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Excited response of granular ores in vibrating field

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Journal of Central South University of Technology 2001年第2期8卷 120-124页

作者： LI Jian hua 1,2., SUN Ye zhi 1, WU Ai xiang 1, CHEN Shou ru 1 (1.college of resources, Environment and {2. Engineering, Central South University, Changsha 410083.{3. 2.The 5th Building Company in Guangdong Province, Shaoguan 512.2., C 1. college of resources Environment and Civil Engineering Central South University 410083 Changsha China 2. The 5th Building Company in Guangdong Province 512026 Shaoguan China

The dynamical theory was utilized to probe into the law of the excited response of granular ores generated by the exciting action of exciter and the influence of wave propagation in vibrating field. The exciter with double axes was presented as an example, and the principle of exciter and its mathematical expression of the excitation force were given. The granular ores have viscidity and damping speciality, on the basis of which the motion equation of excited response of ores was established and the approximate expression of mode displacement by harmonic excitation and the steady effect solution of coordinate response were deduced. Utilizing the step by step integration method, the recursion relation matrix of displacement, velocity and acceleration of the excited response of ores were obtained, and the computational flow chart and a computational example were given. The results show that the excited response can change the dynamical character and the flowing characteristic of granular ores.

关键词： excitation system excited response granular ore step by step integration method

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Evaluation on Filter Cleaning Performances Measured by VDI and JIS Testing Rigs for Cleanable Fabric Filter

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Evaluation on Filter Cleaning Performances Measured by VDI a...

2.06（沈阳）国际安全科学与技术学术研讨会

作者： MAO Ning CHEN Baozhi college of Resource and civil Engineering {2. University {3. 110004 china

＜正＞VDI type - 1 rig and JIS rig are the two major testing rigs for cleanable fabric filters. We measured the filter cleaning performance using these rigs and the results were compared in order to characterize the two testing methods. It is found that filter cleaning has no direct relation with flow type of test rig. And configuration differences between VDI type -1 and JIS rigs causes the various differential pressure development curves in which VDI type - 1 rig shows a little higher cake release effect than JIS rig. Moreover, a new concept of impulse per unit area is introduced for the evaluation on filter cleaning performance in a quantitative way.

关键词： VDI type - 1 rig JIS rig flow type differential pressure acceleration

Robust and Rapid Control for ABS Based on Global Sliding Mode

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Robust and Rapid Control for ABS Based on Global Sliding Mod...

第2.届中国控制与决策会议

作者： Xu Ping 1 , Li Wei 2.Zheng Yan 3.1. Aeronautical Automation college, {2. Aviation University of china, Tianjin 3.03.0, china2.china Mobile Communications Corporation HeBei TangShan Brance, Tangshan 063.04, china3. Information Science and Engineering, northeastern University, {12. 110004, china

To satisfy the stability and anti-jamming performance, robust theory must be adopted in the design for Antilock Braking System （ABS） controller. In this paper, the nonlinear and time-varying mathematical model of the antilock braking system （ABS） is established, the global sliding mode controller is designed based on slip-ratio, which make the system State always lies on the sliding surface, and the robustness of sliding mode control system can be improved to some extent. The Simulation results on different surfaces prove that this strategy is feasible and effective, which can shorten the braking distance and the braking time.

关键词： Antilock Braking System (ABS) global sliding mode sliding surface disturbances robustness

Effect of Different Irrigation Methods on Dissolved Organic Carbon and Microbial Biomass Carbon in the Greenhouse Soil

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Agricultural Sciences in china 2010年第8期9卷 1175-1182页

作者： HAN Lin,ZHANG Yu-long,JIN Shuo,WANG Jiao,WEI Yan-yan,CUI Ning and WEI Wei college of Land and Environmental Sciences,shenyang Agricultural University/Liaoning Key Laboratory of Agricultural {2. and Environment,shenyang 110161,P.R.china [a] college of Land and Environmental Sciences Shenyang Agricultural University/Liaoning Key Laboratory of Agricultural Resources and Environment Shenyang 110161 P.R.China

