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论哲学“课堂”
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作者 郑朝晖 《宁波大学学报(教育科学版)》 2009年第5期19-22,共4页
课堂指教师与学生之间的学习关系场,其建立依赖于师生角色的纯粹化、外在环境的虚化与思维的活动化。哲学课堂的成立是一个动态的养成过程,要从哲学能力培养、哲学道场建立与哲学效果评估三个方面进行建构。
关键词 课堂 “道场” 哲学能力
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DISCHARGE CHANNEL GROWTH IN MICRO EDM OF HIGH FREQUENCY PULSE 被引量:2
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作者 刘宇 王津 +1 位作者 王元刚 赵福令 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第4期353-361,共9页
The influences of intense magnetic pinch effect caused by electromagnetic field with high frequency on discharge channel expansion and plasma configuration change are discussed. The change of Lorentz force exerting on... The influences of intense magnetic pinch effect caused by electromagnetic field with high frequency on discharge channel expansion and plasma configuration change are discussed. The change of Lorentz force exerting on charged particles in discharge channel is calculated under the electromagnetic field with high frequency. Through the theoretical analysis and experimental study, the forming process of discharge channel is conjectured. And it is considered that the changes of discharge channel, such as the decrease of diameter and increase of energy density, coming from the intense magnetic pinch effect in high frequency electromagnetic field, are the main reasons for a series of special phenomena on the machined surface in micro EDM. 展开更多
关键词 micro EDM discharge channel high frequency electromagnetic field magnetic pinch effect discharge crater
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“家电下乡”活动的分销渠道建设思考——以湖北省为例 被引量:1
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作者 张辉 《科技资讯》 2009年第13期249-250,共2页
该文在全国开展的"家电下乡"活动的背景下,以湖北省为例,认为农村家电市场消费具有注重经济实用性、消费时间集中、市场分布广、品牌意识逐渐增强等特征,预测了活动持续期间农村家电市场的需求,对目前较成熟的区域代理分销模... 该文在全国开展的"家电下乡"活动的背景下,以湖北省为例,认为农村家电市场消费具有注重经济实用性、消费时间集中、市场分布广、品牌意识逐渐增强等特征,预测了活动持续期间农村家电市场的需求,对目前较成熟的区域代理分销模式、大型连锁终端分销模式、企业自建渠道分销模式、直销模式等四种家电产品分销渠道进行了分析,并给出了针对农村市场的分销渠道创新建议。 展开更多
关键词 家电 农村市场 分销渠道
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Channel Lateral Pocket or Halo Region of NMOSFET Characterized by Interface State R G Current of the Forward Gated Diode
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作者 何进 黄爱华 +1 位作者 张兴 黄如 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第7期826-831,共6页
The channel lateral pocket or halo region of NMOSFET characterized by interface state R G current of a forward gated diode has been investigated numerically for the first time.The result of numerical analysis demons... The channel lateral pocket or halo region of NMOSFET characterized by interface state R G current of a forward gated diode has been investigated numerically for the first time.The result of numerical analysis demonstrates that the effective surface doping concentration and the interface state density of the pocket or halo region are interface states R G current peak position dependent and amplitude dependent,respectively.It can be expressed quantitatively according to the device physics knowledge,thus,the direct characterization of the interface state density and the effective surface doping concentration of the pocket or halo becomes very easy. 展开更多
关键词 forward gated diode R G current MOSFET pocket or halo implant region interface states effective surface doping concentration
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Design for Waterfront Street in Downtown——A Case Study of Honggutan Central Area,Nanchang City
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作者 卢俊 《Agricultural Science & Technology》 CAS 2017年第8期1521-1523,共3页
In the study, waterfront street in Honggutan was researched by field investigation and questionnaire survey from space, transport, scale and human activity. The waterfront street has the following characters: ambiguo... In the study, waterfront street in Honggutan was researched by field investigation and questionnaire survey from space, transport, scale and human activity. The waterfront street has the following characters: ambiguous spatial structure, a lack of spatial design; a lack of business diversity, and over-scaled street space. The scale of waterfront space is amenity, diversified and hydrophilic property. We analyzed and performed a parallel comparison on waterfront street space to help improve Honggutan waterfront street by analyzing its design principles, and taking references from outstanding cases at home and abroad. 展开更多
关键词 Spatial characters of waterfront street Street scale Place attachment Honggutan New District
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《修禅道场碑》与唐代天台宗复兴运动新解
