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Stability monitoring and evaluation of the modeled test square for prehistoric earthen sites during excavation period 被引量:3
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作者 谌文武 戴鹏飞 +3 位作者 张景科 陈鹏飞 郭青林 孙满利 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期464-471,共8页
In order to explore the stability of test square during archaeological excavation for prehistoric earthen sites in Hangzhou, a modeled test square with 2. 3 min depth, inplane dimensions of 5 min width by 5 m in lengt... In order to explore the stability of test square during archaeological excavation for prehistoric earthen sites in Hangzhou, a modeled test square with 2. 3 min depth, inplane dimensions of 5 min width by 5 m in length, and an archaeological column in the middle was excavated by means of a top-down excavation technique. To investigate the stability performance of the modeled test square and the associated effect on the adjacent area, a real-time comprehensive instrumentation program was conducted during the excavation. Field observations included ground settlements, lateral displacement, pore pressure and underground water level. Monitoring data indicates that the ground settlement induced by dewatering and unloading action basically decreases with the increase of the distance away from the pit edge, and the lateral displacements at four sides showa nonlinear variation along the depth. The maximum value is far below the acceptable value regulated by the related standard,which validates the stability of the modeled test square during excavation. Variations of pore pressure and water level suggest that long-term stability should be paid more attention due to the slowconsolidation of soft soil. Meanwhile, it is proved that the step shape of the wall can resist lateral displacement more effectively than the vertical shape of wall. This case study provides insights into the real archaeological excavation in Hangzhou, in particular Liangzhu prehistoric earthen sites. 展开更多
关键词 prehistoric earthen sites archaeological excavation test square stability monitoring
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Stability of finite difference numerical simulations of acoustic logging-while-drilling with different perfectly matched layer schemes 被引量:2
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作者 王华 陶果 +2 位作者 尚学峰 方鑫定 Daniel R Burns 《Applied Geophysics》 SCIE CSCD 2013年第4期384-396,510,511,共15页
In acoustic logging-while-drilling (ALWD) finite difference in time domain (FDTD) simulations, large drill collar occupies, most of the fluid-filled borehole and divides the borehole fluid into two thin fluid colu... In acoustic logging-while-drilling (ALWD) finite difference in time domain (FDTD) simulations, large drill collar occupies, most of the fluid-filled borehole and divides the borehole fluid into two thin fluid columns (radius -27 mm). Fine grids and large computational models are required to model the thin fluid region between the tool and the formation. As a result, small time step and more iterations are needed, which increases the cumulative numerical error. Furthermore, due to high impedance contrast between the drill collar and fluid in the borehole (the difference is 〉30 times), the stability and efficiency of the perfectly matched layer (PML) scheme is critical to simulate complicated wave modes accurately. In this paper, we compared four different PML implementations in a staggered grid finite difference in time domain (FDTD) in the ALWD simulation, including field-splitting PML (SPML), multiaxial PML(M- PML), non-splitting PML (NPML), and complex frequency-shifted PML (CFS-PML). The comparison indicated that NPML and CFS-PML can absorb the guided wave reflection from the computational boundaries more efficiently than SPML and M-PML. For large simulation time, SPML, M-PML, and NPML are numerically unstable. However, the stability of M-PML can be improved further to some extent. Based on the analysis, we proposed that the CFS-PML method is used in FDTD to eliminate the numerical instability and to improve the efficiency of absorption in the PML layers for LWD modeling. The optimal values of CFS-PML parameters in the LWD simulation were investigated based on thousands of 3D simulations. For typical LWD cases, the best maximum value of the quadratic damping profile was obtained using one do. The optimal parameter space for the maximum value of the linear frequency-shifted factor (a0) and the scaling factor (β0) depended on the thickness of the PML layer. For typical formations, if the PML thickness is 10 grid points, the global error can be reduced to 〈1% using the optimal PML parameters, and the error will decrease as the PML thickness increases. 展开更多
