scholarly journals Real-time forecast of MUF for radio paths from current data obtained from oblique sounding with continuous chirp signal

2018 ◽  
Vol 4 (3) ◽  
pp. 83-91
Author(s):  
Николай Ильин ◽  
Nikolay Ilyin ◽  
Татьяна Бубнова ◽  
Tatyana Bubnova ◽  
Виктор Грозов ◽  
...  
Keyword(s):  
Real Time ◽  
Forecast Error ◽  
Current Data ◽  
Transmission Curve ◽  
Term Forecast ◽  
Curve Method ◽  
Using Data ◽  
Time Extrapolation

We present a technique of MUF real-time forecast based on time extrapolation for maximum observed frequencies smoothed over a long-term forecast along a given path. We have validated the technique of fitting current data from the long-term forecast, using the OPEMI model, transmission curve method for short paths, and method of normal waves for long paths (over 2000 km). This technique has been tested using data obtained at the chirp sounding network of ISTP SB RAS during periods of strong and weak solar activity. The quality of the forecast has been found to significantly improve in comparison to the long-term forecast, with advance intervals of real-time forecast from 15 to 30 min. The sessions, in which the real-time forecast error is less than 10 % for 15-min advance interval, comprise from 67 to 96 % of all sessions depending on season and radio path orientation.

scholarly journals Real-time forecast of MUF for radio paths from current data obtained from oblique sounding with continuous chirp signal

2018 ◽  
Vol 4 (3) ◽  
pp. 103-113
Author(s):  
Николай Ильин ◽  
Nikolay Ilyin ◽  
Татьяна Бубнова ◽  
Tatyana Bubnova ◽  
Виктор Грозов ◽  
...  
Keyword(s):  
Real Time ◽  
Forecast Error ◽  
Current Data ◽  
Transmission Curve ◽  
Term Forecast ◽  
Curve Method ◽  
Using Data ◽  
Time Extrapolation

We present a technique of MUF real-time forecast based on time extrapolation for maximum observed frequencies smoothed over a long-term forecast along a given path. We have validated the technique of fitting current data from the long-term forecast, using the OPEMI model, transmission curve method for short paths, and method of normal waves for long paths (over 2000 km). This technique has been tested using data obtained at the chirp sounding network of ISTP SB RAS during periods of strong and weak solar activity. The quality of the forecast has been found to significantly improve in comparison to the long-term forecast, with advance intervals of real-time forecast from 15 to 30 min. The sessions, in which the real-time forecast error is less than 10 % for 15-min advance interval, comprise from 67 to 96 % of all sessions depending on season and radio path orientation.

Pierwotna małopłytkowość immunologiczna u dzieci

2018 ◽  
Vol 22 (4) ◽  
Author(s):  
Anna Dusza ◽  
Michał Matysiak
Keyword(s):  
Immune Thrombocytopenia ◽  
Clinical Symptoms ◽  
Pediatric Population ◽  
Current Data ◽  
Current Investigation ◽  
Surgical Interventions ◽  
Hematological Disorders ◽  
Primary Immune Thrombocytopenia

In this article we present current investigation on primary immune thrombocytopenia in children. There are described pathomorphology, clinical symptoms, diagnosis and treatment. We also present current data from literature about genetic tests and latest data on treating options in children. Primary immune thrombocytopenia (ITP) is one of the most frequent hematological disorders in pediatric population. Although the majority of children have a self-limited and short duration of the disease. However, approximately 20-30% of those patients can develop chronic ITP, which can cause significant complications and higher mortality and reduced quality of life. Especially regarding to long-term immunosupression or surgical interventions, such like splenectomy and restrictions on daily activities to avoid trauma. Over the past decades a lot of informations has been reported about pathogenic features of ITP. Nowdays, we know that it is not only caused by increased platet destruction and decreased platet production, but also complex, multifactorial immune dysregulation, like loss of immune tolerance and generation of platelet autoantibodies. In this article we present current investigation on ITP including clinical symptoms, diagnosis, pathomorphology and latests options on treatment in children. We also present current data about genetic biomarker, such as Vanin-1 (VNN-1) which has been suggested as one of predictors of chronic disease and potentially can offer early prognosis estimation.

scholarly journals SOIL MANAGEMENT IN THE URBAN ENVIRONMENT: TODAY AND FUTURE

2019 ◽  
Vol 1 (1) ◽  
pp. 66-71
Author(s):  
Bogdan Stanescu ◽  
Adriana Cuciureanu
Keyword(s):  
Performance Management ◽  
Urban Environment ◽  
Urban Areas ◽  
Large Scale ◽  
Current Data ◽  
Soil Protection ◽  
The European Union ◽  
Residential Areas

