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甘露饮的临床加减治验 被引量:6
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作者 黄小芳 《中医临床研究》 2019年第26期130-132,共3页
目的:研究甘露饮对临床各科疾病的功效。方法:对甘露饮治疗男性不育案、慢性咽炎案、糖尿病案、糜烂性胃炎案等临床案例具体分析。结果:四个案例中,其根本病机均以阴虚湿热为主,以甘露饮临床加减治验,效果显著。结论:谨抓异病同治的机理... 目的:研究甘露饮对临床各科疾病的功效。方法:对甘露饮治疗男性不育案、慢性咽炎案、糖尿病案、糜烂性胃炎案等临床案例具体分析。结果:四个案例中,其根本病机均以阴虚湿热为主,以甘露饮临床加减治验,效果显著。结论:谨抓异病同治的机理,将甘露饮广泛应用临床各科疾病,颇有疗效。 展开更多
关键词 甘露饮 临床案例 减治
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基于PA-SA的军事通信网络结构韧性优化研究
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作者 岳地久 李建华 王哲 《军事运筹与评估》 2024年第2期55-62,共8页
基于复杂网络理论建立军事通信网络模型,借鉴刚性物体韧性和外力-形变关系,提出基于韧性势能的军事通信网络结构韧性量化表征;针对蓄意攻击下军事通信网络碎裂过程,提出在“核心节点”和“弱核”之间增边的后验性加边(PA)优化方案;运用... 基于复杂网络理论建立军事通信网络模型,借鉴刚性物体韧性和外力-形变关系,提出基于韧性势能的军事通信网络结构韧性量化表征;针对蓄意攻击下军事通信网络碎裂过程,提出在“核心节点”和“弱核”之间增边的后验性加边(PA)优化方案;运用模拟退火(SA)算法求解最优添边。仿真实验表明,基于PA-SA方法能有效提升军事通信网络结构韧性,且在提升效果、降低时间开销方面具有一定优越性。 展开更多
关键词 军事通信网络 结构韧性 模拟退火
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Strengthening effects of BFRP on reinforced concrete beams 被引量:5
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作者 黄丽华 李宇婧 王跃方 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期182-186,共5页
Reinforced concrete (RC) beams externally bonded with basalt fiber reinforced polymer (BFRP) are experimentally investigated by using different numbers of bonding plies, transverse anchorages as well as the initia... Reinforced concrete (RC) beams externally bonded with basalt fiber reinforced polymer (BFRP) are experimentally investigated by using different numbers of bonding plies, transverse anchorages as well as the initial conditions of strengthened beams. The performances of the BFRP strengthening are compared with those of the carbon fiber reinforced polymer (CFRP) and the glass fiber reinforced polymer (GFRP) under the same experimental condition. Experimental results indicate that the strength and ductility of the strengthened beam with two plies of the BFRP are improved remarkably than those with one ply. The strengthening effects of the BFRP lie between those of the CFRP and the GFRP. The BFRP strengthening is little influenced by pre-cracks of concrete. Most failures are caused by interfaciai debonding induced by flexural cracks in the experiment. Clamping of Uwraps along the whole beam is less efficient than endpoint anchorage for increasing the ultimate load of the strengthened beam. Finally, the models suggested by the five guidelines for predicting the debonding strain of the CFRP are extended to the BFRP and the conservative estimates of the debonding strain of the BFRP are given as well. 展开更多
关键词 basalt fiber reinforced polymer (BFRP) strengthening reinforced concrete beam EXPERIMENT stren^thenin~ zuidelines
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Optimum Constant-stress Plan for Accelerated Life Test with Censoring Ⅱ 被引量:1
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作者 刘瑞元 李和成 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第1期58-64,共7页
In this paper, we obtain the optimum plan by discussing a constant-stress accelerated life test (ALT) satisfying the condition (3.3) at k stresses under an exponential distribution.
关键词 exponential distribution constant-stress accelerated life test accelerating life equation
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Heat transfer model for microwave hot in-place recycling of asphalt pavements 被引量:3
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作者 孙铜生 史金飞 朱松青 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期59-63,共5页
In order to solve for temperature fields in microwave heating for recycling asphalt mixtures, a two-dimensional heat transfer model for the asphalt mixtures within the heating range is built based on the theory of uns... In order to solve for temperature fields in microwave heating for recycling asphalt mixtures, a two-dimensional heat transfer model for the asphalt mixtures within the heating range is built based on the theory of unsteady heat conduction. Four onedimensional heat transfer models are established for the asphalt mixtures outside the heating range, which are simplified into four half-infinite solids. The intensity of the radiation electric field is calculated through experiment by using heating water loads. It is suggested that the mathematical model of boundary conditions can be established in two ways, which are theoretical deduction and experimental reverse. The actual temperature field is achieved by fitting temperatures of different positions collected in the heating experiment. The simulant temperature field, which is solved with the Matlab PDE toolbox, is in good agreement with the actual temperature field. The results indicate that the proposed models have high precision and can be directly used to calculate the temperature distribution of asphalt pavements. 展开更多
关键词 asphalt pavements microwave hot in-place recycling heat transfer model boundary condition intensity of radiation electric field microwave heating experiment
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Fatigue behavior of crane beam strengthened with CFRP 被引量:2
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作者 石启印 李爱群 惠卓 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期561-565,共5页
In order to study the fatigue behavior of the damaged reinforced concrete (RC) beams strengthened by carbon fiber reinforced polymer (CFRP) laminate, three T-shaped beams strengthened by CFRP and one contrasting b... In order to study the fatigue behavior of the damaged reinforced concrete (RC) beams strengthened by carbon fiber reinforced polymer (CFRP) laminate, three T-shaped beams strengthened by CFRP and one contrasting beam are tested under fatigue loading, with the parameters of different modes of strengthening and different fatigue load levels considered. The main results obtained from the tests are: the width of the crack decreases 50. 2% to 66%, and the development of the crack is limited; the stress of steel decreases 24. 1% to 28. 2%, and the stiffness increases 14.9% to 16. 1% after being strengthened. Based on the technical specification for strengthening concrete structures with CFRP and the conclusions from the tests, a calculating scheme of the flexure stiffness is given, which can be used for reference in engineering design. Finally, some suggestions are given for design in fatigue strengthening. 展开更多
关键词 RC crane beam structure strengthening fatigue test carbon fiber reinforced polymer (CFRP)
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Effects of additives on performance of zinc electrode 被引量:2
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作者 程锦 张正富 +2 位作者 赵逸群 禹文龙 侯宏英 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3551-3555,共5页
In order to improve the properties of the nickel?zinc battery and study the effects of the additives on performance of zinc electrode, 3 levels and 4 factors (acetylene black, Bi2O3, PbO, Ca[Zn(OH)3]2·2H2O coated... In order to improve the properties of the nickel?zinc battery and study the effects of the additives on performance of zinc electrode, 3 levels and 4 factors (acetylene black, Bi2O3, PbO, Ca[Zn(OH)3]2·2H2O coated by La(OH)3 ) that affect the zinc electrode were tested with orthogonal design experiments. The charge?discharge experiments of zinc electrode made up of only zinc oxide were done in 20% KOH solution to investigate the function of the additive. In order to better understand the discharge capability attenuation of electrode, the ratios of zinc to calcium in the worst sample and the best sample of the orthogonal design test were analyzed. The samples were characterized by charge?discharge cycling, phase structure analysis, cyclic voltammetry and X-ray diffraction. Experimental evidences indicate that the optimum ratio of electrode additive is as follows: 0.02 g acetylene black, 0.5 g Bi2O3, 0.3 g PbO and 0.2 g Ca[Zn(OH)3]2·2H2O coated with La(OH)3 in 5 g sample. 展开更多
关键词 ADDITIVE nickel-zinc battery orthogonal design experiments zinc electrode
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Life prediction for vacuum fluorescent display using maximum likelihood estimation 被引量:3
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作者 张建平 王睿韬 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期189-192,共4页
