scholarly journals Approaches to assessing the effectiveness of earthquake predictions using the LURR (load-unload response ratio) method on Sakhalin

2021 ◽  
Vol 946 (1) ◽  
pp. 012010
Author(s):  
A S Zakupin
Keyword(s):  
Retrospective Analysis ◽  
Analytical Dependence ◽  
Random Sets ◽  
Real Sample ◽  
Ratio Method ◽  
Response Ratio ◽  
Earthquake Predictions ◽  
Spatio Temporal ◽  
Practical Recommendations

Abstract A retrospective analysis of the seismicity of Sakhalin from 1997 to 2019 was performed to demonstrate the possibilities of the LURR technique recently in previous our work. The following results were obtained: 84 % of earthquakes (16 out of 19, with M ≥ 5) are predicted, 25% alarms (4 out of 15 predicted areas) were false. This paper proposes an analytical dependence to describe the forecast effectiveness (Ke) for this research. The extremes of Ke were found at the value of the alarm period of 12 and 24 months. At the same time, Ke is significantly higher for the alarm period of 24 months and decreases after a two-year alarm period. Another way to prove the results obtained is the random spatio-temporal distributions of the predicted objects (19 earthquakes with M ≥ 5). 10 such random sets have been assigned to 15 predicted areas, the result shows a significant advantage of a real sample over random ones, and also practically confirms the reliability of the algorithm for using the LURR technique. The methodology and results of this work can serve as practical recommendations for working with the LURR method for seismologists.

scholarly journals Comparative analysis of hemorrhagic fever with renal syndrome (HFRS) foci in the Saratov region

2015 ◽  
Vol 20 (4) ◽  
pp. 22-25
Author(s):  
A. V Ryabova ◽  
M. A Tarasov ◽  
K. S Zakharov ◽  
N. V Popov
Keyword(s):  
Remote Sensing ◽  
Comparative Analysis ◽  
Spatial Structure ◽  
Retrospective Analysis ◽  
Hemorrhagic Fever ◽  
Saratov Region ◽  
The Earth ◽  
Temporal Features ◽  
Spatio Temporal

The aim of the research was the assessment of the level ofa potential epidemic danger of the anthropourgic foci of hemorrhagic fever with renal syndrome (HFRS) in the cities of Saratov and Atkarsk ofthe Saratov region. There was performed a comparative retrospective analysis of data of epizootological monitoring of focal territories for the period from 1999 to 2014. For the detection of the spatial structure of HFRS foci there were used methods of remote sensing of the Earth. As a result, there have been revealed spatio-temporal features of an activity of HFRS foci in suburbs, some hallmarks of landscape and biocenotic structure were established.

scholarly journals Failure Potential Evaluation in Engineering Experiments Using Load/Unload Response Ratio Method

2011 ◽  
Vol 170 (1-2) ◽  
pp. 237-245 ◽  
Author(s):  
Lang-ping Zhang ◽  
Huai-zhong Yu ◽  
Xiang-chu Yin
Keyword(s):  
Ratio Method ◽  
Response Ratio ◽  
Potential Evaluation

scholarly journals Fine-Scale Space-Time Cluster Detection of COVID-19 in Mainland China Using Retrospective Analysis

2021 ◽  
Vol 18 (7) ◽  
pp. 3583
Author(s):  
Min Xu ◽  
Chunxiang Cao ◽  
Xin Zhang ◽  
Hui Lin ◽  
Zhong Yao ◽  
...  
Keyword(s):  
Retrospective Analysis ◽  
Disease Incidence ◽  
Mainland China ◽  
Scale Space ◽  
Space Time ◽  
The Family ◽  
Family Level ◽  
The Usa ◽  
Spatio Temporal ◽  
And Control

Exploring spatio-temporal patterns of disease incidence can help to identify areas of significantly elevated or decreased risk, providing potential etiologic clues. The study uses the retrospective analysis of space-time scan statistic to detect the clusters of COVID-19 in mainland China with a different maximum clustering radius at the family-level based on case dates of onset. The results show that the detected clusters vary with the clustering radius. Forty-three space-time clusters were detected with a maximum clustering radius of 100 km and 88 clusters with a maximum clustering radius of 10 km from 2 December 2019 to 20 June 2020. Using a smaller clustering radius may identify finer clusters. Hubei has the most clusters regardless of scale. In addition, most of the clusters were generated in February. That indicates China’s COVID-19 epidemic prevention and control strategy is effective, and they have successfully prevented the virus from spreading from Hubei to other provinces over time. Well-developed provinces or cities, which have larger populations and developed transportation networks, are more likely to generate space-time clusters. The analysis based on the data of cases from onset may detect the start times of clusters seven days earlier than similar research based on diagnosis dates. Our analysis of space-time clustering based on the data of cases on the family-level can be reproduced in other countries that are still seriously affected by the epidemic such as the USA, India, and Brazil, thus providing them with more precise signals of clustering.

An improved version of the Load/Unload Response Ratio method for forecasting strong aftershocks

2011 ◽  
Vol 509 (3-4) ◽  
pp. 191-197 ◽  
Author(s):  
Lang-ping Zhang ◽  
Jiancang Zhuang
Keyword(s):  
Ratio Method ◽  
Response Ratio

Experimental assessment of fractal scale-similarity in turbulent flows. Part 1. One-dimensional intersections

1996 ◽  
Vol 327 ◽  
pp. 35-72 ◽  
Author(s):  
Richard D. Frederiksen ◽  
Werner J. A. Dahm ◽  
David R. Dowling
Keyword(s):  
Turbulent Flows ◽  
Temporal Structure ◽  
Three Dimensional ◽  
Scalar Fields ◽  
Energy Dissipation Rate ◽  
Random Sets ◽  
Scalar Dissipation ◽  
Temporal Scales ◽  
Scale Similarity ◽  
Spatio Temporal

Results are presented from an assessment of the applicability of fractal scale-similarity in the spatio–temporal structure of Sc [Gt ] 1 conserved scalar fields ζ(x, t) and scalar energy dissipation rate fields ∇(x, t) in turbulent flows. Over 2 million spatial and temporal intersections were analysed from fully resolved three-dimensional (256) spatial measurements as well as fully resolved four-dimensional spatio–temporal measurements containing up to 3 million points. Statistical criteria were used to assess both deterministic and stochastic fractal scale-similarity and to differentiate between fractal and random sets. Results span the range of spatio–temporal scales from the scalar diffusion scales (ΛD, TD) to the viscous diffusion scales (Λv, Tv) and to the outer scales (δ, Tδ). Over this entire range of scales, slightly over 99.0% of all intersections with the scalar dissipation support geometry showed scale-similarity as fractal as stochastically self-similar fBm sets having the same record length. Dissipation values above the mean were found to have support dimension D = 0.66. The dissipation support dimension decreased sharply with increasing dissipation values. Virtually no intersections showed scaling as random as a random set with the same relative cover. In contrast, intersections with scalar isosurfaces showed scaling only approximately as fractal as a corresponding fBm set and only over the range of spatio–temporal scales between (ΛD, TD) and (Λv, Tv). On these inner scales the isosurface dimension was D = 0.48 and was largely independent of the isoscalar value. At larger scales, scalar isosurfaces showed no fractal scale-similarity. In contrast, isoscalar level crossing sets showed no fractal scale-similarity over any range of scales, even though the scalar dissipation support geometry for the same data is clearly fractal. These results were found to be unaffected by noise.

scholarly journals Renin- és aldoszteronvizsgálat hypertoniás betegekben

2016 ◽  
Vol 157 (21) ◽  
pp. 830-835
Author(s):  
Tamás Hussein ◽  
Emese Mezősi ◽  
Beáta Bódis ◽  
Orsolya Nemes ◽  
Károly Rucz ◽  
...  
Keyword(s):  
Retrospective Analysis ◽  
Primary Aldosteronism ◽  
Screening Test ◽  
Diagnostic Algorithm ◽  
Ratio Method ◽  
Aldosterone Level ◽  
Hypertensive Patients