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作者 陆扬 《北京大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第2期85-98,共14页
天台佛教于八九世纪之交出现一场影响深远的复兴运动,在其核心人物荆溪湛然努力下,天台宗再度成为具有高度竞争力的佛教宗派。湛然的复兴努力早为学界所注意,但以他为核心的天台宗门派的诸多细节却仍然较为模糊,其历史信息的保存往往依... 天台佛教于八九世纪之交出现一场影响深远的复兴运动,在其核心人物荆溪湛然努力下,天台宗再度成为具有高度竞争力的佛教宗派。湛然的复兴努力早为学界所注意,但以他为核心的天台宗门派的诸多细节却仍然较为模糊,其历史信息的保存往往依赖于唐宋之际日本求法僧的记录。通过对仅存于天台山的碑铭——梁肃《修禅道场碑》作深入考察,尤其通过发现并释读此碑碑侧与碑阴的重要题刻,可以清楚地看到湛然及其弟子所建立的宗教网络和以佛陇为中心的寺院建设。此研究也有助于重新评估日本佛教文献中有关这段历史的记载的价值,为理解唐后期天台宗的发展以及对日本天台宗的影响提供了新的概观。同时将《修禅道场碑》的立碑放置于9世纪前期的政治文化环境之中,可见这一碑铭的成立过程与唐后期政治变化之间的可能关联。 展开更多
关键词 天台宗 佛陇 天台宗复兴 《修禅道场碑》
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On simulation of precise orbit determination of HY-2 with centimeter precision based on satellite-borne GPS technique 被引量:4
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作者 郭金运 秦建 +1 位作者 孔巧丽 李国伟 《Applied Geophysics》 SCIE CSCD 2012年第1期95-107,117,共14页
The HY-2 satellite carrying a satellite-borne GPS receiver is the first Chinese radar altimeter satellite, whose radial orbit determination precision must reach the centimeter level. Now HY-2 is in the test phase so t... The HY-2 satellite carrying a satellite-borne GPS receiver is the first Chinese radar altimeter satellite, whose radial orbit determination precision must reach the centimeter level. Now HY-2 is in the test phase so that the observations are not openly released. In order to study the precise orbit determination precision and procedure for HY-2 based on the satellite- borne GPS technique, the satellite-borne GPS data are simulated in this paper. The HY-2 satellite-borne GPS antenna can receive at least seven GPS satellites each epoch, which can validate the GPS receiver and antenna design. What's more, the precise orbit determination processing flow is given and precise orbit determination experiments are conducted using the HY-2-borne GPS data with both the reduced-dynamic method and the kinematic geometry method. With the 1 and 3 mm phase data random errors, the radial orbit determination precision can achieve the centimeter level using these two methods and the kinematic orbit accuracy is slightly lower than that of the reduced-dynamic orbit. The earth gravity field model is an important factor which seriously affects the precise orbit determination of altimeter satellites. The reduced-dynamic orbit determination experiments are made with different earth gravity field models, such as EIGEN2, EGM96, TEG4, and GEMT3. Using a large number of high precision satellite-bome GPS data, the HY-2 precise orbit determination can reach the centimeter level with commonly used earth gravity field models up to above 50 degrees and orders. 展开更多
关键词 HY-2 satellite satellite-borne GPS technique precise orbit determination reduced-dynamic method kinematic geometry method
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A 3D-QSAR Study on a Novel Chromanol Class of I_ (Ks) Potassium Channel Blockers
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作者 杜吕佩 李敏勇 +1 位作者 夏霖 尤启冬 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第2期89-94,共6页
Aim and Method A novel three-dimensional quantitative structure-activityrelationship (3D-QSAR) method, self-organizing molecular field analysis (SOMFA) , was used toinvestigate the correlation between the molecular pr... Aim and Method A novel three-dimensional quantitative structure-activityrelationship (3D-QSAR) method, self-organizing molecular field analysis (SOMFA) , was used toinvestigate the correlation between the molecular properties and a class of chromanol analogs asI_(Ks) blockers. Results The cross-validated correlation coefficient q^2 values (0.698) and noncross-validated correlation coefficient r^2 values (0.701) proved a good conventional statisticalcorrelation. Conclusion The final SOMFA model has therefore good predictive activity for the furthermolecular design of chromanol I_(Ks) potassium channel blockers. 展开更多
关键词 quantitative structure-activity relationship self-organizing molecular fieldanalysis I_(Ks) potassium channel blockers chromanol analogs
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Semantic segmentation method of road scene based on Deeplabv3+ and attention mechanism 被引量:6
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作者 BAI Yanqiong ZHENG Yufu TIAN Hong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第4期412-422,共11页