In order to obtain the life information of the vacuum fluorescent display (VFD) in a short time, a model of constant stress accelerated life tests (CSALT) is established with its filament temperature increased, an... In order to obtain the life information of the vacuum fluorescent display (VFD) in a short time, a model of constant stress accelerated life tests (CSALT) is established with its filament temperature increased, and four constant stress tests are conducted. The Weibull function is applied to describe the life distribution of the VFD, and the maximum likelihood estimation (MLE) and its iterative flow chart are used to calculate the shape parameters and the scale parameters. Furthermore, the accelerated life equation is determined by the least square method, the Kolmogorov-Smirnov test is performed to verify whether the VFD life meets the Weibull distribution or not, and selfdeveloped software is employed to predict the average life and the reliable life. Statistical data analysis results demonstrate that the test plans are feasible and versatile, that the VFD life follows the Weibull distribution, and that the VFD accelerated model satisfies the linear Arrhenius equation. The proposed method and the estimated life information of the VFD can provide some significant guideline to its manufacturers and customers. 展开更多
关键词 vacuum fluorescent display accelerated life test constant stress Weibull distribution maximum likelihood estimation
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Improved parallel weighted bit-flipping algorithm 被引量:1
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作者 刘晓健 赵春明 吴晓富 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期423-426,共4页
An improved parallel weighted bit-flipping(PWBF) algorithm is presented. To accelerate the information exchanges between check nodes and variable nodes, the bit-flipping step and the check node updating step of the ... An improved parallel weighted bit-flipping(PWBF) algorithm is presented. To accelerate the information exchanges between check nodes and variable nodes, the bit-flipping step and the check node updating step of the original algorithm are parallelized. The simulation experiments demonstrate that the improved PWBF algorithm provides about 0. 1 to 0. 3 dB coding gain over the original PWBF algorithm. And the improved algorithm achieves a higher convergence rate. The choice of the threshold is also discussed, which is used to determine whether a bit should be flipped during each iteration. The appropriate threshold can ensure that most error bits be flipped, and keep the right ones untouched at the same time. The improvement is particularly effective for decoding quasi-cyclic low-density paritycheck(QC-LDPC) codes. 展开更多
关键词 low-density parity-check(LDPC) parallel weighted bit-flipping(PWBF) improved modified weighted bit-flipping (IMWBF) algorithm weighted-sum weighted bit-flipping (WSWBF) algorithm
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Experimental study on concrete columns hybrid reinforced by steel and FRP bars under seismic loading 被引量:1
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作者 孙泽阳 吴刚 +1 位作者 王燕华 吴智深 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期439-444,共6页
In order to study the dynamic behavior of hybrid reinforced concrete columns, shaking table tests of three concrete columns with equal initial stiffness were conducted.The longitudinal reinforcements include an ordina... In order to study the dynamic behavior of hybrid reinforced concrete columns, shaking table tests of three concrete columns with equal initial stiffness were conducted.The longitudinal reinforcements include an ordinary steel bar,a steel-fiber reinforced polymer(FRP) composite bar(SFCB), and hybrid reinforcement(steel bar and FRP bar, CH). Test results show that the peak ground acceleration(PGA) responses of different columns are similar to each other. For an ordinary reinforced concrete(RC) column, the plastic strain of the steel bar develops rapidly after the PGA of the input ground motion reaches 100 cm / s^2, and the corresponding residual strain develops dramatically. For a SFCB column, even after the peak strain reaches 0. 015, the residual strain is below 5 × 10^- 4. For the hybrid column C-H,the residual strain of the FRP bar is similar to that of the SFCB column. In general, concrete columns with hybrid steel and FRP bar reinforcement can achieve smaller residual deformation, and the SFCB reinforced columns can be constructed in extreme environments, such as offshore bridges, due to good anti-corrosion performance. 展开更多
关键词 concrete column shaking table test hybrid reinforcement peak ground acceleration strain distribution
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Test of Feeding Dairy Cows with Chinese Herbal Additive for Improving Production and Quality of Milk 被引量:1
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作者 孙晓萍 刘建斌 李思敏 《Agricultural Science & Technology》 CAS 2017年第4期671-672,共2页
At Baiyin dairy farm, the Chinese herbal additive was added into feed which was then fed to dairy cows from August to October, 2014, and the changes in milk production and quality were observed. The test showed that t... At Baiyin dairy farm, the Chinese herbal additive was added into feed which was then fed to dairy cows from August to October, 2014, and the changes in milk production and quality were observed. The test showed that the additive added into the feed had obvious milk-increasing effect, the milk production was im- proved by 12.67%-17.26%, and the milk quality was improved. The additive has the effects of preventing miscarriage, expelling parasite and preventing diseases. The nutritional components in the feed additive were determined, and the results showed that the contents of protein, crude fat, Ca and P in the additive were 12.29%, 2.66%, 1.8% and 0.22%, respectively. 展开更多
关键词 Chinese herb Feed additive Milk production and quality TEST
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Performance evaluation and chemical property analysis of RWMA binders with 100% artificial reclaimed asphalt 被引量:2
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作者 陈静云 王维营 +2 位作者 孙依人 刘佳音 许斌 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期91-95,共5页
The performance evaluation and chemical property analysis of the recycled warm mix asphalt (RWMA) binders containing 100% artificial reclaimed asphalt ( RA) are presented, and the combined effects of different p... The performance evaluation and chemical property analysis of the recycled warm mix asphalt (RWMA) binders containing 100% artificial reclaimed asphalt ( RA) are presented, and the combined effects of different percentages of the rejuvenator and warm mix additive (WMA) additives on RWMA binders are analyzed through laboratory tests. Three types of WMA additives ad one commercial rejuvenator named GST were selected to restore the artificial RA. The laboratory performace tests including the penetration test, softening test ad rotary, viscosity (RV) test were carried out. In addition, the Fourier transform infrared spectroscopy (FTIR) test was performed to explore the chemical property of RWMA binders. The results of the performance tests indicate that the rejuvenator GST has the ability to restore the artificial RA; choosing the optimum content of WMA additives and rejuvenator is the key to restoring 100% artificial RA, since the combined effects of them play an important role in determining the basic laboratory performance of RWMA binders. The FTIR tests show that the process of recycling mainly adjusts the chemical component of aged asphalt and no remarkable change is observed in the FTI1R spectra of RWMA binders in terms of chemical functional groups with the introduction of WMA additives. 展开更多
关键词 artificial reclaimed asphalt recycled warm mix asphalt WMA aditives rejuvenator performance test Fourier transform infrared spectroscopy
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Experimental study and calculation of flexural capacity of RC beams strengthened with GFRP sheets
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作者 王文炜 李果 《Journal of Southeast University(English Edition)》 EI CAS 2004年第2期229-234,共6页
Nine reinforced concrete (RC) beams strengthened by glass fiber reinforced polymer (GFRP) sheets and three control beams are tested. Four parameters are considered in this experimental program included the concrete st... Nine reinforced concrete (RC) beams strengthened by glass fiber reinforced polymer (GFRP) sheets and three control beams are tested. Four parameters are considered in this experimental program included the concrete strength, the reinforcement ratio, the number of GFRP sheets, and the shear span ratio. It is shown that the application of GFRP sheets can increase the ultimate flexural capacity. The effect of the concrete strength, the reinforcement ratio and the number of GFRP sheets on load capacity is obvious. The shear span ratio can affect the failure mode of RC beams strengthened by GFRP sheets. A theoretical model for flexural behavior of the strengthened RC beam is also developed. 展开更多
关键词 Bending (deformation) Glass fibers Loads (forces) Reinforced concrete
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Large-scale direct shear testing of geocell reinforced soil 被引量:3
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作者 汪益敏 陈页开 刘炜 《Journal of Central South University of Technology》 EI 2008年第6期895-900,共6页
The tests on the shear property of geocell reinforced soils were carried out by using large-scale direct shear equipment with shear-box-dimensions of 500 mm×500 mm×400 mm (length×width×height). Thr... The tests on the shear property of geocell reinforced soils were carried out by using large-scale direct shear equipment with shear-box-dimensions of 500 mm×500 mm×400 mm (length×width×height). Three types of specimens, silty gravel soil, geocell reinforced silty gravel soil and geocell reinforced cement stabilizing silty gravel soil were used to investigate the shear stress-displacement behavior, the shear strength and the strengthening mechanism of geocell reinforced soils. The comparisons of large-scale shear test with triaxial compression test for the same type of soil were conducted to evaluate the influences of testing method on the shear strength as well. The test results show that the unreinforced soil and geocell reinforced soil give similar nonlinear features on the behavior of shear stress and displacement. The geocell reinforced cement stabilizing soil has a quasi-elastic characteristic in the case of normal stress coming up to 1.0 GPa. The tests with the reinforcement of geocell result in an increase of 244% in cohesion, and the tests with the geocell and the cement stabilization result in an increase of 10 times in cohesion compared with the unreinforced soil. The friction angle does not change markedly. The geocell reinforcement develops a large amount of cohesion on the shear strength of soils. 展开更多
