4期1-2,7,共3页
This paper discusses the important role of science and technology commissioners in the high-quality development of hundreds of counties,thousands of towns,and myriads of villages in the context of rural revitalization... This paper discusses the important role of science and technology commissioners in the high-quality development of hundreds of counties,thousands of towns,and myriads of villages in the context of rural revitalization,including building bridges,accelerating the transformation of achievements,promoting the value-added of the whole agricultural industry chain,and promoting the rapid development of rural industrial economy.It also discusses the working achievements of science and technology commissioners,in order to promote further development of rural revitalization in Guangdong Province. 展开更多
关键词 SCIENCE and TECHNOLOGY COMMISSIONERS Hundreds of counties thousands of TOWNS and myriads of VILLAGES SCIENCE and TECHNOLOGY support
下载PDF
Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn‑Air Batteries
5
作者 Xiaohong Zou Qian Lu +8 位作者 Mingcong Tang Jie Wu Kouer Zhang Wenzhi Li Yunxia Hu Xiaomin Xu Xiao Zhang Zongping Shao Liang An 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期176-190,共15页
Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3... Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe oxide.It is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe oxide.Considering the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts. 展开更多
关键词 Catalyst-support interaction supported catalysts HETEROINTERFACE Oxygen evolution reaction Zn-air batteries
下载PDF
Teachers’ Perceptions of the Challenges and Strategies in Supporting Students with Reading Difficulties
6
作者 Kristel P.Alcayde Ma.Leticia Jose C.Basilan 《Journal of Contemporary Educational Research》 2024年第8期238-252,共15页
The purpose of this study is to determine the teacher’s perceptions of the challenges and strategies in supporting students with reading difficulties.This study used qualitative method of research and descriptive app... The purpose of this study is to determine the teacher’s perceptions of the challenges and strategies in supporting students with reading difficulties.This study used qualitative method of research and descriptive approach as its research design,in addition to a set of structured interview questions administered through Google Forms to gather data from elementary teachers of Taal Central School,located at Taal Batangas.These structured interview questions were carefully designed to cover various dimensions of the study,including the types of challenges perceived by teachers,strategies employed,and possible solutions for addressing the problems encountered in the process of supporting students with reading difficulties.The results revealed that teachers faced several challenges when teaching students with reading difficulties such as emotional and motivational issues/factors,lack of resources or teaching aids,deficits in knowledge and skills,and problems with student engagement and participation.This study also showed common approaches utilized by the teachers in supporting students with reading difficulties,which were fostering a positive and supportive environment,adopting individualized and multifaceted approaches,and utilizing effective teaching tools and strategies.Lastly,teachers also concluded varied solutions in addressing the challenges perceived in teaching students with reading difficulties towards fostering reading proficiency.These include developing peer support,use of positive reinforcement,and parental involvement.Moreover,specialized resources,professional development for teachers,and specific teaching strategies are also highlighted as crucial components.By integrating these approaches,teachers concluded that it can create a supportive and effective learning environment tailored to the needs of students with reading difficulties. 展开更多
关键词 Reading difficulties supportive environment Positive reinforcement Parental involvement Professional development
下载PDF
Corroborative Activities and Recognition Between Community Comprehensive Care Unit’s Nurses and Care Managers in Supporting Discharge of Elderly from Hospital - A Secondary Publication
7
作者 Yukie Sakamoto Shizuko Omote +2 位作者 Rie Okamoto Yutaro Takahashi Satomi Ikeuchi 《Journal of Clinical and Nursing Research》 2024年第4期381-392,共12页
Objective: The purpose of this study was to clarify the collaborative activities and mutual recognition between community comprehensive care unit nurses (Ns) and care managers (CM) in supporting the discharge of the e... Objective: The purpose of this study was to clarify the collaborative activities and mutual recognition between community comprehensive care unit nurses (Ns) and care managers (CM) in supporting the discharge of the elderly from the hospital. Methods: A total of 300 nurses working in community comprehensive care wards and 360 care managers working in B City in A Prefecture were surveyed using an anonymous self-administered questionnaire. Results: The highest percentage of responses regarding necessary collaborative activities with multiple professions in supporting hospital discharge were the same for Ns and CMs. The items regarding practice with the highest percentages were “relationship as a team” for Ns, and “user-centered awareness” for CM. While these professionals were willing to share information about their patients’ lives after discharge, the percentage of those explaining their expertise was low. It is thought that collaborative activities focusing on these aspects would lead to more appropriate discharge support. 展开更多
