554 research outputs found
Failure Detection of a Pseudolite-Based Reference System Using Residual Monitoring
The 746th TS uses a flight reference system referred to as the Central Inertial and GPS Test Facility (CIGTF) Reference System (CRS). Currently the CRS is the modern standard flight reference system for navigation testing, but high accuracy is dependent on the availability of GPS. A pseudolite system is currently being developed to augment the CRS and supply the capability to maintain high accuracy navigation under normal and jamming conditions. Pseudolite measurements typically contain cycle slips and other errors (such as multipath, tropospheric error, measurement noise) that can affect reliability. Past work relied on the receiver-reported signal-to-noise (SNR) value to determine whether or not a cycle slip occurred. However it has been shown that even when the SNR is relatively high, a cycle clip can occur. To reduce the error in the pseudolite measurements, the pseudolite system was integrated with an inertial navigation sys- tem (INS). The integrated system detects failures through residual monitoring using a likelihood function. Integrating the inertial sensor provides a means for a filter to maintain the reliability of the pseudolite data which, in turn, increases the integrity of the resulting navigation solution. An experiment was conducted using six pseudolites and a ground vehicle equipped with a pseudolite receiver, and both a commercial-grade and tactical-grade inertial systems. The inertial data was combined with both real and simulated data to evaluate cycle slip detection performance. Results from this experiment have shown cycle slips in the carrier phase measurements were detected and corrected using both commercial-grade and tactical- grade INS, but that performance, in terms of probability of detection and time to detect, was improved with the higher quality inertial data
Application of HR-NMR for the Metabolic Kinetic Assessment of Red Mullet (Mullus barbatus) and Bogue (Boops boops) Samples during Different Temperature Storage
: Fish freshness and quality can be measured through several indices that can be both chemical and physical. The storage temperature and the time that elapses following the catching of the fish are fundamental parameters that define and influence both the degree of freshness and nutritional quality. Moreover, they particularly effect the kind of fish we considered. In this research, it was observed how different temperatures of storage and shelf-life (+4 °C and 0 °C) may affect the metabolic profile of red mullet (Mullus barbatus) and bogue (Boops boops) fish samples over time, specifically observing the alteration of freshness and quality. In particular, a High-Resolution Nuclear Magnetic Resonance (HR-NMR)-based metabolomics approach was applied to study the metabolic profile changes that occur in fish spoilage. The HR-NMR spectroscopy data were useful for calculating a kinetic model that was able to predict the evolution of different compounds related to fish freshness, such as trimethylamine (TMA-N) and adenosine-5'-triphosphate (ATP) catabolites for the K-index. Furthermore, NMR in combination with chemometrics allowed us to estimate a further kinetic model able to represent the spoilage evolution by considering the entire metabolome. In this way, it was also possible to detect further biomarkers characterizing the freshness and quality status of both red mullets and bogues
People v. Keta: The Search for Stolen Auto Parts--Warrantless Searches of Chop Shops in New York
An evaluation of a group of exercises in reading prepared for slow learning children in the primary grades
Thesis (M.Ed.)--Boston Universit
Validation of a 1H-NMR Spectroscopy Quantitative Method to Quantify Trimethylamine Content and K -Index Value in Different Species of Fish
The chemical analysis that is frequently employed for the evaluation of the freshness of fish includes (i) the quantification of trimethylamine (TMA) and (ii) the estimation of the K-Index, based on the ratio between the concentrations of adenosine triphosphate (ATP) and its breakdown products. TMA is quantified using a colorimetric reference method (AOAC), while the K-Index is usually determined by HPLC. The present work proposes a method for the above freshness biomarkers based on HR H-1-NMR as an alternative method able to assess both indexes simultaneously on aqueous fish extracts. To validate the proposed H-1-NMR method, a large set of validation checks has been addressed, such as accuracy, precision, specificity, limits of detection, linearity, and range of linearity and quantification according to EuroChem guidelines. The results show that the methodology satisfies all the validation requirements at the same level as the most frequently used methods, with the advantage of being faster and more repeatable, avoiding the use of solvents, such as toluene and formaldehyde, or dangerous reagents such as picric acid
Study on ultra-structural effects caused by Onion yellow dwarf virus infection in ‘Rossa di Tropea’ onion bulb by means of magnetic resonance imaging
\u2018Rossa di Tropea\u2019 onion is a particular pink/red coloured onion cultivated in Calabria region (Southern Italy), representing one of the Italian most important vegetable crops granted with Protected Designation of Origin (PDO) and Protected Geographical Indication (PGI) trademarks. This local cultivar is characterised by a high nutraceutical compounds content showing anti-inflammatory, anti-cholesterol, anticancer and antioxidant properties. As all vegetable crops and Allium spp., \u2018Rossa di Tropea\u2019 onion is affected by several viruses. Among these, the species Onion yellow dwarf virus (OYDV, genus Potyvirus, family Potyviridae), represents the most limiting biotic stress, inducing severe symptoms. OYDV effect on tissues architecture in whole bulbs was investigated using magnetic resonance microimaging (MRI) technique, which allows the interior of samples to be imaged non-invasively and non-destructively and yields quantitative information on physico-chemical parameters describing water mobility (T1 and T2 relaxation times). The use of such tool allowed to determine how OYDV alters plant physiology by inducing water accumulation in bulb tissues as well as causing ultra-structural modifications of cell wall, highlighted by MRI. All these effects resulted in an increase of free water in plant tissues, and consequently relevant water losses during post-harvest storage, seriously affecting bulb quality, marketability and shelf life
Gamification techniques for raising cyber security awareness
Due to the prevalence of online services in modern society, such as internet banking and social media, it is important for users to have an understanding of basic security measures in order to keep themselves safe online. However, users often do not know how to make their online interactions secure, which demonstrates an educational need in this area. Gamification has grown in popularity in recent years and has been used to teach people about a range of subjects. This paper presents an exploratory study investigating the use of gamification techniques to educate average users about password security, with the aim of raising overall security awareness. To explore the impact of such techniques, a role-playing quiz application (RPG) was developed for the Android platform to educate users about password security. Results gained from the work highlightedthat users enjoyed learning via the use of the password application, and felt they benefitted from the inclusion of gamification techniques. Future work seeks to expand the prototype into a full solution, covering a range of security awareness issues
Epigallocatechine-3-gallate reduces allergen-induced asthma-like reaction in sensitised guinea pigs.
Recommended from our members
Experimental Results of Neutron Fluence Outside an Iron Shield in the Forward Direction
This work represents the first systematic study at a high energy accelerator of the depth dependence of neutron fluence in longitudinal shielding
- …