关键词 PML schemes FD simulation LWD acoustic
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新西兰原木装运和绑扎注意事项
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作者 孙立 《航海》 2019年第6期53-56,共4页
木材船装载涉及的安全技术面较广,为保障积载的航次安全,通常需要船舶在货物装船前做好相应准备,特别是预配载、GM计算、宣载、安全绑扎等方面,保证货物的安全装运、保管和交付。
关键词 木材货物的积载 稳性测定 装卸保管 人身安全
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A novel closed-loop vacuum silicon microgyroscope
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作者 夏敦柱 王寿荣 周百令 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期63-67,共5页
A novel closed-loop control strategy of a silicon microgyroscope (SMG) is proposed. The SMG is sealed in metal can package in drive and sense modes and works under the air pressure of 10 Pa. Its quality factor reach... A novel closed-loop control strategy of a silicon microgyroscope (SMG) is proposed. The SMG is sealed in metal can package in drive and sense modes and works under the air pressure of 10 Pa. Its quality factor reaches greater than l0 000. Self-oscillating and closed-loop methods based on electrostatic force feedback are adopted in both measure and control circuits. Both single side driving and sensing methods are used to simplify the drive circuit. These dual channel decomposition and reconstruction closed loops are applied in sense modes. The testing results demonstrate that useful signals and guadrature signals do not interact with each other because of the decoupling of their phases. Under the condition of a scale factor of 9. 6 mV/((°) .s), in a full measurement range of±300 (°)/s, the zero bias stability reaches 28 (°)/h with a nonlinear coefficient of 400 × 10^-6 and a simulated bandwidth of more than 100 Hz. The overall performance is improved by two orders of magnitude in comparison to that at atmospheric pressure. 展开更多
关键词 silicon micro-gyroscope (SMG) self oscillating dual-channel closed-loop detection scale factor zero bias stability
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Simplified microsatellite instability detection protocol provides equivalent sensitivity to robust detection strategies in Lynch syndrome patients 被引量:4
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作者 Hadi Babaei Mehrdad Zeinalian +3 位作者 Mohammad Hassan Emami Mortaza Hashemzadeh Najmeh Farahani Rasoul Salehi 《Cancer Biology & Medicine》 SCIE CAS CSCD 2017年第2期142-150,共9页
Objective:Germline mutations in mismatch repair(MMR)genes cause Lynch syndrome(LS).LS is an inherited disease,and an important consequence of MMR deficiency is microsatellite instability(MSI)phenotype.MSI phenotype in... Objective:Germline mutations in mismatch repair(MMR)genes cause Lynch syndrome(LS).LS is an inherited disease,and an important consequence of MMR deficiency is microsatellite instability(MSI)phenotype.MSI phenotype influences the efficacy of5 fluorouracil(5-FU)chemotherapy.Reproducible,cost effective,and easy to perform laboratory tests are required to include MSI detection in routine laboratory practice.Evaluation of CAT25 as monomorphic short tandem repeat sequence enables CAT25 to be an efficient screening tool among hereditary nonpolyposis colorectal cancer(HNPCC)patients compared with other methods used currently.Methods:Based on Amsterdam II criteria,31 patients in 31 families were shortlisted from a total number of 1,659 colorectal cancer patients.MSI status was examined in these patients using CAT25 and a commercially available Promega MSI five-markerbased detection system as well as immunohistochemical(IHC)staining of four important MMR proteins.Patients were scored as high microsatellite instable(MSI-H),low(MSI-L),or stable(MSS).MSI status determined by CAT25 single mononucleotide marker was compared with that of five mononucleotide markers,Promega commercial kit,and IHC method.Results:MMR protein deficiency was observed on 7/31 probands using IHC methodology and 6/31 categorized as MSI-H using commercial kit or CAT25 single marker.The sensitivity and specificity of the CAT25 single marker were the same as those detected by five-marker Promega commercial kit in our patients.Conclusions:Based on our results,the performance of the CAT25 single mononucleotide marker for MSI status determination in our HNPCC patients is the same as that of the five-marker-based commercial kit. 展开更多
关键词 Lynch syndrome HNPCC DNA mismatch repair IHC microsatellite instability
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Robustly stable model predictive control based on parallel support vector machines with linear kernel 被引量:4
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作者 包哲静 钟伟民 +1 位作者 皮道映 孙优贤 《Journal of Central South University of Technology》 EI 2007年第5期701-707,共7页