关键词 Discharge support Community comprehensive care ward Ward nurses Care managers Collaborative activities
下载PDF
基于Supporting-Ellipsoid方法的自由曲面构造 被引量:3
8
作者 顾国超 刘洪波 +1 位作者 陈家奇 高雁 《中国光学》 EI CAS 2014年第5期823-829,共7页
为了在特定平面上获得任意形式的辐照分布,采用了Supporting-Ellipsoid设计方法来构造自由曲面反射镜。介绍了其设计思想和设计过程,并以具体的设计实例为例构建了自由曲面光学系统。仿真结果表明,在不计反射损失的情况下,系统效率达到... 为了在特定平面上获得任意形式的辐照分布,采用了Supporting-Ellipsoid设计方法来构造自由曲面反射镜。介绍了其设计思想和设计过程,并以具体的设计实例为例构建了自由曲面光学系统。仿真结果表明,在不计反射损失的情况下,系统效率达到了97%,较传统太阳模拟器光学系统提升了3倍以上,不均匀度达到5.26%,与理想状态有一定差距,这是因为设计中兼顾了计算时间和自由曲面光滑性所造成的。 展开更多
关键词 supporting-Ellipsoid方法 自由曲面 均匀照明
下载PDF
Study on Repairing Permanent Transportation Roadway in Deep Mining by Bolt-Shotcrete and Mesh Supporting 被引量:10
9
作者 宋宏伟 鹿守敏 《International Journal of Mining Science and Technology》 SCIE EI 1999年第2期167-171,共5页
The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production... The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production performance and safety. Based on analysis of supporting objects for roadway repairing, this paper proposes the supporting parameters and condruction technics. The industrial ted of 70m long roadway repairing shows that the proposed parameters and technics of bolt shotcrete and mesh support for roadway repairing are reasouable, bring good technical and economic results for the colliery, and the repairing is successful. 展开更多
关键词 ROADWAY repairing soft ROCK support bolt-shotcrete supporting broken ROCK zone
下载PDF
Mechanical properties and supporting effect of CRLD bolts under static pull test conditions 被引量:10
10
作者 Xiao-ming Sun Yong Zhang +3 位作者 Dong Wang Jun Yang Hui-chen Xu Man-chao He 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第1期1-9,共9页
A device for supporting soft rock masses combined with a constant resistance structure characterized by constant resistance and large deformation at the end of a steel bar, known as the constant resistance and large d... A device for supporting soft rock masses combined with a constant resistance structure characterized by constant resistance and large deformation at the end of a steel bar, known as the constant resistance and large deformation(CRLD) bolt, has recently been developed to counteract soft rock swelling that often occurs during deep mining. In order to further study the mechanical properties of the CRLD bolt, we investigated its mechanical properties by comparison with the conventional strength bolt(rebar) using static pull tests on many aspects, including supporting capacity, elongation, radial deformation, and energy absorption. The tests verified that the mechanical defects of the rebar, which include the decrease of bolt diameter, reduction of supporting capacity, and emergence and evolution of fracture until failure during the whole pull process, were caused by the Poisson's ratio effect. Due to the special structure set on the CRLD bolt, the bolt presents a seemingly unusual phenomenon of the negative Poisson's ratio effect, i.e., the diameter of the constant resistance structure increases while under-pulling. It is the very effect that ensures the extraordinary mechanical properties, including high resistance, large elongation, and strong energy absorption. According to the comparison and analysis of numerical simulation and field test, we can conclude that the CRLD bolt works better than the rebar bolt. 展开更多
关键词 deep mining BOLTS mechanical properties rock support static pull test
下载PDF
Iterative FEA Method for Load Distribution of Flexible Supporting Thin-section Ball Bearing 被引量:2
11
作者 Ju Shu Liqin Wang +1 位作者 Yuze Mao Yuting Ding 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第1期9-14,共6页
To figure out the load distribution of thin-section rolling bearing supported by flexible structure with squirrel cage and the distribution's influence on bearing life,an iterative FEA method is proposed to use th... To figure out the load distribution of thin-section rolling bearing supported by flexible structure with squirrel cage and the distribution's influence on bearing life,an iterative FEA method is proposed to use the result calculated from the Quasi-Dynamic model based on the rigid support hypothesis. The contact angle,contact position and stiffness of equivalent spring are modified during the iterative FEA to optimize the FEA model,and then the bearings' life can be predicted when the error is below 0.5%. It can be concluded that from the analysis results the load distribution under flexible support is more uniform than that of the rigid support,while the maximum load decreases by 11.2% and bearing life increases by 14.7%. The analysis result of different values of thickness of bearing house,rings and hollow shaft demonstrates the thicknesses of bearing house and hollow shaft have a greater influence on the load's uniformity and bearing's life than those of the rings. 展开更多
