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如何写科技论文的“实验方法”
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《实验室科学》 2012年第6期148-148,共1页
在科技类论文中,实验方法(Methods)往往是不可缺少的1节。撰写实验方法部分时总体要把握重点突出,详略得当。对公知公用的方法写明其方法名称即可;引用他人的方法、标准,已有应用而尚未为人们熟悉的新方法等应注明文献出处,并对其方... 在科技类论文中,实验方法(Methods)往往是不可缺少的1节。撰写实验方法部分时总体要把握重点突出,详略得当。对公知公用的方法写明其方法名称即可;引用他人的方法、标准,已有应用而尚未为人们熟悉的新方法等应注明文献出处,并对其方法做简要介绍;对改进或创新部分应详细介绍。 展开更多
关键词 科技论文 '实验方法' 实验技术 研究者
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Research on Dynamic Model's Building of Active Magnetic Suspension Systems 被引量:4
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作者 施建 颜国正 +1 位作者 李黎川 王坤东 《Journal of Donghua University(English Edition)》 EI CAS 2006年第3期131-135,共5页
An experimental method is introduced in this paper to build the dynamics of AMSS (the active magnetic suspension system), which doesn’t depend on system’s physical parameters. The rotor can be reliably suspended und... An experimental method is introduced in this paper to build the dynamics of AMSS (the active magnetic suspension system), which doesn’t depend on system’s physical parameters. The rotor can be reliably suspended under the unit feedback control system designed with the primary dynamic model obtained. Online identification in frequency domain is processed to give the precise model. Comparisons show that the experimental method is much closer to the precise model than the theoretic method based on magnetic circuit law. So this experimental method is a good choice to build the primary dynamic model of AMSS. 展开更多
关键词 active magnetic suspension feedback control dynamic model building experimental method
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Double-porosity rock model and squirt flow in the laboratory frequency band 被引量:8
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作者 巴晶 曹宏 +2 位作者 姚逢昌 聂建新 杨慧珠 《Applied Geophysics》 SCIE CSCD 2008年第4期261-276,共16页
Biot theory research has been extended to the multi-scale heterogeneity in actual rocks. Focused on laboratory frequency bandwidth studies, we discuss the relationships between double-porosity and BISQ wave equations,... Biot theory research has been extended to the multi-scale heterogeneity in actual rocks. Focused on laboratory frequency bandwidth studies, we discuss the relationships between double-porosity and BISQ wave equations, analytically derive the degeneration method for double-porosity's return to BISQ, and give three necessary conditions which the degeneration must satisfy. By introducing dynamic permeability and tortuosity theory, a full set of dynamic double-porosity wave equations are derived. A narrow band approximation is made to simplify the numerical simulation for dynamic double-porosity wavefields. Finally, the pseudo-spectral method is used for wave simulation within the laboratory frequency band (50 kHz). Numerical results have proved the feasibility for dynamic double-porosity's description of squirt flow and the validity of the quasi-static approximation method. 展开更多
关键词 double-porosity rock pseudo-spectral method self-affine fractal microscopicscale mesoscopic scale
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Error Analysis and Compensation of Strapdown Inertial Navigation System 被引量:16
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作者 刘勤 刘莉 祁载康 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期117-120,共4页
Based on error analysis, the influence of error sources on strapdown inertial navigation systems is discussed. And the maximum permissible component tolerances are established. In order to achieve the desired accuracy... Based on error analysis, the influence of error sources on strapdown inertial navigation systems is discussed. And the maximum permissible component tolerances are established. In order to achieve the desired accuracy (defined by circular error probability), the types of appropriate sensors are chosen. The inertial measurement unit (IMU) is composed of those sensors. It is necessary to calibrate the sensors to obtain their error model coefficients of IMU. After calibration tests, the accuracy is calculated by uniform design method and it is proved that the accuracy of IMU is satisfied for the desired goal. 展开更多
关键词 error analysis strapdown inertial navigation system uniform design method calibration test
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Design of the Testing System for Jet Elements
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作者 姚晓先 莫波 李亨标 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期225-228,共4页
