نتایج جستجو برای: soil attenuation

تعداد نتایج: 229138  

2015
Stefan Mairhofer Craig J. Sturrock Malcolm J. Bennett Sacha J. Mooney Tony P. Pridmore

Root system interactions and competition for resources are active areas of research that contribute to our understanding of how roots perceive and react to environmental conditions. Recent research has shown this complex suite of processes can now be observed in a natural environment (i.e. soil) through the use of X-ray microcomputed tomography (μCT), which allows non-destructive analysis of pl...

Journal: :Chemosphere 2004
Woojin Lee Bill Batchelor

Abiotic reductive dechlorination of chlorinated ethylenes by soil in anaerobic environments was characterized to improve knowledge of the behavior of chlorinated ethylenes in natural systems, including systems modified to promote attenuation of contaminants. Target organics in the soil suspension reached sorption equilibrium in 2 days and the sorption isotherm of target organics was properly de...

2017
Hongmiao Wu Junjian Xu Juanying Wang Xianjin Qin Linkun Wu Zhicheng Li Sheng Lin Weiwei Lin Quan Zhu Muhammad U. Khan Wenxiong Lin

As potent allelochemicals, phenolic acids are believed to be associated with replanting disease and cause microflora shift and structural disorder in the rhizosphere soil of continuously monocultured Radix pseudostellariae. The transcriptome sequencing was used to reveal the mechanisms underlying the differential response of pathogenic bacterium Kosakonia sacchari and beneficial bacterium Bacil...

2005
Hung Leung Wong

The effects of a heavy travelling load on the soil medium and on the adjacent structures were studied. Five soil profiles were analyzed, three from sites in Southern California and two from well documented sites in Europe. It was found that the material damping in the soil layers does not affect attenuation, but rather radiation damping is the most significant. Four of the Five soil profiles st...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علوم کشاورزی و منابع طبیعی گرگان - دانشکده جنگلداری و مهندسی چوب و کاغذ 1391

درک الگوی توزیع مکانی ماکروفون خاک بدلیل اثرات آن روی فرآیندهای اکوسیستم بسیار مهم است. لیکن اطلاعات کمی در این خصوص وجود دارد. درمورد تنوع زیستی ارگانیسم ها وجانداران خاکزی که ازاجزای مهم وکلیدی درهرسیستم اکولوژیکی هستند و در بهبود حاصلخیزی خاک و تولیدات زمین وپایداری اکوسیستم ها(ازطریق فرآیندهای بیولوژیک)نقش عمده دارند تحقیقات کمی انجام شده است. این تحقیق جهت بررسی الگوی مکانی پارامترهای تنوع...

2011
M. E. Pasyanos Michael E. Pasyanos

Attenuation relationships that are used to characterize estimated ground motion often ignore details of the earth’s highly-variable three-dimensional velocity and attenuation structure. Increasingly available attenuation models can be used to refine the expected ground motions. First, some tests are performed to look at the effect of the variability in several parameters, such as crustal attenu...

Abbas Takavar Davood Beiki, Mehdi Sohrabi Mohammad Eftekhari, Mohsen Saghari N Mostaghim

SPECT detects γ-rays from administered radiopharmaceutical within the patient body. γ-rays pass through different tissues before reaching detectors and are attenuated. Attenuation can cause artifacts; therefore different methods are used to minimize attenuation effects. In our study efficacy of Chang method was evaluated for attenuation purpose, using a custom made heart phantom. Due to d...

Maryam Naji Mehdi Momennezhad, Mohsen Hajizadeh Seyed Rasoul Zakavi,

  Introduction: Attenuation correction is a useful process for improving myocardial perfusion SPECT and is dependent on activity and distribution of attenuation coefficients in the body (attenuation map). Attenuation artifacts are a common problem in myocardial perfusion SPECT. The aim of this study was to compare the effect of attenuation correction using different a...

Journal: :Sustainability 2022

For detecting water pipeline leakage signals, in the past people preferred to use sensors obtain signal and then various means methods remove noise increase positioning accuracy. However, as is generated, it spreads along wrapped soil. In this process, will change significantly, eventually becoming very different from original signal. As such, detection accuracy decline, distance becomes longer...

Journal: :IEEE Trans. Geoscience and Remote Sensing 2001
Yan Qing Zeng Qing Huo Liu

Acoustic waves can be a viable tool for the detection and identification of land mines, unexplored ordnance (UXO), and other buried objects. Design of acoustic instruments and interpretation and processing of acoustic measurements call for accurate numerical models to simulate acoustic wave propagation in a heterogeneous soil with buried objects. Compared with the traditional seismic exploratio...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید