The Research of Matching Area Selection Criterion for Gravity Gradient Aided Navigation

Author(s):  
KaiHan Li ◽  
Ling Xiong ◽  
Long Cheng ◽  
Jie Ma
SEG Discovery ◽  
2007 ◽  
pp. 1-15
Author(s):  
Michel Gauthier ◽  
Sylvain Trépanier ◽  
Stephen Gardoll

ABSTRACT One hundred years after the first gold discoveries in the Abitibi subprovince, the Archean James Bay region to the north is experiencing a major exploration boom. Poor geologic coverage in this part of the northeastern Superior province has hindered the application of traditional Abitibi exploration criteria such as crustal-scale faults and “Timiskaming-type” sedimentary rocks. New area selection criteria are needed for successful greenfield exploration in this frontier region, and the use of steep metamorphic gradients is presented as a possible alternative. The statistical robustness of the metamorphic gradient area selection criterion was confirmed by using the curve of the receiver operating characteristic (ROC) to estimate the correlation between metamorphic fronts and the distribution of known Abitibi orogenic gold producers. The criterion was then applied to the James Bay region during a first-pass craton-scale exploration program. This was part of the strategy that led to the discovery of the Eleonore multimillion-ounce gold deposit in 2004.


Author(s):  
M. Avalos-Borja ◽  
K. Heinemann

Weak-beam dark field (WBDF) TEM produces narrowly spaced equal-thickness fringes in wedge-shaped crystals. Using non-systematic diffraction conditions, we have shown elsewhere that simple 2-beam kinematical theory (KT) calculations yield average fringe spacings that are for most practical purposes as satisfactorily accurate as the average spacings obtained from optimized multibeam dynamical theory (DT) calculations, As Fig. 1 shows, this result holds for deviations from the Bragg condition as low as 2x10-1 nm-1, and the differences between the results from the two calculational methods become increasingly insignificant for larger excitation errors. (Unless otherwise noted, all results reported here are for gold crystals, using the 200 beam at 100 KV; the DT calculations were made for 74 beams, using the selection criterion D as discussed in ref. [3]).


2020 ◽  
Vol 25 (3) ◽  
pp. 17-25 ◽  
Author(s):  
G. R. Ramazanov ◽  
L. B. Zavaliy ◽  
L. L. Semenov ◽  
S. A. Abudeev ◽  
A. O. Ptitsyn ◽  
...  

Abstract. Early rehabilitation (ER) of patients with acute cerebrovascular accident (ACA) is one of the priority tasks of the vascular centers; the issue of increasing the volume of rehabilitation measures in the resuscitation and intensive care units (ICU) is relevant. Objective. To evaluate the safety and effectiveness of the progressive ER program in patients with ACA. Material and research methods. The study included 129 patients with ACA in ICU. Each patient of the main group (MGr, n = 61) underwent progressive ER: at least 4–5 vertical adjustments per day, passive mode Kinesiotherapy 49 ± 9.3 minutes, a double load of physiotherapy exercises, preventive physiotherapy; the total time of classes reached 240 minutes per day. In the comparison group (СGr, n = 68), standard ER was performed no more than 120 minutes per day. The groups are comparable by sex, age, severity of the disease and comorbidity. The severity of ACA, the gravity gradient, patient mobility, functional status, degree of dependence, and the presence of complications were evaluated. Results. During a month of work with the MGr, 102 ICU bed-days, 94 days of the artificial lung ventilation use, p < 0.05 were saved. Mortality in MGr decreased -— 8 patients (13.1%) versus 14 (20.6%) in CGr (p < 0.05). In patients within CGr, pulmonary thromboembolism developed in 8.8%, in MGr – in 3.3%. The severity of the apoplectic attack decreased ( by 28% in MGr, and by 20% in CGr ), mobility increased. Comparing the modalities of post resuscitationsyndrome in MGr, it was noted that the score decreased by 2 times from 6 [5; 6] to 3 [2.3; 3.3], but it has not changed in the CGr. Patients in the MGr were 2-–3 days earlier adapted to the vertical adjustment. Conclusions. The progressive ER program in ICU is safe, effective, realisable, and allows reducing the number of bed-days in ICU, the number of days of the artificial lung ventilation use, complications, and mortality in comparison with standard medical care.


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