To analyze the errors of processing data, the testing principle for jet elements is introduced and the property of testing system is theoretically and experimentally studied. On the basis of the above, the method of p... To analyze the errors of processing data, the testing principle for jet elements is introduced and the property of testing system is theoretically and experimentally studied. On the basis of the above, the method of processing data is presented and the error formulae, which are the functions of the testing system property, are derived. Finally, the methods of reducing the errors are provided. The measured results are in correspondence with the theoretical conclusion. 展开更多
关键词 jet elements error analysis data processing testing method
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Device Robust-Design by Using Response Surface Methodology
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作者 谢晓锋 鲁勇 +1 位作者 张文俊 杨之廉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第8期817-824,共8页
Device robust-design is inherently a multiple-objective optimization problem.Using design of experiments (DoE) combined with response surface methodology (RSM) can satisfy the great incentive to reduce the number of t... Device robust-design is inherently a multiple-objective optimization problem.Using design of experiments (DoE) combined with response surface methodology (RSM) can satisfy the great incentive to reduce the number of technology CAD(TCAD) simulations that need to be performed.However,the errors of RSM models might be large enough to diminish the validity of the results for some nonlinear problems.To find the feasible design space,a new method with objectives-oriented design in generations that takes the errors of RSM model into account is presented.After the augment design of experiments in promising space according to the results of RSM model in current generation,the feasible space will be emerging as the model errors deceasing.The results on FIBMOS examples show that the methodology is efficient. 展开更多
关键词 response surface methodology design of experiments device robust-design
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Microstructural evolution and mechanical properties of Ti-5Al-5Mo-5V-3Cr alloy by heat treatment with continuous temperature gradient 被引量:5
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作者 徐圣航 刘咏 +2 位作者 刘彬 王鑫 陈智星 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第2期273-281,共9页
A new high throughput heat-treatment method with a continuous temperature gradient between 600 and 700 ?C was utilized on the Ti-5553 alloy(Ti-5 Al-5 Mo-5 V-3 Cr, mass fraction, %). The temperature gradient was ind... A new high throughput heat-treatment method with a continuous temperature gradient between 600 and 700 ?C was utilized on the Ti-5553 alloy(Ti-5 Al-5 Mo-5 V-3 Cr, mass fraction, %). The temperature gradient was induced by the variation of the axial section of sample, which was heated by the direct current. The variation of continuous cooling rates on the treated sample was realized by using the end quenching method. The microstructural evolution and mechanical properties under different heat treatment conditions were evaluated. The results show that the pseudo-spinodal decomposition of the alloy occurs at(617±1) ?C, and the size of the precipitated α phase is around 300 nm. Moreover, the highest microhardness is obtained after the heat treatment at the pseudo-spinodal decomposition temperature for 4 h. These indicate that the high throughput method is efficient and fast to determine the phase transformation temperature and corresponding microstructural evolution of alloys. 展开更多
关键词 Ti-5Al-5Mo-5V-3Cr alloy high throughput method pseudo-spinodal decomposition temperature gradient microstructure mechanical properties
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INVESTIGATION ON DRYING CHARACTERISTIC OF MEDICAL PILL USING MICROWAVE-CONVECTIVE DRYING
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作者 余莉 施明恒 朱春玲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第3期220-224,共5页
The combined microwave-convective drying is a novel drying method and has many advantages, such as swift drying, equable drying and sterilization. This paper studies the drying characteristic of medical pill in microw... The combined microwave-convective drying is a novel drying method and has many advantages, such as swift drying, equable drying and sterilization. This paper studies the drying characteristic of medical pill in microwave-convective drying process. The influential parameters of pill drying characteristics including pill size, quality, air velocity, temperature and the input power of microwave, are experimentally investigated. Results show that the drying process is influenced by the intrinsic heat of microwave power, and the environment and the resistance of mass transfer. It has the advantage of the microwave-convective drying in saving energy, reducing labor intensity and sterilizing. The method with the high efficiency is suitable for pharmacy industry. 展开更多