关键词 FLEXIBLE support with SQUIRREL CAGE ITERATIVE FEA
下载PDF
Cable-truss supporting system for gob-side entry driving in deep mine and its application 被引量:3
12
作者 Yin Qian Jing Hongwen +3 位作者 Dai Dapeng Zhu Tantan Zhao Honghui Meng Bo 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期885-893,共9页
In order to solve the large deformation controlling problem for surrounding rock of gob-side entry driving under common cable anchor support in deep mine, site survey, physical modeling experiment, numerical simulatio... In order to solve the large deformation controlling problem for surrounding rock of gob-side entry driving under common cable anchor support in deep mine, site survey, physical modeling experiment, numerical simulation and field measurement were synthetically used to analyze the deformation and failure characteristics of surrounding rock. Besides, applicability analysis, prestress field distribution characteristics of surrounding rock and the control effect on large deformation of surrounding rock were also further studied for the gob-side entry driving in deep mine using the cable-truss supporting system. The results show that, first, compared with no support and traditional bolt anchor support, roof cable-truss system can effectively restrain the initiation and propagation of tensile cracks in the roof surrounding rock and arc shear cracks in the two sides, moreover, the broken development of surrounding rock, roof separation and extrusion deformation between the two sides of the roadway are all controlled; second, a prestressed belt of trapezoidal shape is generated in the surrounding rock by the cable-truss supporting system, and the prestress field range is wide. Especially, the prestress concentration belt in the shallow surrounding rock can greatly improve the anchoring strength and deformation resisting capability of the rock stratum;third, an optimized support system of ‘‘roof and side anchor net beam, roof cable-truss supporting system and anchor cable of the narrow coal pillar" was put forward, and the support optimization design and field industrial test were conducted for the gob-side entry driving of the working face 5302 in Tangkou Mine, from which a good supporting effect was obtained. 展开更多
关键词 Deep mine Gob-side entry driving Cable-truss supporting system Deformation and failure STABILITY
下载PDF
Application of a combined supporting technology with U-shaped steel support and anchor-grouting to surrounding soft rock reinforcement in roadway 被引量:17
13
作者 王辉 郑朋强 +1 位作者 赵文娟 田洪铭 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第5期1240-1250,共11页
Soft rock surrounding deep roadway has poor stability and long-term rheological effect. More and larger deformation problems of surrounding rock occur due to adverse supporting measures for such roadways, which not on... Soft rock surrounding deep roadway has poor stability and long-term rheological effect. More and larger deformation problems of surrounding rock occur due to adverse supporting measures for such roadways, which not only affects the engineering safety critically but also improves the maintenance costs. This paper takes the main rail roadway with severely deformation in China's Zaoquan coal mine as an example to study the long-term deformation tendency and damage zone by means of in-situ deformation monitoring and acoustic wave testing technique. A three-dimensional finite element model reflecting the engineering geological condition and initial design scheme is established by ABAQUS. Then, on the basis of field monitoring deformation data, the surrounding rock geotechnical and theological parameters of the roadway are obtained by back analysis. A combined supporting technology with U-shaped steel support and anchor-grouting is proposed for the surrounding soft rock. The numerical simulation of the combined supporting technology and in-situ deformation monitoring results show that the soft rock surrounding the roadway has been held effectively. 展开更多
关键词 soft rock roadway rheological effect supporting technology numerical simulation REINFORCEMENT
下载PDF
Upper bound solutions for supporting pressures of shallow tunnels with nonlinear failure criterion 被引量:20
14
作者 YANG Xiao-li ZHANG Dao-bing WANG Zuo-wei 《Journal of Central South University》 SCIE EI CAS 2013年第7期2034-2040,共7页
