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Effects of soil profile and characteristic of exciting force on propagation of ground vibrations
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作者 Sunao KUNIMATSU Yoshihiro HIRAO Yasutoshi KITAMURA 《Journal of Modern Transportation》 2012年第3期129-137,共9页
Ground-borne vibrations caused by vibration sources such as road traffic and construction exhibit complicated properties during propagation from the vibration source to the inside of a building. In the present paper, ... Ground-borne vibrations caused by vibration sources such as road traffic and construction exhibit complicated properties during propagation from the vibration source to the inside of a building. In the present paper, a numerical analysis technique for the system of vibration source and propagation path of ground vibration is developed in order to systematically determine the propagation properties of the vibration as part of developing a predictive technique for exposure evaluations by vibrations in three directions at receiving points of vibration in the human body. First, the exciting forces in three directions for input into the numerical computation are inversely-estimated by using the measured acceleration rec- ords of the measurement points, which are near the vibration source. The thin-layered element method is used for numerical computation of the ground vibration. Then, the calculation results for the ground vibration obtained by using the estimated exciting force are compared with the measured results, and the influence of the stratified structure of the ground on the exciting force and the propagation properties of the ground vibration are studied. From these results, in a prediction of the ground vibration in three directions, it is emphasized that it is necessary to consider the influence of horizontal exciting force, although attention has been paid to only the vertical exciting force for simulating ground vibration. 展开更多
关键词 ground-borne vibration vibration source exciting force stratified structure soil profile
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Assessment of Rhizospheric Microorganisms of Transgenic Populus tomentosa with Cowpea Trypsin Inhibitor (CpTI) Gene 被引量:1
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作者 Zhang Qian Zhang Zhi-yi Lin Shan-zhi Lin Yuan-Zhen Yang Le 《Forestry Studies in China》 CAS 2005年第3期28-34,共7页
To have a preliminary insight into biosafety of genetically transformed hybrid triploid poplars (Populus tomentosa × P bolleana)× P. tomentosa with the cowpea trypsin inhibitor (CpTD gene, two layers of r... To have a preliminary insight into biosafety of genetically transformed hybrid triploid poplars (Populus tomentosa × P bolleana)× P. tomentosa with the cowpea trypsin inhibitor (CpTD gene, two layers of rhizospheric soil (from 0 to 20cm deep and from 20 to 40cm deep, respectively) were collected for microorganism culture, counting assay and PCR analysis to assess the potential impact of transgenic poplars on non-target microorganism population and transgene dispersal. When the same soil layer of suspension stock solution was diluted at both 1:1000 and 1:10000 rates, there were no significant differences in bacterium colony numbers between the inoculation plates of both transgenic and non-transgenic poplars. The uniform results were revealed for both soil layer suspension solutions of identical poplars at both dilution rates except for non-transgenic poplars at 1:10000 dilution rates from the same type of soil. No significant variation in morphology of both Gram-positive and Gram-negative bacteria was observed under the microscope. The potential transgene dispersal from root exudates or fallen leaves to non-target microbes was repudiated by PCR analysis, in which no CpTI gene specific DNA band was amplified for 15 sites of transgenic rhizospheric soil samples. It can be concluded that transgenic poplar with the CpTI gene has no severe impact on rhizospheric microorganisms and is tentatively safe to surrounding soil micro-ecosystem. 展开更多
关键词 transgenic poplar CpTI gene rhizospheric microorganisms ecological risk soil profile
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Land classification for choice of tree species on farm lands in the Attock District of Punjab, Pakistan
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作者 Syed Muhammad Akmal RAHIM Shahida HASNAIN Farkhanda JABEEN 《Forestry Studies in China》 CAS 2011年第4期290-298,共9页
In Pakistan, particularly in Punjab Province, it is difficult for agrofarmers to combine their indigenous knowledge and modern scientific methods to evaluate existing traditional farming systems and forestry practices... In Pakistan, particularly in Punjab Province, it is difficult for agrofarmers to combine their indigenous knowledge and modern scientific methods to evaluate existing traditional farming systems and forestry practices. This requires an evaluation of indigenous soil classification in simple terms along with knowledge of the local flora, especially trees. This study focuses on land suitability classification for trees in the Attock District of Punjab, Pakistan. A survey was conducted which included interviews of local agrofarmers as well as standard soil analyses including both chemical and physical determinations of local soil types. An evaluation of soil types for cultivation of various crops was carried out given its total extent, component soil series and their proportions, spotting characteristics of each soil series and their major limitations/hazards for trees/crops. These would lead to the identification of various tree species according to soil characteristics. Then, according to the soil types and species, a land suitability map was obtained for the choice of tree species by using geographic information system (GIS) software. Land suitability classification will help local agroforesters/agrofarmers in matching suitable agricultural trees/crops properly for different soils in the area. 展开更多
关键词 AGROFORESTRY land suitability classification agro-ecological zones soil profile
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