关键词 PILLS microwave-convective drying experimental investigation
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Research on rheological properties of micro-fine grouting cement 被引量:3
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作者 管学茂 王雨利 杨雷 《Journal of Coal Science & Engineering(China)》 2003年第1期67-72,共6页
This article studies the influence of the fineness of cement, fly ash(FA), its composite admixture and the amount and way mixed with superplasticizer on the rheological properties of micro fine cement(MC). By means of... This article studies the influence of the fineness of cement, fly ash(FA), its composite admixture and the amount and way mixed with superplasticizer on the rheological properties of micro fine cement(MC). By means of modern instruments and technologies (such as XRD, SEM, laser granulometer and superficial potential apparatus etc.), the article studies the mineral compositions, the appearance character of grains, particle size distribution and superficial potential of FA and its composite materials. And through that, the reducing mechanism of FA is thoroughly analyzed. The study shows that FA and its composite admixture are excellent components which can effectively improve the rheological properties of micro fine cement, and that the superplasticizer has a saturation point and the mixing way of it has a great influence on the rheological properties. 展开更多
关键词 micro fine cement rheological properties grouting materials
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Vehicle Crashworthiness Simulation Based on Virtual Design of Auto-body 被引量:2
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作者 张晓云 金先龙 +4 位作者 孙奕 林忠钦 周长英 艾维全 王仕达 《Journal of Donghua University(English Edition)》 EI CAS 2004年第2期63-68,共6页
Vehicle crashworthiness simulation is the main component of the virtual auto-body design. One developing commercial vehicle was simulated on crashworthiness by the non-linear finite element method. The bumper crashwor... Vehicle crashworthiness simulation is the main component of the virtual auto-body design. One developing commercial vehicle was simulated on crashworthiness by the non-linear finite element method. The bumper crashworthiness at the speed of 8 km/h was analyzed and valuated. On the other hand, the deformation of the auto-body, the movement of the steering wheel and the dynamic responses of the occupant at the initial velocity of 50 km/h were studied. The results appear that the design of the vehicle could be improved on structure and material. Finally, the frontal longitudinal beam, the main energy-absorbing part of the auto-body, was optimized on structure. Simulation results also show that applying new material, such as high strength steel, and new manufacture techniques, such as tailor-welded blanks could improve the crashworthiness of the vehicle greatly. 展开更多
关键词 Auto-body SIMULATION OPTIMIZATION CRASHWORTHINESS Finite Element Method
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Enhanced Production of Hybrid Extracellular β-Glucanase by Re-combinant Escherichia coli Using Experimental Design Method 被引量:5
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作者 卢英华 邓旭 +2 位作者 程志敬 李清彪 刘刚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第2期172-177,共6页
A genetically engineered Escherichia coli JM109 harboring pLF3 was used to produce a hybrid ex-tracellular β-glucanase. Starting with enzyme production medium, glycerol and yeast extract combined with NaNO3 were scre... A genetically engineered Escherichia coli JM109 harboring pLF3 was used to produce a hybrid ex-tracellular β-glucanase. Starting with enzyme production medium, glycerol and yeast extract combined with NaNO3 were screened to be the most suitable carbon and nitrogen source, respectively. Analysis of six components of the enzyme production medium by employing statistical optimization methods such as Plackett-Burman design and steepest ascent showed that yeast extract was the only significant variable and its best concentration for enzyme production was 12g·L-1. After optimization of the medium, 297.71U·ml-1 of β-glucanase activity in the medium and 352350U·g-1 of β-glucanase selectivity could be obtained, which were 14 and 72 folds higher than those ob-tained from original medium, respectively. Even higher enzyme activities were achieved by batch cultivations in a conventional stirred bioreactor on the optimized medium. 展开更多
关键词 Β-GLUCANASE recombinant Escherichia coli statistical methodology medium optimization