关键词 direct shear test GEOCELL reinforced soil shear strength COHESION
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Vacuum preloading combined electroosmotic strengthening of ultra-soft soil 被引量:22
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作者 彭劼 熊雄 +1 位作者 MAHFOUZ A H 宋恩润 《Journal of Central South University》 SCIE EI CAS 2013年第11期3282-3295,共14页
To assess the effectiveness of vacuum preloading combined electroosmotic strengthening of ultra-soft soil and study the mechanism of the process, a comprehensive experimental investigation was performed. A laboratory ... To assess the effectiveness of vacuum preloading combined electroosmotic strengthening of ultra-soft soil and study the mechanism of the process, a comprehensive experimental investigation was performed. A laboratory test cell was designed and applied to evaluate the vacuum preloading combined electroosmosis. Several factors were taken into consideration, including the directions of the electroosmotic current and water induced by vacuum preloading and the replenishment of groundwater from the surrounding area. The results indicate that electroosmosis together with vacuum preloading improve the soil strength greatly, with an increase of approximately 60%, and reduce the water content of the soil on the basis of consolidation of vacuum preloading, howeve~ further settlement is not obvious with only 1.7 mm. The reinforcement effect of vacuum preloading combined electroosmosis is better than that of electroosmosis after vacuum preloading. Elemental analysis using X-ray fluorescence proves that the soil strengthening during electroosmotic period in this work is mainly caused by electroosmosis-induced electrochemical reactions, the concentrations of Al2O3 in the VPCEO region increase by 2.2%, 1.5%, and 0.9% at the anode, the midpoint between the electrodes, and the cathode, respectively. 展开更多
关键词 vacuum preloading electroosmosis laboratory test ultra-soft soil reinforcement effect X-ray fluorescence reinforcement mechanism
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Effects of additives on corrosion and wear resistance of micro-arc oxidation coatings on TiAl alloy 被引量:10
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作者 吴向清 谢发勤 +1 位作者 胡宗纯 王立 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1032-1036,共5页
Ceramic coating was deposited on TiAl alloy substrate by micro-arc oxidation(MAO)in a silicate-aluminate electrolyte solution with additives including sodium citrate,graphite and sodium tungstate.The microstructures a... Ceramic coating was deposited on TiAl alloy substrate by micro-arc oxidation(MAO)in a silicate-aluminate electrolyte solution with additives including sodium citrate,graphite and sodium tungstate.The microstructures and compositions were analyzed by SEM,EDX and XRD.The corrosion and wear properties of the coatings were investigated by potentiodynamic polarization and ball-on-disc wear test,respectively.The results show that the MAO coatings consist of WO3,Ti2O3,graphite and Al2O3 besides Al2TiO5 and Al2SiO5.With additives in the electrolyte,the working voltage at the micro-arc discharge stage decreases,and the ceramic coating gets smoother and more compact.The corrosion current density of MAO coating is much lower than that of TiAl substrate.It can be reduced from 9.81×10-8A/cm 2to 3.02×10-10A/cm 2 .The MAO coatings composed of hard Al2O3,WO3 and Ti2O3 obviously improve the wear resistance of TiAl alloy.The wear rate is-3.27×10-7g/(N·m). 展开更多
关键词 TiAl alloy micro-arc oxidation coating ADDITIVE corrosion resistance wear resistance
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ACCELERATED LIFE TEST STUDIES OF NEW COATED DISPENSER CATHODES 被引量:2
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作者 Zhang Mingchen Zhang Honglai Liu Pukun Su Xiaobao Li Yutao 《Journal of Electronics(China)》 2007年第5期717-720,共4页
The life of impregnated Ba-W cathodes with a new construction have been evaluated using an accelerated life test at three different temperatures (1170℃,1130℃,1090℃) and constant current density (2A/cm^2).According ... The life of impregnated Ba-W cathodes with a new construction have been evaluated using an accelerated life test at three different temperatures (1170℃,1130℃,1090℃) and constant current density (2A/cm^2).According to the relationship of life with operating temperatures,an accelerated equation has been set up.The cathode life at normal operating temperature is deducted based on the accelerated equation.The results show that life of the novel cathode exceeds 190,000 hour at a current density of 2A/cm^2. 展开更多
关键词 Dispenser cathodes Accelerated life test
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Tool Wear Prediction in Micro-end-milling with Hard Material 被引量:1
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作者 李欣 赵学平 +1 位作者 陈杰 门金来 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第3期359-363,共5页