The objective of this study was to investigate the contents and distribution of dissolved organic carbon （DOC） and microbial biomass carbon （MBC） at 0-100 cm soil depth under three irrigation treatments, viz., subsurface, drip and furrow irrigation in the greenhouse soil. The soil samples were collected at different depths （0-100 cm）, and the contents of soil total organic carbon （TOC）, DOC and MBC were analysed. The experiment was conducted for 10 yr, during which period the application of fertilizers and crop management practices were kept identical. The results showed that the contents of TOC, DOC and MBC were significantly affected by different irrigation regimes, decreased with the increase of soil depth. TOC at 0-10 and 80-100 cm soil depths followed the order of furrow irrigation 〉 subsurface irrigation 〉 drip irrigation, whereas at the depth of 10-80 cm followed the order of subsurface irrigation 〉 furrow irrigation 〉 drip irrigation. DOC and MBC contents at 0-100 cm soil depths followed the order of furrow irrigation 〉 drip irrigation 〉 subsurface irrigation, and drip irrigation 〉 furrow irrigation 〉 subsurface irrigation, respectively. The ratios of DOC and MBC to TOC accounted for 4.98-12.87% and 1.48-2.82., respectively, which were the highest in the drip irrigation treatment, followed were in the furrow irrigation treatment, and the lowest in subsurface irrigation treatment. There were significant positive correlations among the contents of DOC, MBC and TOC in all irrigation treatments. The furrow irrigation facilitated the accumulation of TOC and DOC, while drip irrigation increased the MBC. The content of TOC and the ratios of DOC to TOC were the lowest in subsurface irrigation treatment.

关键词： greenhouse irrigation methods total organic carbon dissolved organic carbon microbial biomass carbon

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Time-dependent Power Spectral Density Estimation of AE signals of Rock Based on Wavelet Transform

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Time-dependent Power Spectral Density Estimation of AE signa...

2.11 Chinese Control and Decision Conference（CCDC）

作者： KANG Yumei1,ZHU Wancheng1,BAI Quan2.WU JinLin1 1(college of resources and {2. Engineering,{3. University,shenyang,Liaoning 110004,china2.School of Architecture and {2. Engineering,shenyang University of Technology,shenyang,Liaoning 110870 china)

Understanding and cognition on characteristics of acoustic emission （AE） signals is the foundation and precondition of read comprehensively AE *** Fourier amplitude spectrum and power spectral density（PSD） representations based on Fourier transform have limitations,that is,it loses any information related to time and is unable to completely reflect the non-stationary characteristics of AE signals *** this paper,based on wavelet transform,the relationship between wavelet coefficient in every frequency bands and power spectral density is derived;PSD estimate method and time-dependent PSD estimate method based on wavelet transform are also presented in this *** feasibility of the presented method is illustrated by AE Signal of rock processing and analysis.

关键词： acoustic emission (AE) signals wavelet transform time-dependent power spectral density (PSD) non-stationary process

不同层状结构岩体中隧洞开挖诱发岩爆机理研究

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沈阳建筑大学学报(自然科学版) 2011年第3期27卷 442-450页

作者：黄志平赵文唐春安朱万成张滨州东北大学资源与土木工程学院沈阳建筑大学土木工程学院大连理工大学建设工程学部金诚信矿业建设集团有限公司

目的研究不同层状岩体渐进破裂直至岩爆临界状态前的孕育过程及其微破裂前兆规律.方法在完整岩体、水平层状岩体、及急倾斜层状岩体中建立隧洞开挖三个数值模型,运用RFPA2.对隧洞开挖诱发岩爆机理进行数值试验研究.结果 RFPA2.模拟隧洞... 详细信息

目的研究不同层状岩体渐进破裂直至岩爆临界状态前的孕育过程及其微破裂前兆规律.方法在完整岩体、水平层状岩体、及急倾斜层状岩体中建立隧洞开挖三个数值模型,运用RFPA2.对隧洞开挖诱发岩爆机理进行数值试验研究.结果 RFPA2.模拟隧洞卸载失稳是可行的,同时表明结构面对隧洞围岩的破坏失稳模式有显著影响,不同性质的结构面使得隧洞最后破坏状态完全不一样.结论隧洞开挖卸载岩爆破坏程度在水平层状岩体中表现最为强烈,倾斜层状岩体中次之,完整岩体中相对最弱.隧洞破坏在水平层状岩体与完整岩体中具有对称性,倾斜层状岩体中具有明显的非对称特征.围岩卸荷破坏具有明显的脆性特征,岩体破坏时表现出沿卸荷方向强烈扩容破坏特征,洞周围岩产生明显的侧向膨胀,致使洞室断面缩小.

关键词：数值模拟层状岩体诱发岩爆隧洞开挖

Studying the Lithology Identification Method from Well logs Based on DE-SVM

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Studying the Lithology Identification Method from Well logs ...

2.09中国控制与决策会议

作者： Jiang An-nan~1,Jin Lu~2.1.Traffic and Logistics college,Dalian Maritime University,Dalian 11602.,china 2.Resource and {2. Engineering college of northeastern,shenyang,110004,china

＜正＞Identify the rock lithology has important meaning for estimating the reserve of petroleum,adopting proper drilling technology and improving *** lithology identification from well log based on DE-SVM was proposed and *** digitization and collection the data of the well logs and cores observation results,the mapping model between well logs and strata lithology is established by Support vector machine（SVM）,so the strata lithology of wells without rock cores can be automatically gotten by well *** the penal factor c and kernel parameterσaffect the identification accuracy evidently,the global optimization arithmetic- difference evolutionary（DE） is coupled with SVM to optimize above parameters in order to improve the performance of SVM *** model theory and algorithm are discussed as well as the true example is calculated,it is stated that the proposed method is feasible and can get satisfied results.

关键词： Lithology Identification Well Logging Support Vector Machine Difference Evolutionary

Research on Hybrid of ESP-baghouse Dust Collector

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Research on Hybrid of ESP-baghouse Dust Collector

2.06（沈阳）国际安全科学与技术学术研讨会

作者： LIU Jingxian ZHENG Shuangyang SUN Xi college of Resource & civil Engineering {2. University {3. 110004 china

＜正＞ESP and baghouse are the main industrial equipment to remove dust. Integrated ESP and baghouse in one device can take their advantages. Large particles have been captured by ESP and fine particle colleted by baghouse. Some experiments have been done to study the particle size distribution efficiency, pressure drop, relationship between efficiency and velocity. Experiment reswlts shows that the hybrid have a better performance than ESP and baghouse, will be a competitor in the future.

关键词： ESP bughouse hybrid dust collector smoke

Applying Acoustic Emission Technique in Rock Mechanics

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Applying Acoustic Emission Technique in Rock Mechanics

第二届全国压电和声波理论及器件技术研讨会

作者： Xingdong Zhao,Yuanhui Li (School of resources & civil Engineering,{2. University,{3.,110006,P.R.china)

Acoustic emission(AE),which is produced by the micro-cracks occurrence or growth,is an ubiguitous phenomenon associated with brittle fracture in many materials,such as *** technique can monitor the microfractures development in the rock sample continuously and in-real-time,which is better than other methods.A Simplex and Geiger location algorithm allows AE event location from first arrival times to be determined by AE sensors,which was applied to study the crack initiation and propagation process,also to analyze the crack spatial evolution mode with stress changing during the total loading *** this paper,introducing AE location method and reverse evolvation principle;applying different location algorithm to study AE location event in different rock;analyzing the location error of AE *** on above study,experimental study AE location event of signal crack,double cracks and normal rock sample,and study AE space evolvement mode of crack initiation,crack propagation and coalescence during rock failure process;analyzing relation to stress(strain),loading time and AE events,which is contributed to study failure character of rock instability process;by AE experiment,analyzing inner and outer factor influence AE event location;By AE event location technique, studying systematically different rock samples(granite,red granite,marble,black marble and sandstone), loading mode(uniaxial loading,cyclic loading and three point bending loading),loading route,Brazil splitting testing and size effect *** analyzing the relation to AE activity and rock failure process, disclosuring inner relation to AE activity and rock failure and instability,which is very significant to study the mechanism of rock failure.

关键词： Acoustic emission Rock failure Uniaxial loading Crack propagation process