The Brazilian Amazon has a deficit of 35% of coverage regarding topographic mapping at semi-detailed (1:100,000) scale. This paper presents an alternative to overcome this scenario using a combination of planialtimetric information from two orbital SAR (Synthetic Aperture Radar) missions. The altimetry was acquired from Shuttle Radar Topography Mission (SRTM), while the planimetry was provided ...

The Shuttle Radar Topography Mission SRTM produced the first global digital elevation model (DEM) data set of the world’s topography in the year 2000. The data set covers regions between ±60 degrees latitude with a resolution of 30 meters. The 90 % height accuracy in these regions is on the range of 6 meters, limited by the baseline length, the metrology and the instrument noise. In mountainous...

This study makes contributions toward development of accurate DEM from ground and satellite data over South Africa. is achieved by preparing recent satellite-based DEMs (AW3D30, SRTM, ASTER, TanDEM-X, MERIT), assessing their vertical accuracy, selecting candidate DEMs, modelling errors for the fusing DEMs. Following removal outliers each DEM, a different number levelling are used in assessment ...

Bài báo đề cập đến việc cải thiện độ chính xác của mô hình số cao (Digital Elevation Model - DEM). Mặc dù, các thuật toán tái chia mẫu song tuyến, bicubic, Kriging và tăng phân giải bằng mạng nơ ron Hopfield (HNN) cho phép nâng cao, đặc biệt là từ nguồn dữ liệu toàn cầu như SRTM, ASTER, v.v., sự tham gia bổ sung cũng có thể hơn nữa cao. này xuất một HNN với hàm hiệu chỉnh thay đổi điều kiện ràn...

BACKGROUND AD is a progressive neurodegenerative disorder that is associated with the accumulation of two different insoluble protein aggregates, Aβ plaques and hyperphosphorylated tau. This study aimed to investigate the optimal acquisition and quantification of [18F]AV45 and [18F]AV1451 to image Aβ and tau, respectively, in subjects with AD. Fifteen subjects with early stage AD underwent a T1...

We examined the reproducibility of using the constant infusion paradigm for equilibrium measurement of D2/3 receptors using [ C](+)-propyl-hexahydro-naphtho-oxazin (PHNO) positron emission tomography (PET). Six subjects were scanned with a bolus plus constant infusion (Kbol 5 80 minutes) of [ C]-(+)-PHNO. Binding potential (BPND) was computed using the equilibrium approach and compared to a sim...

Digital elevation models (DEMs) have become a recognized tool in the visualization of his torical sites. Applications range through various scales from 3D presentations of the settings of individual buildings up to detailed GIS analysis of the hinterlands of archaeological sites. However, the development of space-borne instruments has seen the rise of high resolution DEMs even on the global sca...

UNLABELLED It has been demonstrated in vitro that the dopamine D(2) receptor has 2 interconvertible affinity states for endogenous dopamine, referred to as the high- and the low-affinity states. (11)C-(R)-2-CH(3)O-N-n-propylnorapomorphine ((11)C-MNPA) is a new agonist radioligand for in vivo imaging of the high-affinity state of dopamine D(2) receptors using PET. In the present study, the kinet...

UNLABELLED 11C-(R)-PK11195 is a PET radiotracer for the quantification of peripheral benzodiazepine binding sites (PBBSs). The PBBS is a consistent marker of activated microglia, and 11C-(R)-PK11195 has been used to image microglial activity in the diseased brain and in neoplasia. However, the PBBS is also expressed in the brain vasculature (endothelium and smooth muscles), and no evidence, to ...