Linear failure criterion is widely used in calculation of earth pressure acting on shallow tunnels. However, experimental evidence shows that nonlinear failure criterion is able to represent fairly well the failure of... Linear failure criterion is widely used in calculation of earth pressure acting on shallow tunnels. However, experimental evidence shows that nonlinear failure criterion is able to represent fairly well the failure of almost all types of rocks, A nonlinear Hock-Brown failure criterion is employed to estimate the supporting pressures of shallow tunnels in limit analysis framework. Two failure mechanisms are proposed for calculating the work rate of extemal force and the internal energy dissipation. A tangential line to the nonlinear failure criterion is used to formulate the supporting pressure problem as a nonlinear programming problem. The objective function formulated in this way is minimized with respect to the failure mechanism and the location of tangency point. In order to assess the validity, the supporting pressures for the proposed failure mechanisms are calculated and compared with each other, and the present results are compared with previously published solutions when the nonlinear criterion is reduced to linear criterion. The agreement supports the validity of the proposed failure mechanisms. An experiment is conducted to investigate the influences of the nonlinear criterion on collapse shape and supporting pressures of shallow tunnels. 展开更多
关键词 shallow tunnel nonlinear criterion limit analysis supporting pressure failure mechanism
下载PDF
DIAGNOSTICS OF FATIGUE CRACK IN ULTERIOR PLACES OF LARGER-SCALE OVERLOADED SUPPORTING SHAFT BASED ON TIME SERIES AND NEURAL NETWORKS 被引量:2
15
作者 LI Xueiun BIN Guangfu CHU Fulei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第3期79-82,共4页
To improve the diagnosis accuracy and self-adaptability of fatigue crack in ulterior place of the supporting shaft, time series and neural network are attempted to be applied in research on diag-nosing the fatigue cr... To improve the diagnosis accuracy and self-adaptability of fatigue crack in ulterior place of the supporting shaft, time series and neural network are attempted to be applied in research on diag-nosing the fatigue crack’s degree based on analyzing the vibration characteristics of the supporting shaft. By analyzing the characteristic parameter which is easy to be detected from the supporting shaft’s exterior, the time series model parameter which is hypersensitive to the situation of fatigue crack in ulterior place of the supporting shaft is the target input of neural network, and the fatigue crack’s degree value of supporting shaft is the output. The BP network model can be built and net-work can be trained after the structural parameters of network are selected. Furthermore, choosing the other two different group data can test the network. The test result will verify the validity of the BP network model. The result of experiment shows that the method of time series and neural network are effective to diagnose the occurrence and the development of the fatigue crack’s degree in ulterior place of the supporting shaft. 展开更多
关键词 Neural network Time series Larger-scale overloaded supporting shaft Ulterior place Fatigue crack
下载PDF
Dynamic mechanical characteristics and application of constant resistance energy-absorbing supporting material 被引量:12
16
作者 Qi Wang Shuo Xu +3 位作者 Manchao He Bei Jiang Huayong Wei Yue Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第3期447-458,共12页
In deep underground engineering,rock burst and other dynamic disasters are prone to occur due to stress concentration and energy accumulation in surrounding rock.The control of dynamic disasters requires bolts and cab... In deep underground engineering,rock burst and other dynamic disasters are prone to occur due to stress concentration and energy accumulation in surrounding rock.The control of dynamic disasters requires bolts and cables with high strength,high elongation,and high energy-absorbing capacity.Therefore,a constant resistance energy-absorbing(CREA)material is developed.In this study,the dynamic characteristics of the new material are obtained via the drop hammer tests and the Split Hopkinson Pressure Bar(SHPB)tests of the new material and two common bolt(CB)materials widely used in the field.The test results of drop hammer test and SHPB test show that the percentage elongation of CREA material is more than 2.64 and 3.22 times those of the CB material,and the total impact energy acting on CREA material is more than 18.50 and 21.84 times,respectively,indicating that the new material has high elongation and high energy-absorbing capacity.Subsequently,the CREA bolts and cables using the new material are developed,which are applied in roadways with high stress and strong dynamic disturbance.The field monitoring results show that CREA bolts and cables can effectively control the surrounding rock deformation and ensure engineering safety. 展开更多
关键词 Constant resistance energy-absorbing supporting material Dynamic impact tests Mechanical characteristics Field application
下载PDF
Location Service Information Supporting System Based on Ontology 被引量:1
17
作者 HUANG Dong-mei FANG Qian YU Qing-mei 《Journal of Integrative Agriculture》 SCIE CSCD 2012年第5期858-864,共7页
