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Alireza Sharifi 《Remote sensing letters.》2018,9(6):559-568
Due to various factors which impress wheat growth variability, we need short–term monitoring of biophysical parameters using ultra–high resolution images. These provide an ability to monitor crops at the individual plant level. Two flight missions were carried out at altitude of 40 m with a commercial quad copter and a commercial camera. The images were taken before and after tillage over an 8.8 ha field. The 2 cm orthoimages and surface models were generated using photogrammetric software. Then, the image variables including ratio of the blue and green band, ratio of the red and blue band,ratio of the red and green band, plant height were extracted from orthoimages and surface models. Field measurement included the leaf area index, plant height and biomass for 15 plots each of area 1 m × 1 m. Due to a linear relationship between the biophysical parameters and image variables, it was used a multivariate regression model for modelling. The model using the image variables resulted in coefficient of determination (R2) of 0.95 and the lowest error measures (RMSE = 0.24). The results show that ultra–high resolution images can be used for monitoring of biophysical parameters in wheat crops but it is limited for large area. 相似文献
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Esalatmanesh Kamal Loghman Amirhossein Esalatmanesh Roozbeh Soleimani Zahra Khabbazi Alireza Mahdavi Aida Malek Mousavi Seyed Gholam Abbas 《Clinical rheumatology》2021,40(9):3591-3597
Clinical Rheumatology - Considering the pathologic significance of inflammation and oxidative stress in rheumatoid arthritis (RA) as well as the antioxidant, anti-inflammatory and hypolipidemic... 相似文献
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Gholamigeravand Bahareh Shahidi Siamak Amiri Iraj Samzadeh-kermani Alireza Abbasalipourkabir Roghayeh Soleimani Asl Sara 《Metabolic brain disease》2021,36(6):1259-1266
Metabolic Brain Disease - Alzheimer’s disease is the most common neurodegenerative disease associated with deposition of amyloid-beta and the increased oxidative stress. High free radical... 相似文献
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Malek Mahdavi Aida Khalili Afshin Alihosseini Samin Jaberinezhad Mehran Esalatmanesh Kamal Hajialilo Mehrzad Seyedmardani Seyedmostafa Khabbazi Alireza 《Clinical rheumatology》2021,40(10):3941-3949
Clinical Rheumatology - Adult-onset Still’s disease (AOSD) characterized by a high spiking fever, skin rash, arthritis, and leukocytosis. The aim of the present study was considering the... 相似文献
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Salar Sajedi Alireza Kamal Asl Mohammad R. Ay Mohammad H. Farahani Arman Rahmim 《Medical engineering & physics》2013,35(6):754-764
Applications in imaging and spectroscopy rely on pulse processing methods for appropriate data generation. Often, the particular method utilized does not highly impact data quality, whereas in some scenarios, such as in the presence of high count rates or high frequency pulses, this issue merits extra consideration. In the present study, a new approach for pulse processing in nuclear medicine imaging and spectroscopy is introduced and evaluated. The new non-linear recursive filter (NLRF) performs nonlinear processing of the input signal and extracts the main pulse characteristics, having the powerful ability to recover pulses that would ordinarily result in pulse pile-up. The filter design defines sampling frequencies lower than the Nyquist frequency.In the literature, for systems involving NaI(Tl) detectors and photomultiplier tubes (PMTs), with a signal bandwidth considered as 15 MHz, the sampling frequency should be at least 30 MHz (the Nyquist rate), whereas in the present work, a sampling rate of 3.3 MHz was shown to yield very promising results. This was obtained by exploiting the known shape feature instead of utilizing a general sampling algorithm. The simulation and experimental results show that the proposed filter enhances count rates in spectroscopy. With this filter, the system behaves almost identically as a general pulse detection system with a dead time considerably reduced to the new sampling time (300 ns). Furthermore, because of its unique feature for determining exact event times, the method could prove very useful in time-of-flight PET imaging. 相似文献
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