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A novel computational method for protein-protein interaction networks prediction of alpha-synuclein 被引量:1
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作者 谢江 张武 +4 位作者 梅健 顾知立 吴继宗 李辉 张律文 《Journal of Shanghai University(English Edition)》 CAS 2008年第6期501-507,共7页
Alpha-synuclein plays an important role in Parkinson's disease(PD).The current study of alpha-synuclein mainly concentrates at the gene level.However, it is found that the study at the protein level has special si... Alpha-synuclein plays an important role in Parkinson's disease(PD).The current study of alpha-synuclein mainly concentrates at the gene level.However, it is found that the study at the protein level has special significance.Meanwhile, there is free information on the Internet, such as databases and algorithms of protein-protein interactions(PPIs).In this paper, a novel method which integrates distributed heterogeneous data sources and algorithms to predict PPIs for alpha-synuclein in silico is proposed.The PPIs generated by the method take advantage of various experimental data, and indicate new information about PPIs for alpha-synuclein.In the end of this paper, the result illustrates that the method is practical.It is hoped that the prediction result obtained by this method can provide guidance for biological experiments of PPIs for alpha-synuclein to reveal possible mechanisms of PD. 展开更多
关键词 protein-protein interactions (PPIs) ALPHA-SYNUCLEIN heterogeneous data integration computational prediction
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Realization of Perfect Teleportation with W-States in Cavity QED 被引量:1
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作者 HE Juan YE Liu +2 位作者 MA Chi LIU Qi NI Zhi-Xiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期617-620,共4页
We put forward an experimentally feasible protocol for realizing a perfect teleportation by using a class of W-state in QED. The simple way of generating the entangled channel and distinguishing the measurement bases ... We put forward an experimentally feasible protocol for realizing a perfect teleportation by using a class of W-state in QED. The simple way of generating the entangled channel and distinguishing the measurement bases is the distinct feature of our scheme. In addition, the probability of teleportation is up to 100%. The scheme can be implemented by the present cavity QED techniques. 展开更多
关键词 TELEPORTATION W state cavity QED
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Multi-Symplectic Splitting Method for Two-Dimensional Nonlinear Schrodinger Equation 被引量:2
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作者 陈亚铭 朱华君 宋松和 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第10期617-622,共6页
Using the idea of splitting numerical methods and the multi-symplectic methods, we propose a multisymplectic splitting (MSS) method to solve the two-dimensional nonlinear Schrodinger equation (2D-NLSE) in this pap... Using the idea of splitting numerical methods and the multi-symplectic methods, we propose a multisymplectic splitting (MSS) method to solve the two-dimensional nonlinear Schrodinger equation (2D-NLSE) in this paper. It is further shown that the method constructed in this way preserve the global symplectieity exactly. Numerical experiments for the plane wave solution and singular solution of the 2D-NLSE show the accuracy and effectiveness of the proposed method. 展开更多
关键词 splitting method multi-symplectic scheme two-dimensional nonlinear SchrSdinger equation
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Treatment of bauxite residue dust pollution by improving structural stability via application of synthetic and natural polymers 被引量:2
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作者 DING Xu-han XU Guang +1 位作者 ZHOU Wei GUO Xing-yun 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第2期440-448,共9页
The residue drying area(RDA)is the major source of fugitive red sand(RS)dust emissions in the bauxite mining industry and causes serious environmental and safety detriments.Polymer stabilizer(PS)is one of the promisin... The residue drying area(RDA)is the major source of fugitive red sand(RS)dust emissions in the bauxite mining industry and causes serious environmental and safety detriments.Polymer stabilizer(PS)is one of the promising non-traditional stabilizers to mitigate such issues.This research investigated the unconfined compressive strength(UCS)of RS using synthetic polymer stabilizer(SPS)and natural polymer stabilizer(NPS),and to determine the optimum application concentration and mixing ratio of the PAM and Guar gum mixture.Results illustrated that PAM apparently outperform Guar gum in stabilizing sand particles.The mixture of PAM and Guar gum is more effective than individual use.The optimum polymer concentration and the mixing ratio are 0.94 wt.%and 0.6(PAM:total(PAM+Guar gum)),respectively.A rigorous regression model was developed to predict the UCS value based on application concentration and mixing ratio for the purpose of cost and time efficiency. 展开更多