Robustly stable multi-step-ahead model predictive control (MPC) based on parallel support vector machines (SVMs) with linear kernel was proposed. First, an analytical solution of optimal control laws of parallel SVMs ... Robustly stable multi-step-ahead model predictive control (MPC) based on parallel support vector machines (SVMs) with linear kernel was proposed. First, an analytical solution of optimal control laws of parallel SVMs based MPC was derived, and then the necessary and sufficient stability condition for MPC closed loop was given according to SVM model, and finally a method of judging the discrepancy between SVM model and the actual plant was presented, and consequently the constraint sets, which can guarantee that the stability condition is still robust for model/plant mismatch within some given bounds, were obtained by applying small-gain theorem. Simulation experiments show the proposed stability condition and robust constraint sets can provide a convenient way of adjusting controller parameters to ensure a closed-loop with larger stable margin. 展开更多
关键词 parallel support vector machines model predictive control stability ROBUSTNESS
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Energy expenditure and muscular activation patterns through active sitting on compliant surfaces 被引量:1
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作者 D.Clark Dickin Rachel K.Surowiec Henry Wang 《Journal of Sport and Health Science》 SCIE 2017年第2期207-212,共6页
Purpose: To test the effectiveness of sitting surfaces with varied amounts of stability on muscle activity and energy expenditure.Methods: Using a within-participants repeated measures design, 11 healthy young-adult f... Purpose: To test the effectiveness of sitting surfaces with varied amounts of stability on muscle activity and energy expenditure.Methods: Using a within-participants repeated measures design, 11 healthy young-adult females(age = 20.0 ± 1.8 years) were measured using indirect calorimetry to assess energy expenditure, and electromyography to assess muscular activation in trunk and leg musculature under 3different sitting surfaces: flat-firm surface, air-filled cushion, and a stability ball. Data were analyzed using repeated measures analysis of variance with follow-up pairwise contrasts used to determine the specific effects of sitting surface on muscle activation and energy expenditure.Results: Significantly greater energy expenditure was recorded for the stability ball(p = 0.01) and the cushion(p = 0.03) over the flat surface(10.4% and 9.6% greater, respectively), with no differences between the ball and the cushion. Both the ball and the cushion produced higher tibialis anterior activation over the flat surface(1.09 and 0.63 root-mean-square millivolts(RMSmv), respectively), while the stability ball produced higher soleus activity over both cushion and flat surfaces(3.97 and 4.24 RMSmv, respectively). Additionally, the cushion elicited higher adductor longus activity over the ball and flat surfaces(1.76 and 1.81 RMSmv, respectively), but no trunk musculature differences were revealed.Conclusion: Compliant surfaces resulted in higher levels of muscular activation in the lower extremities facilitating increased caloric expenditure.Given the increasing trends in sedentary careers and the increases in obesity, this is an important finding to validate the merits of active sitting facilitating increased caloric expenditure and muscle activation. 展开更多
关键词 Energy metabolism ELECTROMYOGRAPHY Female POSTURE Sedentary lifestyle WORKPLACE
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Scan matching using line segment relationships for map-based localization of mobile robot 被引量:1
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作者 葛坤峰 陈卫东 +1 位作者 王景川 冉宇瑶 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第6期757-762,共6页
A new scan matching method for mobile robot localization is presented, which takes line segment as the feature and matches the real scans in the given reference map by relationships of the directional-defined line seg... A new scan matching method for mobile robot localization is presented, which takes line segment as the feature and matches the real scans in the given reference map by relationships of the directional-defined line segments. The alignment was done by hierarchically identifying the multiple relationships and the result was recorded in a correspondence matrix, where the best match is defined and selected for localization. It is indicated that the searching algorithm of the best match can find the ambiguities and get rid of them. This method with less computational cost works well in occluded environment, and can correct the error in pose estimation without the need for the estimation itself. The efficiency, accuracy and robustness of this method were verified by experiments of localization in an occluded environment and a long-distance indoor navigation. 展开更多
