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under the background of climate warming, obvious decrease trend in frequency and intensity of cold wave that invaded Guangdong province, South China have been observed in recent years. However in January of 2016, a named “super cold wave” which caused serious influence on human health and agriculture production invaded Guangdong. In this paper, satellite derived land surface temperature (LST) from...
Land use and land cover (LULC) change monitoring is still an important remote sensing application and research field, for it is closely related to manage natural resources and environmental planning. This study is aimed to find the land use and land cover changes of Zigui County from 2008 to 2014 by using multi-source remotely sensed imagery. Images of three different years (2008, 2011 and 2014) taken...
Reliability of a navigation system is one of greatimportance for navigation purposes. Therefore, anintegrity monitoring system is an inseparable part of aviation navigation system. Failures or faults due to malfunctions in the systems should be detected and repaired to keep the integrity of the system intact. In this paper, we present a method based on wavelet analysis for detecting failures. The...
Biomass burning is one of the main atmospheric aerosol sources in South America, which can increase human mortality due to respiratory and cardiovascular disorders. Thus, atmospheric pollutants monitoring is important, mainly in cities where daily anthropogenic emissions are considerable and can receive pollution from frequent environmental events (e.g. forest fires and soil erosion). Even when air...
Location systems have known a very large scale spreading and developing in the last period, being known mainly through the navigation applications which ensure route guidance accordingly to the current position. This development was made possible by combining different localization modes (GPS, GLONASS, GPS-A etc.), which conduced to the precision required for developing a large number of specific...
The aim of this paper is to propose a complementary Health Management module to monitor the GPS accuracy for autonomous vehicles. Based on sensor information, the error causes of GPS can be observed in some specific contexts (urban, climate…). The proposed module relies on a Bayesian Network model that allows to reinforce the belief of GPS failure based on evidence. A hardware/software implementation...
The ground monitoring of an active volcanic area presents many complexities. By exploiting the remote sensing techniques, we developed an analytical methodology for observing and quantifying eruptive processes and the related phenomena (lava flows, volcanic avalanche/landslides, slope stability features). This methodology integrates HR optical images and SAR interferometry, acquired in different time...
On the basis of the coherent concept a decomposition of the polarimetric scattering matrix of a radar remote sensing object is performed. With the usage of the complex numbers mathematics a scattering operator that compactly describes transformation of the backscattered signal polarization is received. The expressions for invariant polarization transfer functions that separately describe transformations...
Continuous monitoring of coastal areas is a necessary condition for proper coastal activities regulation. Coastal area alterations, even in the short term, in fact, may lead to a significant social change in the development of economic activities and lifestyle in populations living in coastal regions. This paper deals with the development of an integrated operational Earth Observation system aimed...
Positioning errors of stand-alone GNSS can be reduced with different real-time augmentation approaches. For many navigation and positioning applications, Satellite-Based Augmentation System (SBAS) and Differential code-based GNSS (DGNSS) can offer substantial improvement in the positioning accuracy. Finland is covered by EGNOS (European Geostationary Overlay Service) even though it is lying at the...
In this paper, we get through some work to solve a detailed problem of the cesium active optical clock. With 459 nm laser pumping, the exact hyperfine energy levels between which the stimulated emission of Cs active optical clock takes place are studied.
For safety-of-life applications, such as landing an aircraft, the detection of ionospheric gradients is important both for the integrity of single frequency GBAS users as the availability for dual frequency users. In this paper an ionospheric gradient monitor is proposed, based on carrier phase observations. Carrier phase observations are very precise, but ambiguous. Although in aviation carrier phase...
Due to a rapid development of several Global Navigation Satellite Systems (GNSS), multiple constellations are available to enhance navigation performance and safety. With the growing number of satellite constellations, the task of the GNSS navigation is to deal with the differences among systems but, on the other hand, more great levels of integrity and satellite visibility can be expected. GNSS navigation...
For years, Virtual Network Operators (VNOs) are a major player in the satellite communication market landscape. Typically, they repackage services leased from Satellite Network Operators (SNOs) to provide their customers with added-value end-to-end services that mostly go beyond the satellite network and cover terrestrial networks. However, the level of control and visibility that VNOs have on their...
As one possible continuation of development of Masat-1, the first Hungarian satellite, in 2015, a group of student, from Faculty of Electrical Engineering and Informatics and Mechanical Engineering, decided to realize a PocketQube-class satellite, called Smog-1. Smog-1 is a 5 cm cubesat as PocketQube with less than 180 g mass. The aim of Smog-1 is to measure the radio frequency (RF) smog caused by...
RST was involved in studies on a Geosynchron-ous SAR for daily monitoring of large areas. In this study the feasibility of such a system was verified. The SAR is designed to cover the entire Mediterranean Sea once per day. The spatial resolution is with about 20m high enough in order to detect even small boats because the contrast between boats and ocean surface is typically strong enough. The design...
Gautala Autramghat Wildlife Sanctuary is a protected forest area of Aurangabad, Maharashtra state, India. It lies in the Ajanta hill ranges of the Western Ghats; it is administrated by Forest Authority of Aurangabad and Jargon District. In 1986, it was established as the wildlife sanctuary in an existing forest area. The forest area is southern tropical dry deciduous forest, with interspersed shrubs...
Two critical parameters for Advanced Receiver Autonomous Integrity Monitoring (ARAIM) are the probability of satellite fault, Psat, and the probability of constellation fault, Pconst. A satellite fault is one whose root cause is only capable of affecting a single satellite; while a constellation fault has a root cause that is capable of affecting more than one satellite at the same time. This paper...
The following case study describes how a series of operational concept demonstrations provided significant benefits for the OCX program and how the lessons learned from that experience can be applied to other large, complex programs with multiple stakeholders.
In recent years GNSS has become the recognised core element for the provision of accurate and reliable positioning, velocity and timing (PVT) data for multiple navigational applications. However, since the occurrence of strong ionospheric disturbances impacts the accuracy of GNSS measurements leading consequently to unreliable PVT solutions, not only precision and accuracy but also high-level reliability...
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