In order to solve the problem of how to collect and manage large amount of location information and improve the accuracy of location service, interactive information supporting system based on ontology and location se... In order to solve the problem of how to collect and manage large amount of location information and improve the accuracy of location service, interactive information supporting system based on ontology and location service is presented in this paper. It can transmit special information about users' location to front-end instantaneously, so it is very convenient for their daily life. It makes full use of the available wireless communication, which is easy to arrange and convenient for users. 展开更多
关键词 ONTOLOGY location service LOCATION information supporting system
下载PDF
Correlation of electromagnetic radiation emitted from coal or rock to supporting resistance 被引量:6
18
作者 JIA Hui-lin WANG En-yuan SONG Xiao-yan ZHANG Hong-jie LI Zhong-hui 《Mining Science and Technology》 EI CAS 2009年第3期317-320,共4页
More accurate forecasting of rock burst might be possible from observations of electromagnetic radiation emitted in the mine.We analyzed experimental observations and field data from the Muchengjian coal mine to study... More accurate forecasting of rock burst might be possible from observations of electromagnetic radiation emitted in the mine.We analyzed experimental observations and field data from the Muchengjian coal mine to study the relationship between electromagnetic radiation signal intensity and stress during the fracturing of coal, or rock, and samples under load.The results show that the signal intensity is positively correlated with stress.In addition, we investigated the change in the electromagnetic radiation intensity, the supporting resistance in a real coal mine environment, and the coal or rock stress in the mining area.The data analysis indicates that:1) electromagnetic radiation intensity can accurately reflect the distribution of stress in the mining area;and, 2) there is a correlation between electromagnetic radiation intensity and supporting resistance.The research has some practical guiding significance for rock burst forecasting and for the prevention of accidents in coal mines. 展开更多
关键词 electromagnetic radiation rock burst supporting resistance coal or rock
下载PDF
Influences of anisotropy and inhomogeneity on supporting pressure of tunnel face with kinematical approach 被引量:3
19
作者 杨小礼 李闻韬 潘秋景 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3536-3543,共8页
Based on the active failure mechanism generated by a spatial discretization technique, the stability of tunnel face was studied. With the help of the spatial discretization technique, not only the anisotropy and inhom... Based on the active failure mechanism generated by a spatial discretization technique, the stability of tunnel face was studied. With the help of the spatial discretization technique, not only the anisotropy and inhomogeneity of the cohesion but also the inhomogeneity of the internal friction angle was taken into account in the analysis of the supporting forces. From the perspective of upper bound theorem, the upper bound solutions of supporting pressure were derived. The influence of the anisotropy and heterogeneity on the supporting forces as well as the failure mechanisms was discussed. The results show that the spatial discretization characteristics of cohesion and internal frictional angle impose a significant effect on the supporting pressure, which indicates that above factors should be considered in the actual engineering. 展开更多
关键词 tunnel face supporting forces ANISOTROPY INHOMOGENEITY upper bound theorem
下载PDF
MECHANICAL ANALYSIS OF CYLINDERS BEING UPSET BETWEEN SPHERICAL CONCAVE PLATEN AND CONCAVE SUPPORTING PLATE 被引量:1
20
作者 LIU Guohui XIAO Wenhui +1 位作者 NI Liyong LIU Zhubai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期99-102,共4页
Mechanical analysis of cylinders being upset between spherical concave platen and concave supporting plate is conducted. Rigid-plastic mechanical models for cylinders are presented. When the ratio of height to diamete... Mechanical analysis of cylinders being upset between spherical concave platen and concave supporting plate is conducted. Rigid-plastic mechanical models for cylinders are presented. When the ratio of height to diameter, is larger than 1, there exists two-dimensional tensile stress in the deformed body, when the ratio is smaller than 1, there exists shear stress in static hydraulic zone. The former breaks through the theory that there is three-dimensional compressive stress irrespective of any ratio of height to diameter. The latter satisfactorily explains the mechanism of layer-like cracks in disk-shaped forgings and the flanges of forged gear axles. The representation of the two models makes the upsetting, theory into correct and perfect stage. 展开更多
关键词 Spherical concave platen Concave supporting plate UPSETTING Tensile stress Shear stress
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部