关键词 scan matching laser range finder map-based localization mobile robot
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Test Stability of Uster Advanced Fiber Information System(AFIS) 被引量:8
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作者 曹继鹏 鲁琴 +1 位作者 孙鹏子 刘华谱 《Journal of Donghua University(English Edition)》 EI CAS 2010年第3期412-418,共7页
To study test stability of Advanced Fiber Information System(AFIS),card sliver produced in two experiments(12 plans in each experiment)were tested by AFIS.By a statistic analysis of the test results,the number of test... To study test stability of Advanced Fiber Information System(AFIS),card sliver produced in two experiments(12 plans in each experiment)were tested by AFIS.By a statistic analysis of the test results,the number of test times that can get a reliable test reliability(hereinafter this number of test times is referred to as Reliable Test Times,RTT)of test parameters and the coefficient of variation(CV%)values of 30 test results of each experiment plan were obtained.It's concluded that some parameters,such as length,seed coat nep(SCN)size,nep size and immature fiber content(IFC),etc.are very reliable by a test of ten or more times,but other parameters,such as SCN content,trash content,and visible foreign matter(VFM)content,etc.are not reliable until they are tested over 100 times. 展开更多
关键词 Advanced Fiber Information System(AFIS) length NEP impurity reliable test times STABILITY
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Cap rock blast caving of cavity under open pit bench 被引量:4
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作者 Xi-ling LIU Ke-bing LUO +3 位作者 Xi-bing LI Qi-yue LI Wei-hua WANG Feng-qiang GONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第3期648-655,共8页
A laser technique based scanning system was employed to make a comprehensive scanning through borehole forunmapped cavity under open pit bench,then the three-dimensional data will be obtained,and these data were used ... A laser technique based scanning system was employed to make a comprehensive scanning through borehole forunmapped cavity under open pit bench,then the three-dimensional data will be obtained,and these data were used for theoreticalanalysis and numerical simulation to analyze the stability of cap rock.Acoustic emission techniques were also adopted to carry outlong term real time rupture monitoring in cap rock.Therefore,a complete safety evaluation system for the cap rock was establishedto ensure safe operation of subsequent blasting processes.The ideal way of eliminating collapse hazard of such cavity is cap rockcaving through deep-hole blasting,thus,two deep-hole blasting schemes named as vertical deep-hole blasting scheme and one-timeraise driving integrated with deep-hole bench blasting scheme were proposed.The vertical deep-hole blasting scheme has moreexplosive consumption,but the relatively simple blasting net work structure can greatly reduce workloads.However,the one-timeraise driving integrated with deep-hole bench blasting scheme can obviously reduce explosive consumption,but the higher technicalrequirements on drilling,explosive charging and blasting network will increase workloads. 展开更多
关键词 open pit mining CAVITY laser 3D detection cap rock stability evaluation one-time raise driving deep-hole blasting
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Determination of Internal Controls for Quantitative Gene Expression of Isochrysis zhangjiangensis at Nitrogen Stress Condition 被引量:1
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作者 WU Shuang ZHOU Jiannan +1 位作者 CAO Xupeng XUE Song 《Journal of Ocean University of China》 SCIE CAS 2016年第1期137-144,共8页
lsochrysis zhangfiangensis is a potential marine microalga for biodiesel production, which accumulates lipid under ni- trogen limitation conditions, but the mechanism on molecular level is veiled. Quantitative real-ti... lsochrysis zhangfiangensis is a potential marine microalga for biodiesel production, which accumulates lipid under ni- trogen limitation conditions, but the mechanism on molecular level is veiled. Quantitative real-time polymerase chain reaction (qPCR) provides the possibility to investigate the gene expression levels, and a valid reference for data normalization is an essential prerequisite for firing up the analysis. In this study, five housekeeping genes, actin (ACT), α-tubulin (TUA), β-tubulin (TUB), ubiquitin (UBI), 18S rRNA (18S) and one target gene, diacylglycerol acyltransferase (DGAT), were used for determining the reference. By analyzing the stabilities