The present article presents the expertise realized by the Department of Environmental Monitoring Pollution Evaluation within the INCD ECOIND, in the evaluation of the quality of urban soils in the municipality of Bucharest and the main big cities in Romania. The current data available at the level of the 27 member states of the European Union show that annually over 100,000 hectares of land are introduced into the urban environment, a direct consequence of the development of cities. There are a number of legislative obstacles to strategic soil protection measures. Moreover, at the level of the local authorities there is a conflict regarding the measures of soil protection in the long term, on the one hand, and, the accelerated economic development in the short term, on the other. European environmental experts consider that the urban development, absolutely necessary for the economic growth, requires an adequate management of the natural resources in order for the development to be done on a sustainable basis, respectively to follow a series of strategic objectives. In our country, at least in the last decade, we find on a large scale the conversion of industrial areas into commercial or residential areas. The footprint of industrial activities can be found even after long periods of time present by identifying the remnant of soil pollution or in those areas known as historically polluted (for example the town of Copsa Mica). The conclusions stemming from the assessment of pollution in urban areas over large areas, in correlation with the potential sources of pollution, underline the need to monitor the quality of soils in the urban environment, but also to apply a performance management in order to protect this natural resource in the long term.

USE OF REGRESSION ANALYSIS IN FORECAST TASKS

2020 ◽  
pp. 22-27
Author(s):  
E.S. Lartseva ◽  
◽  
A.D. Kuznetsova
Keyword(s):  
Regression Analysis ◽  
Animal Population ◽  
Short Term ◽  
Statistical Estimates ◽  
Term Forecast ◽  
Applied Software ◽  
The Family ◽  
The Russian Federation

Based on official statistics on the number, of representatives of the family of non-ruminant cloven-hoofed animals (Artiodactyl) on the territory of the Russian Federation. Using the example of two species: domestic pigs and wild boars, the dynamics of the indicator for the long term is analyzed. Multidirectional trends were revealed for each species. Mathematical models of the dynamics of the livestock were obtained using the methods of regression analysis and applied software. Statistical estimates of the quality of animal population models were obtained. The short-term forecast for 2020 has been fulfilled.

Pregabalin and Fibromyalgia Syndrome: A Treatment Option

2009 ◽  
Vol 1 ◽  
pp. CMT.S1094
Author(s):  
Kim Lawson
Keyword(s):  
Patient Population ◽  
Multidisciplinary Approach ◽  
Care Setting ◽  
Clinical Trial Design ◽  
Current Data ◽  
Assessment Tools ◽  
Positive Outcomes ◽  
Double Blind

Fibromyalgia (FM) is a chronic complex pain disorder that is multidimensional and exhibits heterogeneity requiring a long-term multidisciplinary approach to management. Many of the drugs used in the treatment of FM have been focused to the management of single symptoms; often such drugs fail to demonstrate acceptable efficacy in the majority of the patient population. Pregabalin is an α2-δ ligand that regulates the release and postsynaptic actions of neurotransmitters related to analgesic, anticonvulsant and anxiolytic properties. In randomized, double-blind, placebo-controlled studies, pregabalin has demonstrated an improvement in pain, sleep and fatigue symptoms associated with FM, as well as offering an improvement in parameters related to quality of life. Although the positive outcomes obtained with pregabalin support its use as an option for the management of FM, the efficacy was restricted to a selected patient population outside of the usual care setting. Current data do not allow an explanation where there are any limitations of pregabalin as a treatment of patients with FM, as to whether this is a deficiency of the drug or the process of assessment (e.g. assessment tools of FM, clinical trial design).

A Triangle Matching Algorithm for Gravity-aided Navigation for Underwater Vehicles

2013 ◽  
Vol 67 (2) ◽  
pp. 227-247 ◽  
Author(s):  
Zhenli Yang ◽  
Zhuangsheng Zhu ◽  
Weigao Zhao
Keyword(s):  
Real Time ◽  
Navigation Systems ◽  
Inertial Navigation Systems ◽  
Matching Algorithm ◽  
Initial Errors ◽  
Local Gravity ◽  
Gravity Measurements ◽  
Using Data ◽  
Real Time Simulations

In this paper, a triangle matching algorithm using local gravity field maps is proposed to bound the drift errors inherent in Strapdown Inertial Navigation Systems (SINS) in gravity-aided navigation. This triangle matching algorithm has two main stages, the first is the initial matching stage, which has a coarse phase and a fine phase to address the large unknown initial errors made by INS, and the other is the tracking matching stage, which mainly aims at tracking the matching solution with the vehicle running in real time. Simulations were carried out using data for the Bohai Sea and South China Sea areas, to assess the effects of different initial errors on the matching solutions. Finally some experiments were carried out to evaluate the proposed algorithm. The results show that the triangle matching algorithm has some compelling advantages, such as a capability to address the large unknown initial errors made by INS, and good real-time quality of matching the gravity measurements with the local gravity maps.