In the study of automatic driving,understanding the road scene is a key to improve driving safety.The semantic segmentation method could divide the image into different areas associated with semantic categories in acc... In the study of automatic driving,understanding the road scene is a key to improve driving safety.The semantic segmentation method could divide the image into different areas associated with semantic categories in accordance with the pixel level,so as to help vehicles to perceive and obtain the surrounding road environment information,which would improve driving safety.Deeplabv3+is the current popular semantic segmentation model.There are phenomena that small targets are missed and similar objects are easily misjudged during its semantic segmentation tasks,which leads to rough segmentation boundary and reduces semantic accuracy.This study focuses on the issue,based on the Deeplabv3+network structure and combined with the attention mechanism,to increase the weight of the segmentation area,and then proposes an improved Deeplabv3+fusion attention mechanism for road scene semantic segmentation method.First,a group of parallel position attention module and channel attention module are introduced on the Deeplabv3+encoding end to capture more spatial context information and high-level semantic information.Then,an attention mechanism is introduced to restore the spatial detail information,and the data shall be normalized in order to accelerate the convergence speed of the model at the decoding end.The effects of model segmentation with different attention-introducing mechanisms are compared and tested on CamVid and Cityscapes datasets.The experimental results show that the mean Intersection over Unons of the improved model segmentation accuracies on the two datasets are boosted by 6.88%and 2.58%,respectively,which is better than using Deeplabv3+.This method does not significantly increase the amount of network calculation and complexity,and has a good balance of speed and accuracy. 展开更多
关键词 autonomous driving road scene semantic segmentation Deeplabv3+ attention mechanism
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Support pressure assessment for deep buried railway tunnels using BQ-index 被引量:6
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作者 WANG Ming-nian WANG Zhi-long +3 位作者 TONG Jian-jun ZHANG Xiao DONG Yu-cang LIU Da-gang 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第1期247-263,共17页
Estimation of support pressure is extremely important to the support system design and the construction safety of tunnels.At present,there are many methods for the estimation of support pressure based on different roc... Estimation of support pressure is extremely important to the support system design and the construction safety of tunnels.At present,there are many methods for the estimation of support pressure based on different rock mass classification systems,such as Q system,GSI system and RMR system.However,various rock mass classification systems are based on different tunnel geologic conditions in various regions.Therefore,each rock mass classification system has a certain regionality.In China,the BQ-Inex(BQ system)has been widely used in the field of rock engineering ever since its development.Unfortunately,there is still no estimation method of support pressure with BQ-index as parameters.Based on the field test data from 54 tunnels in China,a new empirical method considering BQ-Inex,tunnel span and rock weight is proposed to estimate the support pressure using multiple nonlinear regression analysis methods.And then the significance and necessity of support pressure estimation method for the safety of tunnel construction in China is explained through the comparison and analysis with the existing internationally widely used support pressure estimation methods of RMR system,Q system and GSI system.Finally,the empirical method of estimating the support pressure based on BQ-index was applied to designing the support system in the China’s high-speed railway tunnel—Zhengwan high-speed railway and the rationality of this method has been verified through the data of field test. 展开更多
关键词 rock mass classification support pressure deep buried tunnel field test multiple nonlinear regression analysis BQ-Index
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A novel localization method for noninvasive monitoring capsule 被引量:3
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作者 何文辉 Yan Guozheng Jiang Pingping Cuo Xudong 《High Technology Letters》 EI CAS 2006年第3期255-259,共5页