based on calculation of the stability index and on operating the two types of software, geNorm and bestkeeper, it showed that the reference genes widely used in higher plant and microalgae, such as UBI, TUA and 18S, were not the most stable ones in nitrogen-stressed 1. zhangjiangensis, and thus are not suitable for exploring the mRNA expression levels under these experi- mental conditions. Our results show that ACT together with TUB is the most feasible internal control for investigating gene expres- sion under nitrogen-stressed conditions. Our findings will contribute not only to future qPCR studies of/. zhangfiangensis, but also to verification of comparative transcriptomics studies of the microalgae under similar conditions. 展开更多
关键词 CHRYSOPHYTA Isochrysis zhang/iangensis nitrogen deficiency lipid accumulation reference gene selection
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Research on inspection of stability of subsiding area in composite rock-mass roadway 被引量:2
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作者 来兴平 《Journal of Coal Science & Engineering(China)》 2002年第1期21-26,共6页
The research concentrates mainly on the development of failure process in composite rock-mass through acoustic emission, convergence inspection, stress measurement, subside area measurement, level measurement in the p... The research concentrates mainly on the development of failure process in composite rock-mass through acoustic emission, convergence inspection, stress measurement, subside area measurement, level measurement in the process of stability and safety monitoring as well as inspecting of subside area in composite hard rock. In terms of the modern signal analysis technology, various aspects are discussed. The monitoring result and the stability of rock mass can be synthetically evaluated and inferred, and the location of acoustic origin according to the acoustic emission regularity can be successfully detected. Finally the key factors of the deformation can be inferred from in subside area. 展开更多
关键词 composite rock-mass material stability monitoring and inferring acoustic emission
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Synthesis of a novel organic nonlinear optical chromophore and the Testing for μ_gβ Value 被引量:1
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作者 HAN Li-kun JIANG Ya-dong LI Wei CAI Yuan 《Optoelectronics Letters》 EI 2007年第1期50-53,共4页
A novel second-order nonlinear optical chromophore (DCDHF-2-V) was synthesized from 3-Hydroxy-3-methyl-2-butanae, propanedinitrile and 4-diethylaminobenzaldehyde by aldol condensation reaction. Molecular structural ... A novel second-order nonlinear optical chromophore (DCDHF-2-V) was synthesized from 3-Hydroxy-3-methyl-2-butanae, propanedinitrile and 4-diethylaminobenzaldehyde by aldol condensation reaction. Molecular structural characterization was investigated by elemental analysis, FTIR, and 1H-NMR spectra. The melting point obtained from DSC thermogram was almost 251 ℃, and the compound shows a thermal stability up to 270 ℃. Second-order NLO properties of the chromophore were measured by solvatochromic method. From the quantum-mechanical two-level model, it can be obtained that the μgβ value of DCDHF-2-V is 6520×10^-48esu atthe wavelength of 1064 nm. 展开更多
关键词 有机非线光学发色团 合成 μgβ值 测试
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Mixed-Weights Least-Squares Stable Predictive Control Algorithm with Soft and Hard Constraints 被引量:3
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作者 周立芳 邵之江 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第5期565-570,共6页
Mixed-weight least-squares (MWLS) predictive control algorithm, compared with quadratic programming (QP) method, has the advantages of reducing the computer burden, quick calculation speed and dealing with the case in... Mixed-weight least-squares (MWLS) predictive control algorithm, compared with quadratic programming (QP) method, has the advantages of reducing the computer burden, quick calculation speed and dealing with the case in which the optimization is infeasible. But it can only deal with soft constraints. In order to deal with hard constraints and guarantee feasibility, an improved algorithm is proposed by recalculating the setpoint according to the hard constraints before calculating the manipulated variable and MWLS algorithm is used to satisfy the requirement of soft constraints for the system with the input constraints and output constraints. The algorithm can not only guarantee stability of the system and zero steady state error, but also satisfy the hard constraints of input and output variables. The simulation results show the improved algorithm is feasible and effective. 展开更多
