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Experimental research on grouser traction of deep-sea mining machine

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Applied Mathematics and Mechanics(English Edition) 2015年第9期36卷 1243-1252页

作者： Wenbo MA Qiuhua RAO kang feng feng XU School of Civil Engineering Central South University

The traction characteristics of the grouser, cutting the simulative soil of deepsea sediment, with different tooth widths, tooth heights, and ground pressures are studied with traction characteristic test apparatus. A traction-displacement model is obtained by combining the analysis of the cutting mechanism. The results show that the tractiondisplacement curves of grousers with different tooth widths, tooth heights, and ground pressures have the same changing trend, which matches the Wong traction model. Their sensitivity coefficient and shear modulus are slightly fluctuated. Therefore, the average values can be used as the traction model parameters. The maximum traction of the grouser with a two-side edge and a 10 mm tooth width increment changing with the tooth height and ground pressure can be determined according to the grousers with different tooth widths. By combining the traction model parameters, the traction-displacement curve of the grouser with a certain group values of tooth width, tooth height, and ground pressure can be predicted. Therefore, the slip of the mining machine can be prevented to improve the mining efficiency.

关键词： deep-sea sediment simulative soil traction test deep-sea mining machine,grouser traction model

Experiment and Numerical Simulation of Free Water Jet by a Central-body Nozzle

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Chinese Journal of Mechanical Engineering 2010年第6期23卷 797-804页

作者： YANG Minguan ZHANG feng kang Can GAO Bo School of Energy and Power Engineering Jiangsu University Zhenjiang 212013 China

The recent research about cavitation jet mainly focuses on the organ-pipe nozzle and triangular nozzle. The research content mainly includes the optimized design about the structure of nozzles, the observation and flow analysis about the cavitation jet in the water, and the theory of rock attacked by the cavitation jet, while the energy characteristic of the free jet is not studied yet. In China, the research about the central-body nozzle is almost empty. For the purpose of studying the energy characteristic and the structure of free water jet discharged from central-body nozzle, an experiment with phase Doppler particle anemometry（PDPA） technology is carried out to measure the free water jet flow, which is produced by a central-body nozzle under the jet pressure of 15 MPa. While five sections with different axial distances from the nozzle outlet are selected for data process and analysis, the axial and radial velocity and the droplets of the particle size are studied. Meanwhile, numerical calculation of corresponding flow field is conducted by using volume of fluid（VOF） multiphase model, and the jet flow feature is discussed. The experimental and calculating results show that the axial velocity of high speed jet flow dissipates slowly in the air, and the core area and diffused area are discovered. The diameter of droplet in the core area is small, and jet energy is concentrated, while in the diffusion area, water is mingled with ambient air and radial velocity is relatively large. Obvious low-pressure area exists behind the central body and potential cavitation may occur in that area. The proposed research reveals the energy characteristic of free jet discharged from central-body nozzle, provides the theoretical basis for preestimating erosion feature of the central-body nozzle and also the theoretical foundation for revealing the mechanism of erosion.

关键词： central-body nozzle free water jet phase Doppler particle anemometry(PDPA) energy characteristic VOF model

Evaluation of grapevine sucker segmentation algorithms for precision targeted spray

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International Journal of Agricultural and Biological Engineering 2015年第4期8卷 77-85,I0002页

作者： Xu Shasha Li Wenbin kang feng Zheng Yongjun Lan Yubin School of Technology Beijing Forestry UniversityBeijing 100083China College of Engineering China Agricultural UniversityBeijing 100083China College of Engineering South China Agricultural UniversityGuangzhou 510642China

Chemical sucker control has been proven to be an effective substitute for manual and mechanical *** and location of suckers is the key technology of precision targeted spray which can reduce spray volume than current spray *** goal of this research was to develop a quick and effective segmentation algorithm of sucker images for real-time mobile targeted spray by evaluating and comparing seven segmentation algorithms categorized into segmentation based on color feature(ExG,ExGExR,and CIVE),K-means clustering segmentation in CIE L*a*b*space(K-Lab),and mean shift clustering segmentation based on color feature(ExG-MS,ExGExR-MS,and CIVE-MS)from time consuming and *** results indicated that ExGExR and CIVE took shorter time than other algorithms,and were more suitable for real-time *** further evaluating segmentation accuracy,ExGExR,CIVE,and mean shift algorithms were acceptable to kill *** ExGExR was the best algorithm for sucker segmentation in consideration of time consuming and accuracy,next came CIVE.

关键词： grapevine suckers image segmentation color feature K-means mean shift

Degradation of a fullerene end-capped polycaprolactone by lipase AK

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Chinese Science Bulletin 2010年第29期55卷 3279-3282页

作者： PENG QiYun kang feng LI Juan YANG XinLin School of Life Science and Technology Beijing Institute of Technology Beijing 100081 China

Using titrimetric method,enzymatic behavior of lipase AK against fullerene end-capped polycaprolactone(C60-PCL) was studied for the first time,compared with polycaprolactone(PCL).The results showed that degradation of both C60-PCL and PCL by lipase followed Mechaelis-Menten equation,with the degradation parameters of PCL and C60-PCL were 0.75 mg mL-1 and 0.16 mg mL-1 for Km,and 0.90 mL h-1 and 0.43 mL h-1 for Vmax,respectively.C60-PCL had a slower degradation rate than PCL under the same *** data indicated that the introduction of fullerene enabled PCL hard to be degraded by lipase.

关键词：聚己内酯脂肪酶富勒烯降解酶封端 PCL C60 米氏方程

Influence of Residual Stress on the Dimensional Instability of 7075 Aluminum Cone-Shaped Shells

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稀有金属材料与工程 2009年第A03期38卷 91-94页

作者： Wang Qiucheng Zhao Zude Wang Yisi Xing Hongyan kang feng MOE Key Lab of Mechanical Manufacture ＆Automation Zhejiang University of Technology Hangzhou 310032 China No.59 institute of China Ordnance Industry Chongqing 400039 China

This paper dealt with the influence of residual stress on the dimensional instability of 7075 aluminum cone-shaped shells. Finite element method was introduced to calculate residual stress distributions in 7075 aluminum cone-shaped shells during conventional heat treatment (CHT) and deep cryogenic treatment (DCT). An example was given to demonstrate effects of deep cryogenic treatment (DCT) and conventional heat treatment (CHT) on dimensional instability. It is concluded that initial residual stresses have detrimental influence on the dimensional instability of 7075 aluminum cone-shaped shells.

关键词：残余应力铝合金有限元分析物理性能

Design of an air-slot mode-gap nanocavity in a two dimensional photonic crystal slab

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Chinese Science Bulletin 2013年第1期58卷 63-67页

作者： REN Cheng kang feng GAN Lin feng Shuai CHENG Lifeng LI ZhiYuan School of Opto-Electronic Information Science and Technology Yantai University Wenjing College Yantai University Optical Physics Laboratory Institute of PhysicsChinese Academy of Sciences Academy of Science Minzu University of China

We present a novel and simple design of an air-slot mode-gap photonic crystal(PC) nanocavity by introducing a linear air slot to the center of a line-defect waveguide in a two dimensional triangular-lattice silicon PC slab.A high quality factor(Q factor) of 8.42*105 and an ultrasmall mode volume of 0.998 cubic wavelength are achieved in an optimized air-slot nanocavity which is a suitable choice for the strong matter-field interaction in free *** high Q cavities with ultrasmall mode volume are important for applications such as quantum computation and nonlinear optics.