Noninvasive monitoring capsule for gastrointestinal tract can De swauowed by patient.It is of great importance for the physician to monitor the precise position of capsule in gastrointestinal tract. The authors invest... Noninvasive monitoring capsule for gastrointestinal tract can De swauowed by patient.It is of great importance for the physician to monitor the precise position of capsule in gastrointestinal tract. The authors investigated a novel method for it. Using three coils with DC current to excite magnetic field and one triaxial magnetoresistive sensor to measure the excited magnetic vectors, they tried to solve the problem. The authors provided the localization principle of the method and analyzed it by an experiment, too. The method may be applied in practice in the future though it is still immature now. 展开更多
关键词 gastrointestinal tract COIL magnetic field LOCALIZATION
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A method for computing unsupported roof distance in roadway advancement and its in-situ application 被引量:2
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作者 Chen Yong Bai Jianbiao +2 位作者 Yan Shuai Hao Shengpeng Dao Viet Doan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期551-556,共6页
A reasonable unsupported roof distance(URD) when advancing underground coal mine roadways can contribute greatly to safe and rapid roadway development.A mechanical model of the roof,using the relationship between the ... A reasonable unsupported roof distance(URD) when advancing underground coal mine roadways can contribute greatly to safe and rapid roadway development.A mechanical model of the roof,using the relationship between the roof stress distribution and URD,obtained by the difference method,and roof stability according to the in-situ roof stress and rock mass strength was developed.We subsequently designed a proper range of URD,developed a testing method of URD with the function of mining protection,evaluated roof stability through analyzing the test data and then determined a reasonable URD.Considering the factors of the geological conditions,the immediate roof stability and the efficiency of the labor arrangement system,the URD of the advancing roadway of 9802 working face in Zhangshuanglou coal mine was determined to be 6 m using the proposed method.The results show that,when a 2 m length of roadway was reinforced by temporary support and high pre-stressed bolt support after the roadway advancement of 6 m per cycle,the speed and the security of the roadway development can be achieved and the advance rate can reach more than 400 m per month. 展开更多
关键词 Unsupported roof distance (URD)Roadway advancement Difference method Roof stress Drivage per cycle Unsupported roof distance test
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Extraction of amplitude-preserving angle gathers based on vector wavefield reverse-time migration 被引量:1
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作者 Yang Jia-Jia Luan Xi-Wu +4 位作者 He Bing-Shou Fang Gang Pan Jun Ran Wei-Min Jiang Tao 《Applied Geophysics》 SCIE CSCD 2017年第4期492-504,620,共14页
Angle-domain common-image gathers (ADCIGs) transformed from the shot- domain common-offset gathers are input to migration velocity analysis (MVA) and prestack inversion. ADCIGs are non-illusion prestack inversion ... Angle-domain common-image gathers (ADCIGs) transformed from the shot- domain common-offset gathers are input to migration velocity analysis (MVA) and prestack inversion. ADCIGs are non-illusion prestack inversion gathers, and thus, accurate. We studied the extraction of elastic-wave ADCIGs based on amplitude-preserving elastic-wave reverse- time migration for calculating the incidence angle of P- and S-waves at each image point and for different source locations. The P- and S-waves share the same incident angle, namely the incident angle of the source P-waves. The angle of incidence of the source P-wavefield was the difference between the source P-wave propagation angle and the reflector dips. The propagation angle of the source P-waves was obtained from the polarization vector of the decomposed P-waves. The reflectors' normal direction angle was obtained using the complex wavenumber of the stacked reverse-time migration (RTM) images. The ADCIGs of P- and S-waves were obtained by rearranging the common-shot migration gathers based on the incident angle. We used a horizontally layered model, the graben medium model, and part of the Marmousi-II elastic model and field data to test the proposed algorithm. The results suggested that the proposed method can efficiently extract the P- and S-wave ADCIGs of the elastic-wave reverse-time migration, the P- and S-wave incident angle, and the angle-gather amplitude fidelity, and improve the MVA and prestack inversion. 展开更多
关键词 Elastic wave reverse-time migration vector wavefield angle-domain common- image gathers amplitude-preserving migration
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Research on the sales channels of the household appliances market 被引量:1
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作者 SUN Jian-xia 《Chinese Business Review》 2007年第3期28-33,共6页
Chinese traditional sales channels are seriously attacked by the new ones. Household appliances industry will realize the specialized divisions of. development, manufacture, sale and services completely. The model of ... Chinese traditional sales channels are seriously attacked by the new ones. Household appliances industry will realize the specialized divisions of. development, manufacture, sale and services completely. The model of sales channel in marketing is set as the core of this research; the merits and demerits of different sales channels are analyzed; the complicated selective relationship and the conflicts among the manufacturer, middlemen, and ultimate consumers, and the solutions to present multi-channels market and the developments of the sales channels are elaborated in an overall view; the opinion that the only way to develop this industry is raised to establish the competitive sales channels. The aim is to let local household appliances industry use the natural merits to build up a suitable channel rapidly and efficiently, and to speed up the self development and oeffection. 展开更多
关键词 household appliances industry sales channels channels building
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Numerical simulation study on the influence of the ground stress field on the stability of roadways 被引量:8
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作者 ZHANG Hualei 《Mining Science and Technology》 EI CAS 2010年第5期707-711,共5页
We adopt the concept of generalized plane strain to model a roadway in a stress field.This can avoid limitations caused by simplifying the stress analysis as plane strain.FLAC3D was used to investigate the maximum ten... We adopt the concept of generalized plane strain to model a roadway in a stress field.This can avoid limitations caused by simplifying the stress analysis as plane strain.FLAC3D was used to investigate the maximum tensile stress and displacement of a roadway in a known stress field for angles,α,between the roadway axial direction and the maximum principal stress of 0°,30°,45°,60° and 90°.This theory was applied to the analysis of an engineering case.The results indicate that stress and displacement of the surrounding rock increase as the angle,α,increases.This provides some significant guidance for a reasonable layout of roadways in a known stress field. 展开更多
关键词 ROADWAY ground stress field generalized plane strain numerical simulation
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Characteristics of Transient Outward Potassium Channel Exposed to 3 mT Static Magnetic Field 被引量:1
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作者 李刚 程立君 +3 位作者 乔晓艳 林凌 张璐 李媛媛 《Transactions of Tianjin University》 EI CAS 2009年第5期319-323,共5页
Acutely isolated mouse hippocampal CA3 pyramidal neurons were exposed to 3 mT static magnetic field,and the characteristics of transient outward K+ channel were studied using the whole-cell patch-clamp technique.The e... Acutely isolated mouse hippocampal CA3 pyramidal neurons were exposed to 3 mT static magnetic field,and the characteristics of transient outward K+ channel were studied using the whole-cell patch-clamp technique.The experiment revealed that the amplitude of transient outward potassium channel current was reduced.The maximum activated current densities of control group and exposure group were 163.62±20.68 pA/pF and 98.74±16.57 pA/pF(n=12,P<0.01) respectively.The static magnetic field exposure affected the activation and inactivation process of transient outward potassium channel current.Due to the magnetic field exposure,the half-activation voltage of the activation curves changed from 5.59±1.96 mV to 27.87±7.24 mV(n=12,P<0.05) ,and the slope factor changed from 19.43±2.11 mV to 25.87±4.22 mV(n=12,P<0.05) .The half-inactivation voltage of the inactivation curves also changed from-56.09±0.89 mV to-57.16±1.10 mV(n=12,P>0.05) and the slope factor of the inactivation curves from 8.69±0.80 mV to 10.87±1.02 mV(n=12,P<0.05) .The results show that the static magnetic field can change the characteristics of transient outward K+ channel,and affect the physiological functions of neurons. 展开更多
关键词 transient outward potassium channel current patch-clamp technique static magnetic field biological effect NEURONS
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Velocity Field and Variation of Wall Thickness During Tube Dieless Upsetting 被引量:1
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作者 王忠堂 栾瑰馥 张士宏 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第2期218-222,共5页
Theoretical analyses show that the variation of wall thickness is in direct proportion to outer-diameter, inter-diameter, and (1+R_s)^(1/2) (Rs is sectional increase ratio of tube), the theoretical calculated results ... Theoretical analyses show that the variation of wall thickness is in direct proportion to outer-diameter, inter-diameter, and (1+R_s)^(1/2) (Rs is sectional increase ratio of tube), the theoretical calculated results of wall thickness during tube dieless upsetting are very approximate to the experimental one. As the width of deformation field increases, both the variation of wall thickness and the derivative of wall thickness variation to width of deformation field (to/tf) reduce. 展开更多
关键词 dieless upsetting TUBE wall thickness velocity field
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Similarity simulation of bolt support in a coal roadway in a tectonic stress field 被引量:6
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作者 LU Yan LIU Changyou 《Mining Science and Technology》 EI CAS 2010年第5期718-722,共5页
In order to study the mechanism of bolt support and the behavior of strata in a coal roadway under tectonic stress,deformation and destruction of a roof,floor and sides were studied using an experiment in similarity s... In order to study the mechanism of bolt support and the behavior of strata in a coal roadway under tectonic stress,deformation and destruction of a roof,floor and sides were studied using an experiment in similarity simulation.We also studied the mechanism and types of bolt support functions in the coal roadway.The results show that with an increase in horizontal tectonic stress,the strata in the roof and floor of the roadway gradually separate and become shear failure areas.Coal in side walls moves,but its integrity remains intact.Side bolts are mainly affected by tension and roof bolts by the effect of shear. 展开更多
关键词 tectonic stress coal roadway bolt support similarity simulation
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Study on visualization simulation of temperature distributions in surrounding rock of tunnels in a deep mine 被引量:1
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作者 孙培德 《Journal of Coal Science & Engineering(China)》 2006年第2期57-61,共5页
Based on the mathematical model for rock temperature distribution in a geo-thermal field,the properties of rock temperature distribution in geothermal field for fourkinds of surrounding rock cross-sections of tunnels ... Based on the mathematical model for rock temperature distribution in a geo-thermal field,the properties of rock temperature distribution in geothermal field for fourkinds of surrounding rock cross-sections of tunnels in a deep mine were simulated by us-ing finite element method.It is shown that the relationship for rock temperature distributionvaried with the geothermal parameters,time and space.Namely, 2-dimensionaltime-dependent isograms clearly showed the process for rock temperature variation anddistribution in a geothermal field which has been redisplayed with visualization numericalsimulation. 展开更多
关键词 deep mine geothermal field temperature distribution visualization simulation finite element method
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Unsteady temperature field of surrounding rock mass in high geothermal roadway during mechanical ventilation 被引量:2
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作者 张源 万志军 +2 位作者 顾斌 周长冰 程敬义 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期374-381,共8页
To explore the spatial-temporal evolution law of rock mass temperature in high geothermal roadway during mechar^ical ventilation, a series of experiments were conducted based on the physical simulation test system of ... To explore the spatial-temporal evolution law of rock mass temperature in high geothermal roadway during mechar^ical ventilation, a series of experiments were conducted based on the physical simulation test system of thermal and humid environment in high geothermal roadway, which is a method independently developed by China University of Mining and Technology. The results indicate that during ventilation, the disturbed region of the temperature extends gradually from shallow area to deep area in the surrounding rock mass of the roadway. Meanwhile, the temperature increases as the exponential function from shallow area to deep, with steady decrease of the temperature gradient and heat flux. As the ventilation proceeds, the relationship between dimensionless temperature and dimensionless time approximately meets Hill function. 展开更多
关键词 high geothermal mine heat hazard unsteady temperature field evolution law mechanical ventilation
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