scholarly journals Spatio-Temporal Focusing for Elimination of Multipath Effects in High Rate Acoustic Communications

2004 ◽  
Author(s):  
Milica Stojanovic
Keyword(s):  
High Rate ◽  
Acoustic Communications ◽  
Temporal Focusing ◽  
Multipath Effects ◽  
Spatio Temporal

scholarly journals Spatio-temporal epidemiology of the tuberculosis incidence rate in Iran 2008 to 2018

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Behzad Kiani ◽  
Amene Raouf Rahmati ◽  
Robert Bergquist ◽  
Soheil Hashtarkhani ◽  
Neda Firouraghi ◽  
...  
Keyword(s):  
High Risk ◽  
Incidence Rate ◽  
Policy Development ◽  
Temporal Pattern ◽  
Temporal Analysis ◽  
High Rate ◽  
Spatial Scan Statistic ◽  
Cross Sectional ◽  
Risk Areas ◽  
Spatio Temporal

Abstract Background Effective reduction of tuberculosis (TB) requires information on the distribution of TB incidence rate across time and location. This study aims to identify the spatio-temporal pattern of TB incidence rate in Iran between 2008 and 2018. Methods This cross-sectional study was conducted on aggregated TB data (50,500 patients) at the provincial level provided by the Ministry of Health in Iran between 2008 and 2018. The Anselin Local Moran’s I and Getis-Ord Gi* were performed to identify the spatial variations of the disease. Furthermore, spatial scan statistic was employed for purely temporal and spatio-temporal analyses. In all instances, the null hypothesis of no clusters was rejected at p ≤ 0.05. Results The overall incidence rate of TB decreased from 13.46 per 100,000 (95% CI: 13.19–13.73) in 2008 to 10.88 per 100,000 (95% CI: 10.65–11.11) in 2018. The highest incidence rate of TB was observed in southeast and northeast of Iran for the whole study period. Additionally, spatial cluster analysis discovered Khuzestan Province, in the West of the country, having significantly higher rates than neighbouring provinces in terms of both total TB and smear-positive pulmonary TB (SPPTB). Purely temporal analysis showed that high-rate and low-rate clusters were predominantly distributed in the time periods 2010–2014 and 2017–2018. Spatio-temporal results showed that the statistically significant clusters were mainly distributed from centre to the east during the study period. Some high-trend TB and SPPTB statistically significant clusters were found. Conclusion The results provided an overview of the latest TB spatio-temporal status In Iran and identified decreasing trends of TB in the 2008–2018 period. Despite the decreasing incidence rate, there is still need for screening, and targeting of preventive interventions, especially in high-risk areas. Knowledge of the spatio-temporal pattern of TB can be useful for policy development as the information regarding the high-risk areas would contribute to the selection of areas needed to be targeted for the expansion of health facilities.

scholarly journals Adaptive optics with spatio-temporal lock-in detection for temporal focusing microscopy

2021 ◽  
Author(s):  
Keisuke Isobe ◽  
Tomohiro Ishikawa ◽  
Kenta Inazawa ◽  
KANA NAMIKI ◽  
Atsushi Miyawaki ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Temporal Focusing ◽  
Spatio Temporal ◽  
Lock In

scholarly journals High-rate wireless data communications: An underwater acoustic communications framework at the physical layer

1996 ◽  
Vol 2 (6) ◽  
pp. 449-485 ◽  
Author(s):  
Anthony G. Bessios ◽  
Frank M. Caimi
Keyword(s):  
Real Time ◽  
High Speed ◽  
High Rate ◽  
Statistical Decision Theory ◽  
Data Communications ◽  
Acoustic Communications ◽  
Statistical Decision ◽  
Theoretical Formulation ◽  
Underwater Acoustic ◽  
Detection Techniques

A variety of signal processing functions are performed by Underwater Acoustic Systems. These include: 1) detection to determine presence or absence of information signals in the presence of noise, or an attempt to describe which of a predetermined finite set of possible messages{mi,i,...,M}the signal represents; 2) estimation of some parameterθˆassociated with the received signal (i.e. range, depth, bearing angle, etc.); 3) classification and source identification; 4) dynamics tracking; 5) navigation (collision avoidance and terminal guidance); 6) countermeasures; and 7) communications. The focus of this paper is acoustic communications.There is a global current need to develop reliable wireless digital communications for the underwater environment, with sufficient performance and efficiency to substitute for costly wired systems. One possible goal is a wireless system implementation that insures underwater terminal mobility. There is also a vital need to improve the performance of the existing systems in terms of data-rate, noise immunity, operational range, and power consumption, since, in practice, portable high-speed, long range, compact, low-power systems are desired.We concede the difficulties associated with acoustic systems and concentrate on the development of robust data transmission methods anticipating the eventual need for real time or near real time video transmission. An overview of the various detection techniques and the general statistical digital communication problem is given based on a statistical decision theory framework. The theoretical formulation of the underwater acoustic data communications problem includes modeling of the stochastic channel to incorporate a variety of impairments and environmental uncertainties, and proposal of new compensation strategies for an efficient and robust receiver design.