关键词 unconfined compressive strength experimental design POLYACRYLAMIDE Guar gum combined application
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Experimental small bowel preservation using Polysol: A new alternative to University of Wisconsin solution, Celsior and histidine-tryptophan-ketoglutarate solution? 被引量:9
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作者 Lai Wei Koichiro Hata +3 位作者 Benedict Marie Doorschodt Reinhard Büttner Thomas Minor René H Tolba 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第27期3684-3691,共8页
AIM: To evaluate the potential of Polysol, a newly developed preservation solution, in cold storage of small bowel grafts, compared with the current standards, University of Wisconsin solution (UW), Celsior and histid... AIM: To evaluate the potential of Polysol, a newly developed preservation solution, in cold storage of small bowel grafts, compared with the current standards, University of Wisconsin solution (UW), Celsior and histidine-tryptophan-ketoglutarate solution (HTK). METHODS: Male Wistar rats were used as donors. Small bowels were retrieved, flushed and then stored in the respective 4 solutions for 18 h at 4℃. Functional integrity of the grafts was evaluated by isolated reperfusion with oxygenated Krebs-Henseleit buffer at 37℃ for 30 min in all 4 groups. RESULTS: Polysol preservation exhibited the highest tissue ATP concentration and the lowest release of LDH. Malondialdehyde, an index for tissue lipid peroxidation, was also the lowest in Polysol. Tissue oxygen consumption was significantly higher in Polysol than in the others. Of interest, UW-storage promoted 10-fold higher apoptosis than in the others. Moreover, electron microscopy revealed that the mucosal villi/micro-villi formation and the cell organelles, including mitochondria, were both significantly better preserved in Polysol, while deleterious alterations were apparent in the others, most notably in UW. Although Celsior and HTK exhibited the better trend of results than UW in some parameters, but could not reach the over-all superiority to UW.CONCLUSION: Cold storage using Polysol resulted in significantly better integrity and function of small bowel grafts than UW. Hence, Polysol may be a novel alternative for the small bowel preservation. 展开更多
关键词 Small bowel transplantation ISCHEMIA/REPERFUSION Cold storage Polysol University of Wisconsin solution Histidine-tryptophan-ketoglutarate solution Celsior
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Cultivated land information extraction in UAV imagery based on deep convolutional neural network and transfer learning 被引量:14
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作者 LU Heng FU Xiao +3 位作者 LIU Chao LI Long-guo HE Yu-xin LI Nai-wen 《Journal of Mountain Science》 SCIE CSCD 2017年第4期731-741,共11页
The development of precision agriculture demands high accuracy and efficiency of cultivated land information extraction. As a new means of monitoring the ground in recent years, unmanned aerial vehicle (UAV) low-hei... The development of precision agriculture demands high accuracy and efficiency of cultivated land information extraction. As a new means of monitoring the ground in recent years, unmanned aerial vehicle (UAV) low-height remote sensing technique, which is flexible, efficient with low cost and with high resolution, is widely applied to investing various resources. Based on this, a novel extraction method for cultivated land information based on Deep Convolutional Neural Network and Transfer Learning (DTCLE) was proposed. First, linear features (roads and ridges etc.) were excluded based on Deep Convolutional Neural Network (DCNN). Next, feature extraction method learned from DCNN was used to cultivated land information extraction by introducing transfer learning mechanism. Last, cultivated land information extraction results were completed by the DTCLE and eCognifion for cultivated land information extraction (ECLE). The location of the Pengzhou County and Guanghan County, Sichuan Province were selected for the experimental purpose. The experimental results showed that the overall precision for the experimental image 1, 2 and 3 (of extracting cultivated land) with the DTCLE method was 91.7%, 88.1% and 88.2% respectively, and the overall precision of ECLE is 9o.7%, 90.5% and 87.0%, respectively. Accuracy of DTCLE was equivalent to that of ECLE, and also outperformed ECLE in terms of integrity and continuity. 展开更多