关键词 mixed-weight least-squares predictive control soft constraints hard constraints FEASIBILITY
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Study for reasonable value of friction coefficient between main cable and saddle 被引量:2
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作者 Deng Ting Luo Xiheng 《Engineering Sciences》 EI 2012年第3期72-76,共5页
The value of friction coefficient between the main cable and saddle, relates to not only the anti-slippage stability of three-tower suspension bridge, but also the reasonable stiffness of the middle tower and the magn... The value of friction coefficient between the main cable and saddle, relates to not only the anti-slippage stability of three-tower suspension bridge, but also the reasonable stiffness of the middle tower and the magnitude of rigidity of the whole bridge. First, the paper does some comparative studies about the relevant provisions of international norms, and then, summarizes the relevant load test results both at home and abroad. Finally, the paper draws the appropriate anti-slippage safety factor for the most unfavorable load in accordance with international load standards, and discusses the rationality and feasibility of the friction coefficient of 0.2 between main cable and saddle. 展开更多
关键词 three-tower suspension bridge middle tower main cable SADDLE anti-slippage safety factor load standard
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Mechanical response and stability analysis of rock mass in high geostress underground powerhouse caverns subjected to excavation 被引量:15
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作者 LI Biao DING Quan-fu +4 位作者 XU Nu-wen LEI Yi-fan XU Yuan ZHU Zhong-ping LIU Jing-fei 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第10期2971-2984,共14页
To investigate the stability of rock mass in high geostress underground powerhouse caverns subjected to excavation,a microseismic(MS)monitoring system was established and the discrete element method(DEM)-based numeric... To investigate the stability of rock mass in high geostress underground powerhouse caverns subjected to excavation,a microseismic(MS)monitoring system was established and the discrete element method(DEM)-based numerical simulation was carried out.The tempo-spatial damage characteristics of rock mass were analyzed.The evolution laws of MS source parameters during the formation of a rock collapse controlled by high geostress and geological structure were investigated.Additionally,a three-dimensional DEM model of the underground powerhouse caverns was built to reveal the deformation characteristics of rock mass.The results indicated that the MS events induced by excavation of high geostress underground powerhouse caverns occurred frequently.The large-stake crown of the main powerhouse was the main damage area.Prior to the rock collapse,the MS event count and accumulated energy release increased rapidly,while the apparent stress sharply increased and then decreased.The amount and proportion of shear and mixed MS events remarkably increased.The maximum displacement was generally located near the spandrel areas.The MS monitoring data and numerical simulation were in good agreement,which can provide significant references for damage evaluation and disaster forecasting in high geostress underground powerhouse caverns. 展开更多
关键词 high geostress underground powerhouse caverns microseismic monitoring discrete element modelling stability analysis
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Developments and prospects of microseismic monitoring technology in underground metal mines in China 被引量:17
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作者 LIU Jian-po SI Ying-tao +2 位作者 WEI Deng-cheng SHI Hong-xu WANG Ren 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第10期3074-3098,共25页
Microseismic monitoring technology has become an important technique to assess stability of rock mass in metal mines.Due to the special characteristics of underground metal mines in China,including the high tectonic s... Microseismic monitoring technology has become an important technique to assess stability of rock mass in metal mines.Due to the special characteristics of underground metal mines in China,including the high tectonic stress,irregular shape and existence of ore body,and complex mining methods,the application of microseismic technology is more diverse in China compared to other countries,and is more challenging than in other underground structures such as tunnels,hydropower stations and coal mines.Apart from assessing rock mass stability and ground pressure hazards induced by mining process,blasting,water inrush and large scale goaf,microseismic technology is also used to monitor illegal mining,and track personnel location during rescue