Introduction: The diagnostic algorithm of primary aldosteronism is burdened with uncertainties and, recently, it has been suggested that the sensitivity of the aldosterone/renin ratio used as a screening test – based on the suppression aldosterone – is low. Aim: The primary aim was to test the accuracy of aldosterone/renin ratio. Method: In a retrospective analysis of 309 hypertensive patients supine and ambulatory aldosterone levels were independently examined. Results: Aldosterone/renin ratio was elevated in 99 patients of whom 31 exhibited elevated supine aldosterone, as well. In 34 cases supine aldosterone was increased without elevation of the aldosterone/renin ratio. However, only 3 of them had concomitant low renin levels indicating that primary aldosteronism could not be ruled out. Abnormally increased renin was found in 69 patients, but only 59% of them had increased aldosterone level. Conclusion: Sensitivity of aldosterone/renin ratio is high (91%) if used only in justified cases. Orv. Hetil., 2016, 157(21), 830–835.

scholarly journals Adverse reactions to anti-tuberculous drugs in patients with pulmonary tuberculosis and ways to eliminate them

2020 ◽  
pp. 13-16
Author(s):  
M.M. Kuzhko ◽  
V.M. Melnyk ◽  
М.І. Gumeniuk ◽  
T.V. Tlustova ◽  
T.A. Sprynsian
Keyword(s):  
Side Effects ◽  
Pulmonary Tuberculosis ◽  
Retrospective Analysis ◽  
Medical Records ◽  
Adverse Reactions ◽  
Treatment Effectiveness ◽  
Medical Sciences ◽  
Impact On Treatment ◽  
Practical Recommendations

ABSTRACT. Here we present the results of retrospective analysis of medical records of 2292 patients with all forms of pulmonary tuberculosis aged 20 to 65 years, who were treated at the National Institute of Tuberculosis and Pulmonology named after F.G. Yanovsky of National Academy of Medical Sciences of Ukraine in 2000-2018. We analyzed the most common side effects of anti-tuberculous drugs and their impact on treatment effectiveness. Practical recommendations for the elimination of adverse reactions to anti-tuberculous drugs in order to increase the effectiveness of treatment of patients with pulmonary tuberculosis are given here.

scholarly journals SPATIAL DEPENDENCE OF RANDOM SETS AND ITS APPLICATION TO DISPERSION OF BARK BEETLE INFESTATION IN A NATURAL FOREST

2011 ◽  
Vol 30 (3) ◽  
pp. 123 ◽  
Author(s):  
Markus Kautz ◽  
Jochen Düll ◽  
Joachim Ohser
Keyword(s):  
Bark Beetle ◽  
Nearest Neighbor ◽  
Image Interpretation ◽  
Random Sets ◽  
Aerial Image ◽  
Data Set ◽  
Spatially Correlated ◽  
Covariance Functions ◽  
Cross Covariance ◽  
Spatio Temporal

A large spatio-temporal data set monitoring the annual progress of bark beetle infestation in the Bavarian Forest National Park (Germany) is statistically analysed by means of complex image analysis algorithms. The infestation data were obtained by color-infrared (CIR) aerial image interpretation and cover 10 subsequent years (2001–2010). Newly emerged infestation patches are hypothesized as spatially correlated to locations of previous year’s infestation. Both areas, source patches and subsequently emerged patches, are considered as two disjoint random sets. Their spatio-temporal dependence is analysed by two methods: the classical approach based on the measurement of cross-covariance functions, and a second one based on nearest neighbor distances. The resulting characteristics can be interpreted as pre-disposition probabilities of bark beetle infestation depending on distance to sources. Both methods show a strong short-range preference, which decreases with increasing distances.

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