The applications of micro machining have increased drastically in the last ten years. However, tools with less than lmm diameter using for micro-mills have very short and unpredictable life when they are used to cut h... The applications of micro machining have increased drastically in the last ten years. However, tools with less than lmm diameter using for micro-mills have very short and unpredictable life when they are used to cut hard metals. In this study, preliminary design of experiment (DOE) test program was conducted to investigate and i- dentify the factors affecting tool wear at the micro-scale with hard material. Analysis of variance (ANOVA) and Taguchi method were efficient to determine appropriate cutting condition and the effect of parameters. A simple model was also developed to predict the width of slots on the workpiece along the cutting length. The obtained re- suits can provide the basic guidelines for parameter setting of micro-end-milling with hard material. 展开更多
关键词 tool wear micro-end-milling design of experiment (DOE) stainless steel Taguchi method
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Experimental and numerical study on loading rate effects of rock-like material specimens containing two unparallel fissures 被引量:9
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作者 黄彦华 杨圣奇 曾卫 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第6期1474-1485,共12页
A series of laboratory experiments and PFC numerical simulations for rock-like material specimens containing two unparallel fissures were carried out.On the basis of experimental and numerical results,the stress-strai... A series of laboratory experiments and PFC numerical simulations for rock-like material specimens containing two unparallel fissures were carried out.On the basis of experimental and numerical results,the stress-strain curves,mechanical properties,AE events,cracking behavior and energy characteristics were analyzed to reveal the macro-mechanical behavior and meso-mechanism of pre-fissured specimens under different loading rates.Investigated results show that:1)When the loading rate is relatively low,the stress-strain curves show a brittle response.When the loading rate is relatively high,the curve shows a more ductile response.Both of the peak strength and elastic mudulus increase with the increase of loading rate,which can be expressed as power functions.2)Four crack types are identified,i.e.,tensile crack,shear crack,far-field crack and surface spalling.Moreover,the tensile crack,far-field crack and surface spalling are under tensile mechanism,while the shear crack is under shear mechanism.3)The drops of the stress-strain curves all correspond to the crack initiation or coalescence,which is also linked to a sudden increasing in the accumulated micro-crack curve.4)Both of the maximum bond force and energy have the similar trend with the increase of loading rate to peak strength,which indicates that the trend of peak strength can be explained by the meso-mechanics and energy. 展开更多
关键词 rock mechanics two pre-existing fissures strength parameters crack coalescence particle flow simulation
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Effects of different pull-out loading rates on mechanical behaviors and acoustic emission responses of fully grouted bolts 被引量:4
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作者 DU Yun-lou FENG Guo-rui +2 位作者 KANG Hong-pu ZHANG Yu-jiang ZHANG Xi-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第7期2052-2066,共15页
Due to the influence of mining disturbance stress,it is of great significance to better understand the bearing characteristics of fully grouted bolts under different pull-out loading rates.For this purpose,a series of... Due to the influence of mining disturbance stress,it is of great significance to better understand the bearing characteristics of fully grouted bolts under different pull-out loading rates.For this purpose,a series of laboratory pull-out tests were conducted to comprehensively investigate the effects of different pull-out loading rates on the mechanical performance and failure characteristics of fully grouted bolts.The results show that the mechanical performance of the anchored specimen presents obvious loading rate dependence and shear enhancement characteristics.With the increase of the pull-out loading rates,the maximum pull-out load increases,the displacement and time corresponding to the maximum pull-out load decrease.The accumulated acoustic emission(AE)counts,AE energy and AE events all decrease with the increase of the pull-out loading rates.The AE peak frequency has obvious divisional distribution characteristics and the amplitude is mainly distributed between 50-80 dB.With the increase of the pull-out loading rates,the local strain of the anchoring interface increases and the failure of the anchoring interface transfers to the interior of the resin grout.The accumulated AE counts are used to evaluate the damage parameter of the anchoring interface during the whole pull-out process.The analytical results are in good agreement with the experimental results.The research results may provide guidance for the support design and performance monitoring of fully grouted bolts. 展开更多
关键词 fully grouted bolts pull-out test loading rate mechanical behavior AE response failure characteristic
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