work.Moreover,microseismic data have been used to optimize mining parameters in some metal mines.The technology is increasingly used to investigate cracking mechanism in the design of rock mass supports.In this paper,the application,research development and related achievements of microseismic technology in underground metal mines in China are summarized.By considering underground mines from the perspective of informatization,automation and intelligentization,future studies should focus on intelligent microseismic data processing method,e.g.,signal identification of microseismic and precise location algorithm,and on the research and development of microseismic equipment.In addition,integrated monitoring and collaborative analysis for rock mass response caused by mining disturbance will have good prospects for future development. 展开更多
关键词 underground metal mine microseismic safety management rock mass stability disaster warning integrated monitoring
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A Simple and Effective Test Method of the Emulsion Stability 被引量:1
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作者 李啸风 陈志荣 +1 位作者 李浩然 韩世钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第2期200-203,共4页
An innovational test method was developed on the basis of redefinition of the emulsion stability. The stability was characterized by relative volume percentage of disperse phase demulsified thoroughly from the top par... An innovational test method was developed on the basis of redefinition of the emulsion stability. The stability was characterized by relative volume percentage of disperse phase demulsified thoroughly from the top part and the bottom part of an emulsion sample, each weighting the same amount, after being settled for a given time at constant temperature. Three series of emulsions were prepared and tested successfully, which were emulsions of paraffin oil and water stabilized with polyoxyethylene lauryl ether series (AEO3 and AEO9) at various HLBs, and emulsions of rapeseed oil and water stablized with sorbitan monoleate (Span80) and each of polyoxyethylene (20) sorbitan carboxylic esters (Tween20, Tween40, Tween60, Tween80 and Tween85) at different HLBs. It provedthat this method is especially workable while the boundaries are opaque in a wide range of HLBs and is capable of offering an accurate optimum HLB. 展开更多
关键词 emulsion stability stability number optimum HLB
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STABILITY OF SOLUTION FOR DYNAMIC GEODETIC NETWORK ADJUSTMENT
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作者 XU Caijun XI Changyuan 《Geo-Spatial Information Science》 2001年第3期9-14,共6页
This paper discusses theoretically the stability of solutions for dynamic geodetic network adjustment,Kalman filtering and sequence adjustment,and two examples are given.The solution for dynamic geodetic network adjus... This paper discusses theoretically the stability of solutions for dynamic geodetic network adjustment,Kalman filtering and sequence adjustment,and two examples are given.The solution for dynamic geodetic network adjustment is stable if the dynamic geodetic network is a classical network.There is not rank deficit in datum,or else the solution is not stable,which will depend on the initial value. 展开更多
关键词 STABILITY dynamic geodetic network INVERSION
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Stable MIMO Constrained Predictive Control with Steadystate Objective Optimization 被引量:7
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作者 黄德先 王京春 金以慧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第4期332-338,共7页
A two-stage multi-objective optimization model-predictive control algorithms(MPC) strategy is presented. A domain MPC controller with input constraints is used to increase freedom for steady-state objective and enhanc... A two-stage multi-objective optimization model-predictive control algorithms(MPC) strategy is presented. A domain MPC controller with input constraints is used to increase freedom for steady-state objective and enhance stabilization of the controller. A steady-state objective optimization algorithm oriented to transient process is adopted to realize optimization of objectives else than dynamic control. It is proved that the stabilization for both dynamic control and steady-state objective optimization can be guaranteed. The theoretical results are demonstrated and discussed using a distillation tower as the model. Theoretical analysis and simulation results show that this control strategy is efficient and provides a good strategic solution to practical process control. 展开更多
关键词 predictive control constraint control optimization stability
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