关键词：二维光子晶体空气槽腔设计非线性光学差距高品质因数强相互作用自由空间

Energy‐based analysis of seismic damage mechanism of multi‐anchor piles in tunnel crossing landslide area

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Deep Underground Science and Engineering 2023年第3期2卷 245-261页

作者： Hong Wei Honggang Wu Guojun Ren Lin Tang kang feng College of Resource and Environment Engineering Guizhou UniversityGuiyangChina China Northwest Research Institute Co.Ltd.of CREC LanzhouChina College of Civil Engineering and Architecture Southwest University of Science and TechnologyMianyangChina

To study the damage mechanism of multi‐anchor piles in tunnel crossing landslide area under earthquake,the damping performance of multi‐anchor piles was *** energy dissipation springs were used as the optimization device of the anchor head to carry out the shaking table comparison test on the reinforced *** Hilbert spectrum and Hilbert marginal spectrum were proposed to analyze the seismic damage mechanism of the multi‐anchor piles,and the peak Fourier spectrum amplitude(PFSA)was used to verify the effectiveness of the *** results show that the seismic energy is concentrated in the high‐frequency component(30-40Hz)of the Hilbert spectrum and the low‐frequency component(12-30 Hz)of the marginal *** indicates that they can be combined with the distribution law of the PFSA to identify the overall and local dynamic responses of the multi‐anchored piles,*** stretchable deformation of the energy‐dissipation springs improves the coordination of the multi‐anchor piles,resulting in better pile *** damage mechanism of the multi‐anchor piles is elucidated based on the energy method:local damage at the top and middle areas of the multi‐anchor piles is mainly caused by the low‐frequency component(12-30 Hz)of the marginal spectrum under the action of 0.15g and 0.20g seismic *** the seismic intensity increases to 0.30g,the dynamic response of the slope is further amplified by the high‐frequency component(30-40 Hz)of the Hilbert energy spectrum,which leads to the overall damage of the multi‐anchor piles.

关键词： Hilbert-Huang transform marginal spectrum multi‐anchor piles seismic damage mechanism

Application of a new basalt fiber-reinforced polymer anchorage structure in the tunnel–slope system under rainfall action

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Journal of Mountain Science 2023年第2期20卷 570-584页

作者： TANG Lin WU Hong-gang WEI Hong feng kang RENG Guo-jun College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China China Northwest Research Institute Co.Ltd.of CREC Lanzhou 730070China College of Civil Engineering and Architecture Southwest University of Science and TechnologyMianyang 621000China

The application of basalt fiber-reinforced polymer(BFRP)anchors has gained significant attention,particularly in the field of geotechnical anchorage engineering because of its high strength and corrosion *** research on the applicability of BFRP anchor in a tunnel–slope system under rainfall is of practical significance to solve the problem of instability damage to anchored slopes caused by corrosion of steel *** this study,model tests of BFRP and steel anchorage structures were conducted to compare their reinforcement capability in a tunnel–slope system under heavy *** results show that the BFRP anchorage structure is better than the steel in coordinating slope deformation and stabilizing earth pressure around the *** deformation of slopes under rainfall is classified into four stages:initial,isokinetic,accelerated,and blocked *** anchors have the same axial strain distribution pattern as the steel anchors,and they are convexly distributed along the axial direction of the *** correlation analysis and Pearson linear correlation analysis of the multi-attribute data of the slope and BFRP anchors showed a positive correlation among BFRP anchor strain,earth pressure inside the slope,slope deformation displacement,and accumulated *** research results provide a basis and reference for the application of BFRP anchors in the anchorage engineering of the tunnel–slope system under rainfall action.

关键词： BFRP anchors Steel anchors Rainfall Tunnel-slope system

Frequency stabilization in FBG external cavity semiconductor laser based on acetylene absorption method

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Optoelectronics Letters 2008年第5期4卷 335-338页

作者： Li Zhi-quan Su feng-yan kang Li-li College of Electrical Engineering Yanshan University Qinhuangdao 066004 China

A frequency-stabilized 1.53 μm FBG external-cavity semiconductor laser by using acetylene absorption is presented and its basic principles are introduced. Graded refractive index fiber and pigtailed fiber are used in the absorption air chamber to enhance the coupling stability. The impact of the background power is eliminated by using the third-harmonic mode-locking technique. A lock-in amplifier is utilized to ensure that the output laser wavelength is locked at the C2H2 absorption line of 1530.37 nm. The frequency stability reaches 10-8 within 24 h.

关键词：稳频激光器半导体乙炔吸收