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Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4, LEI Wei-wei1, 2, GUO Zeng-zhang1, 2, WU Li-xin3, ZHANG Qin4 1. School of Survey and Land Information engineering, Henan Polytechnic university, Jiaozuo 454003, china 2. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003, china 3. college of Resources and civil engineering, Northeastern university, Shenyang 110819, china 4. college of Geology engineering and Geomatics, Chang’an university, Xi’an 710054, china School of Survey and Land Information engineering Henan Polytechnic University Jiaozuo 454003 China college of Geology engineering and Geomatics Chang'an University Xi'an 710054 China Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454003 China college of Resources and civil engineering Northeastern University Shenyang 110819 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

SONIC SPEED AND SHOCK WAVE IN HIGH VELOCITY AERATED FLOWS FROM HIGH HEAD DISCHARGE STRUCTURES

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Journal of Hydrodynamics 2003年第4期15卷 98-103页

作者： Dong Zhi-yong Schood of civil and Architectural engineering, Zhejiang university of Technology, Hangzhou 310014, china Sch. of civil and Arch. Eng. Zhejiang Univ. of Technol. Hangzhou 310014 China

The compressible characteristics in aerated flows at the high velocity ofabout 50m/s were analyzed. Based on the theory of compressible the relations between the sonic speedand shock wave in high-velocity aerated flow were theoretically deduced. And comparisons withmeasured data were made. The theoretical and experimental results show the sonic speed in aeratedflow is merely of the order of several-dozen meters per second, and its minimum value is only 20m/s, which is far much less than that in water or air alone. So high subsonic flow, supersonic flowand transonic flow as well as compression wave, shock wave and expansion wave similarly toaerodnamics may be produced in high velocity aerated flow at the speed of the order of 50m/s. Hencethe influences of these compressible characteristics on high head discharge structures can not beneglected, especially on super high dams over 200m high.

关键词： sonic speed shock wave aerated flow super high dam compressibility

Ventilated Double Skin Facades in Hot-Summer and Cold-Winter Zones in china

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湖南大学学报（自然科学版） 2009年第S1期36卷 160-162页

作者： ZHOU Juan,CHEN You-ming,FANG Shan-shan(college of civil engineering,Hunan university,Changsha,Hunan 410082,china Key Laboratory of Building Safety and Energy Efficiency,MOE,china) college of civil engineering Hunan University Changsha 410082 China Key Laboratory of Building Safety and Energy Efficiency China

Double-skin facades(DSF)are a technique developed for colder climates,so few people think about whether or not it can also be used for hot-summer and cold-winter zones in *** analyzing the problems of using DSF for hot-summer zones,this paper explored on the possibility of applying DSF in hot-summer and cold-winter zones in *** main existing research methods for DSF were also collected and *** properly managed,the ventilated DSF with controlled shading devices can be used even in hot summer in china.

关键词： possibility double-skin facades hot-summer and cold-winter zones simulation method

Source and location mechanism for lode gold deposits hosted in metamorphic rocks in northeastern Hunan, china

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Journal of Central South university of Technology 2001年第2期8卷 108-113页

作者： LIU Liang ming,PENG Sheng lin,YANG Qun zhou (college of Resources, Environment and civil engineering, Central South university, Changsha 410083, china) college of Resources Environment and Civil Engineering Central South University Changsha China

For understanding the source and location mechanism of lode gold deposits hosted in metamorphic rocks in northeastern Hunan, the authors analyzed the REE (rare earth elements) in ores and their host rocks, metallogenic elements in host rocks near and distant from the ore bodies, and characteristics of ore controlling structures, and deduced their genetic implication. Their geochemical features of REE and metallogenic elements suggest that they are formed by mobilization of dispersed metallogenic materials in Lengjiaxi Group of Middle Proterozoic during deformation and metamorphism process, mainly in Wulingian period. From the attributes of ore controlling structures and regularity of location of gold metallization, it is concluded that the location of gold deposits is closely related to reverse shearing. Ore forming fluids are focused on the secondary faults and extension fractures of reverse shear zones of nearly EW strike by stress driven diffusion and seismic pumping.

关键词： lode gold deposit location fluid focus seismic pump northeastern Hunan

Photocatalytic degradation of formaldehyde by diffuser of solar light pipe coated with nanometer titanium dioxide thin films

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Science china(Technological Sciences) 2010年第1期53卷 150-154页

作者： WU YanPeng1,ZHANG WenMing1,MA ChongFang2,LU YuanWei2 & LIU Li1 1 School of civil and Environmental engineering,university of Science and Technology Beijing,Beijing 100083,china 2 college of Environmental and Energy engineering,Beijing university of Technology,Beijing 100022,china School of civil and Environmental engineering University of Science and Technology Beijing

The even and transparent nanometer TiO2 thin films named DegussaP25 as photocatalysis deposited on the surface of diffusers of solar light pipe were prepared by sol-gel *** rugged side of the diffusers of solar light pipe was coated evenly with DegussaP25 solution for the quality of 1.75 *** experiments had showed that when the coated side was away from the sun the lighting degree may be reduced compared with that facing the *** average reduction was only 3.03%,which would not have a significant impact on *** are important parts of a light pipe which can diffuse light evenly to the place needed to be *** experiments showed that in a sunny summer day under the direct sunlight,the solar light pipe combined with photocatalysis could reduce the formaldehyde volume fraction in a box of 0.1 m3 from 1.0×10-6 to 0.16×*** 1 h of photodegradation the formaldehyde volume changed from 1.0×10-6 down to 0.1×10-6 with faster and more complete degradation of *** rate of degradation under cloudy and partly cloudy conditions was slower than that under sunny *** was slower in winter than in summer under sunny *** experimental results also showed that the performance of photocatalysis combined with diffusers of light pipe had better effect in a small *** performance in large space,such as open space,will be the next work in the future,which will be a great challenge.