关键词 Unmanned aerial vehicle Cultivated land Deep convolutional neural network Transfer learning Information extraction
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Nwomu: Hand-Made Embroidery Technique in Asanteland 被引量:2
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作者 Emmanuel Kodwo Amissah Bernard Asumeng Amoako Osuanyi Quaicoo Essel 《Journal of Literature and Art Studies》 2016年第5期500-511,共12页
The study sought to investigate the historical background of the traditional hand-made embroidery technique, the production process, and its changing trends amongst the Asantes of Ghana. Interview and observation were... The study sought to investigate the historical background of the traditional hand-made embroidery technique, the production process, and its changing trends amongst the Asantes of Ghana. Interview and observation were used in collecting the needed data at selected craft centres in the Kwabre East District, Ejisu-Juaben municipality, Kumasi sub-metro and metropolitan in the Ashanti region of Ghana. The study employed both descriptive and experimental research methods based on the qualitative research approach. It was revealed that Kente and Adinkra enjoy wide reputation and therefore are considered as prestigious clothes. However, Nwomu cloth does not have this fame, only indigenes understand its usage and the philosophy behind its production. In view of this, it is recommended that the elders who are endowed with this unique craft must open their doors to the youth to learn the craft. 展开更多
关键词 Nwomu cloth hand-made EMBROIDERY Asantes satin stitch
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Calculation method of ship collision force on bridge using artificial neural network 被引量:4
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作者 Wei FAN Wan-cheng YUAN Qi-wu FAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第5期614-623,共10页
Ship collision on bridge is a dynamic process featured by high nonlinearity and instantaneity. Calculating ship-bridge collision force typically involves either the use of design-specification-stipulated equivalent st... Ship collision on bridge is a dynamic process featured by high nonlinearity and instantaneity. Calculating ship-bridge collision force typically involves either the use of design-specification-stipulated equivalent static load, or the use of finite element method (FEM) which is more time-consuming and requires supercomputing resources. In this paper, we proposed an alternative approach that combines FEM with artificial neural network (ANN). The radial basis function neural network (RBFNN) employed for calculating the impact force in consideration of ship-bridge collision mechanics. With ship velocity and mass as the input vectors and ship collision force as the output vector, the neural networks for different network parameters are trained by the learning samples obtained from finite element simulation results. The error analyses of the learning and testing samples show that the proposed RBFNN is accurate enough to calculate ship-bridge collision force. The input-output relationship obtained by the RBFNN is essentially consistent with the typical empirical formulae. Finally, a special toolbox is developed for calculation efficiency in application using MATLAB software. 展开更多
关键词 Ship-bridge collision force Finite element method (FEM) Artificial neural network (ANN) Radial basis function neural network (RBFNN)
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Probabilistic analysis of random contact force between geomembrane and granular material 被引量:2
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作者 姜晓桢 束一鸣 《Journal of Central South University》 SCIE EI CAS 2014年第8期3309-3315,共7页
A probabilistic method based on principle of maximum entropy was employed to analyze the randomness of contact force between geomembrane and granular material.The contact force distribution is exponential according to... A probabilistic method based on principle of maximum entropy was employed to analyze the randomness of contact force between geomembrane and granular material.The contact force distribution is exponential according to the proposed method and the grain size is the most important factor that affects the distribution of contact force.The proposed method is then verified by a series of laboratory experiments using glass beads and cobbles as granular material and a very thin pressure,indicating that film is firstly used in these experiments which give a reliable method to measure the contact force at each contact point. 展开更多
关键词 GEOMEMBRANE granular material contact force probability density function
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