Using STEREO-HI beacon data to predict CME arrival time and speed with the ELEvoHI model

2020 ◽  
Author(s):  
Maike Bauer ◽  
Tanja Amerstorfer ◽  
Jürgen Hinterreiter ◽  
Christian Möstl ◽  
Jackie A. Davies ◽  
...  
Keyword(s):  
Real Time ◽  
Coronal Mass Ejections ◽  
Arrival Time ◽  
Geomagnetic Storms ◽  
Leading Edge ◽  
Science Data ◽  
Electrical Devices ◽  
Using Data ◽  
Heliospheric Imager

<div> <div> <div> <div> <p>Coronal mass ejections (CMEs) may induce strong geomagnetic storms which have a significant impact on satellites in orbit as well as electrical devices on Earth’s surface. If we want to be able to mitigate the potentially devastating consequences which strong CMEs might have on Earth, developing models which accurately predict their arrival time is an integral step. The Ellipse Evolution model based on Heliospheric Imager observations (ELEvoHl) predicts the arrival of coronal mass ejections using data from STEREO’s HI instruments. HI data is available as high-resolution science data, which is downlinked every few days and low-resolution beacon data, which is downlinked in near real-time. Therefore, to allow for real time predictions of CME arrivals, beacon data must be used. We study different data reduction procedures to improve the quality of the measurements and compile the resulting images into time-elongation plots (J-plots). We track the leading edge of each selected CME event by hand, resulting in a series of time-elongation points which function as input for the ELEvoHI model. We compare the resulting predictions to those obtained using science data in terms of accuracy and errors of the predicted arrival time and speed.</p> </div> </div> </div> </div>

scholarly journals On the uncertainty of real-time predictions of epidemic growths: A COVID-19 case study for China and Italy

2021 ◽  
Author(s):  
Tommaso Alberti ◽  
Davide Faranda
Keyword(s):  
Real Time ◽  
Asymptotic Distributions ◽  
Quality Of Data ◽  
Asymptomatic Patients ◽  
Italian Regions ◽  
Extreme Care ◽  
Linear Nature

<p>While COVID-19 is rapidly propagating around the globe, the need for providing real-time forecasts of the epidemics pushes fits of dynamical and statistical models to available data beyond their capabilities. Here we focus on statistical predictions of COVID-19 infections performed by fitting asymptotic distributions to actual data. By taking as a case-study the epidemic evolution of total COVID-19 infections in Chinese provinces and Italian regions, we find that predictions are characterized by large uncertainties at the early stages of the epidemic growth. Those uncertainties significantly reduce after the epidemics peak is reached. Differences in the uncertainty of the forecasts at a regional level can be used to highlight the delay in the spread of the virus. Our results warn that long term extrapolation of epidemics counts must be handled with extreme care as they crucially depend not only on the quality of data, but also on the stage of the epidemics, due to the intrinsically non-linear nature of the underlying dynamics. These results suggest that real-time epidemiological projections should include wide uncertainty ranges and urge for the needs of compiling high-quality datasets of infections counts, including asymptomatic patients.</p><p>Alberti T. and Faranda D. (2020) <span>On the uncertainty of real-time predictions of epidemic growths: A COVID-19 case study for China and Italy. <em>Commun. Nonlin. Sci. Num. Sim.</em>, <strong>90</strong>, 105372.</span></p>

Studying changes in climate normals in long-term forecasting of the Sea of Okhotsk ice cover.

2021 ◽  
Vol 3 ◽  
pp. 99-114
Author(s):  
G.I. Anzhina ◽  
◽  
A.N Vrazhkin ◽  
Keyword(s):  
Statistical Model ◽  
Quantitative Difference ◽  
Ice Cover ◽  
Absolute Maximum ◽  
Base Period ◽  
Term Forecast ◽  
Skill Scores ◽  
Long Term Forecasting

There is a similarity in dynamics and a quantitative difference in the ice cover regime in four consecutive 30-year periods: 1961–1990, 1971–2000, 1981–2010, 1991–2020 are noted. The greatest differences are observed in the regime characteristics of the first and the last periods. The absolute maximum or minimum recorded in at least one of the months from January to May determines the nature of the ice cover of the entire ice season. The sensitivity of the predictive physical-statistical model to the replacement of climatic norms has been investigated. Estimates of the quality of forecasts of the average monthly ice cover are obtained. Keywords: base period, long-term forecast, physical and statistical model, ice cover, climate characteristics, typification, forecast skill scores

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