关键词： solar light pipes diffusers photocatalysis decomposition formaldehyde titanium dioxide

Influence of vibration on granular flowability and its mechanism of aided flow

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Journal of Central South university of Technology 2001年第4期8卷 252-257页

作者： WU Ai xiang,SUN Ye zhi,LI Jian hua (college of Resources, Environment and civil engineering, Central South university, Changsha 410083, china) college of Resources Environment and Civil Engineering Central South University Changsha China

Regarding flowing granular media as weak transverse isotropic media, the phase velocity expressions of wave P, wave SH and wave SV were deduced, the propagation characteristics of waves in flowing granular media were analyzed. The experiments show that vibration has great influence on granular fluidity. The wavefront of wave P is elliptic or closely elliptic, the wavefront of wave SH is elliptic, and the wavefront of wave SV is not elliptic. Wave propagation in the granular flowing field attenuates layer after layer. The theory and experiment both substantiate that the density difference is the key factor which leads to the attenuation of vibrating energy. In terms of characteristics of wave propagation one can deduce that vibrating waves have less influence on flowability of granules when the amplitude and frequency are small. However, when the amplitude and frequency increase gradually, the eccentricity of ellipsoid, the viscosity resistance and inner friction among granules, and shear intensity of granules decrease, and the loosening coefficient of granules increases, which shows the granules have better flowability.

关键词： granular media vibrating aided flow body wave mechanism

Performance-based methodology for assessing seismic vulnerability and capacity of buildings

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Earthquake engineering and engineering Vibration 2010年第2期9卷 157-165页

作者： Lin Shibin1, Xie Lili1, 2,Gong Maosheng1,2 and Li Ming1,3 1.Institute of engineering Mechanics,china Earthquake Administration, Harbin 150080, china 2.School of civil engineering,Harbin Institute of Technology,Harbin 150090, china 3.School of civil engineering,Shenyang Jianzhu university,Shenyang 11016, china Institute of engineering Mechanics China Earthquake Administration Harbin 150080 China

This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved capacity- demand-diagram method. The spectral displacement (Sd) of performance points on a capacity curve is used to estimate the damage level of a building. The relationship between Sd and peak ground acceleration (PGA) is established, and then a new vulnerability function is expressed in terms of PGA. Furthermore, the expected value of the seismic capacity index (SCev) is provided to estimate the seismic capacity of buildings based on the probability distribution of damage levels and the corresponding seismic capacity index. The results indicate that the proposed vulnerability methodology is able to assess seismic damage of a large number of building stock directly and quickly following an earthquake. The SCev provides an effective index to measure the seismic capacity of buildings and illustrate the relationship between the seismic capacity of buildings and seismic action. The estimated result is compared with damage surveys of the cities of Dujiangyan and Jiangyou in the M8.0 Wenchuan earthquake, revealing that the methodology is acceptable for seismic risk assessment and decision making. The primary reasons for discrepancies between the estimated results and the damage surveys are discussed.

关键词： performance-based vulnerability building damage seismic capacity software HAZUS

Effects of Curing Systems on Properties of High Volume Fine Mineral Powder RPC and Appearance of Hydrates

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Journal of Wuhan university of Technology(Materials Science) 2010年第4期25卷 619-623页

作者：刘娟红 college of civil and Environmental engineering University of Science and Technology Beijing

The effects of different curing systems on the properties of high volume fine mineral powder RPC （reactive powder concrete） and the appearances of hydrates were studied. The experimental results show that dry-heating curing promotes the development of pozzolanic reactivity of fine mineral powder; due to low cement content, 0.20 water-bind ratio and high reactive fine mineral powder content, the strength of RPC increases by around 200% after steam curing and subsequent dry-heating curing. Scanning electron microscopy and energy spectrum diagram showed that： after the high volume fine mineral powder RPC with 0.16 water-bind ratio underwent steam curing and dry-heating curing, there was no significant change in the appearance of hydrates; after the RPC with 0.20 water-bind ratio, the cement content of 150 kg/m3 and more steel slag powder underwent dry-heating curing, there was a certain change in the appearance of C-S-H, the structure of gel was more compact and was uniformly distributed, and the Ca/Si of C-S-H gel decreased from 1.41 to around 1.20.

关键词： curing system high volume fine mineral powder RPC appearance of hydrates

Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the Xiangxi Bay

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Science china(Technological Sciences) 2010年第4期53卷 1114-1125页

作者： YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2 & XIAO ShangBin1,3 1 college of civil & Hydroelectric engineering,china Three Gorges university,Yichang 443002,china 2 School of Water Resources & Hydropower engineering,Wuhan university,Wuhan 430072,china 3 Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,china college of civil & Hydroelectric engineering China Three Gorges University School of Water Resources & Hydropower engineering Wuhan University

The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,*** hydrodynamic parameters and water quality parameters(*** velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the Xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 *** water exchange between the mainstream(the Changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different *** water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding ***,the water stability index in the mainstream remained small but it was lowered in the *** main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding *** grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the ***,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.

关键词： impounding density current eutrophication the Xiangxi Bay the Three Gorges Reservoir