Kerr Spatio-Temporal Focusing in a Planar Glass Waveguide

1999 ◽  
Author(s):  
Hagai Eisenberg ◽  
Roberto Morandotti ◽  
Yaron Silberberg ◽  
Orit Potashnik ◽  
Shimshon Bar-Ad ◽  
...  
Keyword(s):  
Temporal Focusing ◽  
Spatio Temporal ◽  
Glass Waveguide

scholarly journals Spatio-Temporal Analysis of Urban Crime Pattern and its Implication for Abuja Municipal Area Council, Nigeria

2017 ◽  
Vol 49 (2) ◽  
pp. 145
Author(s):  
Taiye Oluwafemi Adewuyi ◽  
Patrick Ali Eneji ◽  
Anthonia Silas Baduku ◽  
Emmanuel Ajayi Olofin
Keyword(s):  
Information System ◽  
Spatial Data ◽  
Temporal Analysis ◽  
Urban Crime ◽  
High Rate ◽  
Geographical Information ◽  
Positioning Systems ◽  
Spatio Temporal ◽  
Gis Environment ◽  
Crime Pattern

This study examined the spatio-temporal analysis of urban crime pattern and its implication for Abuja Municipal Area Council of the Federal Capital Territory of Nigeria; it has the aim of using Geographical Information System to improve criminal justice system. The aim was achieved by establishing crime incident spots, types of crime committed, the time it occurred and factors responsible for prevailing crime. The methods for data collection involved Geoinformatics through the use of remote sensing and Global Positioning Systems (GPS) for spatial data. Questionnaires were administered for other attribute information required. The analysis carried out in a Geographic Information System (GIS) environment especially for mapping and the establishment of spatial patterns.  The results indicated that the main types of crime committed were theft and house breaking (42.9%), followed by assault (12.4%), mischief (11.3%), forgery (10.5%), car snatching (9.05%), armed robbery (8.5%), trespass (5.2%) and culpable homicide (0.2%). In terms of hot spots the districts recorded the following: Garki (27.62%), Maitama (25.7%), Utako (24.3%), Wuse (20.9%) and Asokoro district (1.4%) respectively with most of the crime committed during the day time. Many attributed the crimes to mainly high rate of unemployment and poverty (79.1%). Consequently to reduce the crime rate, the socio-economic situation of the city must be improved through properly constructed interventions scheme in areas known to quickly generate employment such as agriculture, small and medium scale enterprises, mining and tourism. 

scholarly journals Determining spatio-temporal characteristics of coseismic travelling ionospheric disturbances (CTID) in near real-time

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Boris Maletckii ◽  
Elvira Astafyeva
Keyword(s):  
Real Time ◽  
Tohoku Earthquake ◽  
Propagation Speed ◽  
High Rate ◽  
Ionospheric Disturbances ◽  
Temporal Characteristics ◽  
Travelling Ionospheric Disturbances ◽  
Spatio Temporal ◽  
Gnss Data ◽  
First Time

AbstractEarthquakes are known to generate ionospheric disturbances that are commonly referred to as co-seismic travelling ionospheric disturbances (CTID). In this work, for the first time, we present a novel method that enables to automatically detect CTID in ionospheric GNSS-data, and to determine their spatio-temporal characteristics (velocity and azimuth of propagation) in near-real time (NRT), i.e., less than 15 min after an earthquake. The obtained instantaneous velocities allow us to understand the evolution of CTID and to estimate the location of the CTID source in NRT. Furthermore, also for the first time, we developed a concept of real-time travel-time diagrams that aid to verify the correlation with the source and to estimate additionally the propagation speed of the observed CTID. We apply our methods to the Mw7.4 Sanriku earthquake of 09/03/2011 and the Mw9.0 Tohoku earthquake of 11/03/2011, and we make a NRT analysis of the dynamics of CTID driven by these seismic events. We show that the best results are achieved with high-rate 1 Hz data. While the first tests are made on CTID, our method is also applicable for detection and determining of spatio-temporal characteristics of other travelling ionospheric disturbances that often occur in the ionosphere driven by many geophysical phenomena.

scholarly journals Spatio-temporal outbreaks of campylobacteriosis and the role of fresh-milk vending machines in the Czech Republic: A methodological study

2017 ◽  
Author(s):  
Lukáš Marek ◽  
Vít Pászto
Keyword(s):  
Czech Republic ◽  
Raw Milk ◽  
Public Health Research ◽  
High Rate ◽  
The Czech Republic ◽  
Vending Machines ◽  
Fresh Milk ◽  
Potential Link ◽  
Spatial Method ◽  
Spatio Temporal

Inspired by local outbreaks of campylobacteriosis in the Czech Republic in 2010 linked to the debate about alleged health risks of the raw milk consumption, a detailed study was carried out. Firstly, scanning was utilised to identify spatio-temporal clusters of the disease from 2008 to 2012. Then a spatial method (geographical profiling originally developed for criminology) served as assessment in selecting fresh-milk vending machines that could have contributed to some of the local campylobacteriosis outbreaks. Even though an area of increased relative risk of the disease was identified in the affected city of České Budějovice during January and February 2010, geoprofiling did not identify any vending machines in the area as the potential source. However, possible sources in some nearby cities were suggested. Overall, 14 high-rate clusters including the localisation of 9% of the vending machines installed in the Czech Republic were found in the period 2008-2012. Although the vending machines are subject to strict hygiene standards and regular testing, a potential link between a small number of them and the spatial distribution of campylobacteriosis has been detected in the Czech Republic. This should be taken into account in public health research of the disease.

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