Foucault precession manifested in a simple system

This article aims to answer the question, "What is the simplest system that embodies the essence of Foucault's pendulum?" We study a very elementary idealized system that exhibits a precession behavior analogous to the classic pendulum. The system consists of a particle without inertial mass, constrained to an inclined plane that rotates about a vertical axis. Insights gained from this analysis are used to understand the rate of precession in a straightforward way

Peripheral Ossifying Fibroma

Peripheral ossifying fibroma is a relatively uncommon gingival growth that is considered to be reactive in nature and postulated to appear secondary to irritation or trauma. They usually occur in young adults with a female predominance and are solitary in nature. We report a case of peripheral ossifying fibroma in a 55-year old femal

Block Outlier Methods for Malicious User Detection in Cooperative Spectrum Sensing

Block outlier detection methods, based on Tietjen-Moore (TM) and Shapiro-Wilk (SW) tests, are proposed to detect and suppress spectrum sensing data falsification (SSDF) attacks by malicious users in cooperative spectrum sensing. First, we consider basic and statistical SSDF attacks, where the malicious users attack independently. Then we propose a new SSDF attack, which involves cooperation among malicious users by masking. In practice, the number of malicious users is unknown. Thus, it is necessary to estimate the number of malicious users, which is found using clustering and largest gap method. However, we show using Monte Carlo simulations that, these methods fail to estimate the exact number of malicious users when they cooperate. To overcome this, we propose a modified largest gap method.Comment: Accepted in Proceedings of 79th IEEE Vehicular Technology Conference-Spring (VTC-Spring), May 2014, Seoul, South Kore

Hydrogen production from glucose by inhibiting hydrogenotrophic methanogens carbon-18 long-chain fatty acids.

Dark fermentation is an attractive process for hydrogen (H2) production from organic substrates. Rapid conversion of H2 to other products, particularly methane, is a major hindrance to H2 accumulation and recovery from the process. Long chain fatty acids (LCFAs) namely oleic (C18:0) acid (OA) and linoleic (C18:1) acid are inhibitors of aceticlastic methanogens and are suspected inhibitors of hydrogenotrophic methanogens. However, the effect of such inhibition on increasing H2 recovery from organic substrates has not been examined. Hence, in this study, C18 LCFAs were used to increase the quantity of H2 from glucose degradation. Batch experiments were conducted at 23 +/- 2°C to examine the effect of LCFA concentration (0 to 2,000 mg 1-1) and the initial pH (pH 5, 6 and 7.8) on the fermentative H2 production. Glucose was re-injected on day 4 or day 5 to examine the combined effect of LCFA, volatile fatty acids (VFAs) and intermittent sparging on H2 production. H2 production was a function of LCFA concentration and the initial pH. The maximum H2 yield recorded was approximately 2.7 mol H2·mol-1 glucose in cultures receiving LA at an initial pH of 6. Glucose degradation was inhibited in cultures receiving LCFA. Inhibition of glucose degradation was enhanced at lower initial pH values. Overall, the data demonstrated that LA and OA can be used to enhance H 2 accumulation and recovery from organic substrates.Dept. of Civil and Environmental Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .G87. Source: Masters Abstracts International, Volume: 44-03, page: 1472. Thesis (M.A.Sc.)--University of Windsor (Canada), 2005

Long term Ultra-Violet Variability of Seyfert galaxies

Flux variability is one of the defining characteristics of Seyfert galaxies, a class of active galactic nuclei (AGN). Though these variations are observed over a wide range of wavelengths, results on their flux variability characteristics in the ultra-violet (UV) band are very limited. We present here the long term UV flux variability characteristics of a sample of fourteen Seyfert galaxies using data from the International Ultraviolet Explorer acquired between 1978 and 1995. We found that all the sources showed flux variations with no statistically significant difference in the amplitude of UV flux variation between shorter and longer wavelengths. Also, the flux variations between different near-UV (NUV, 1850 - 3300 A) and far-UV (FUV, 1150 - 2000 A) passbands in the rest frames of the objects are correlated with no time lag. The data show indications of (i) a mild negative correlation of UV variability with bolometric luminosity and (ii) weak positive correlation between UV variability and black hole mass. At FUV, about 50% of the sources show a strong correlation between spectral indices and flux variations with a hardening when brightening behaviour, while for the remaining sources the correlation is moderate. In NUV, the sources do show a harder when brighter trend, however, the correlation is either weak or moderate.Comment: Accepted by Journal of Astrophysics and Astronom

Window Expressions for Stream Data Processing

Traditional ways of storing and querying data do not work well in scenarios where data is being generated continuously and quick decisions need to be taken. For example, in hospital intensive care units, signals from multiple devices need to be monitored and the occurrence of any anomaly should raise alarms immediately. A typical design would take the average from a window of say 10 seconds (time-based) or 10 successive (count-based) readings and look for sudden deviations. Existing stream processing systems either restrict the windows to time or count-based windows or let users define customized windows in imperative programming languages. These are subject to the implementers' interpretation of what is desired and hard to understand for others. We introduce a formalism for specifying windows based on Monadic Second Order logic. It offers several advantages over ad-hoc definitions written in imperative languages. We demonstrate four such advantages. First, we illustrate how practical streaming data queries can be easily written with precise semantics. Second, we can get different but expressively equivalent formalisms for defining windows. We use one of them (regular expressions) to design an end-user-friendly language for defining windows. Third, we use another expressively equivalent formalism (automata) to design a processor that automatically generates windows according to specifications. The fourth advantage we demonstrate is more sophisticated. Some window definitions have the problem of too many windows overlapping with each other, overwhelming the processing engine. This is handled in different ways by different engines, but all the options are about what to do when this happens at runtime. We study this as a static analysis question and prove that it is undecidable to check whether such a scenario can ever arise for a given window definition. We identify a decidable fragment..

Smart Monitoring of the Status of Driver Using the Dashboard Vehicle Camera

One of the potential approaches to lessen the quantity of mishaps in rush hour gridlock is to follow the driver's condition. In this paper, a new driver observing calculation, which works on a video caught from the camera situated in the instrument board in the vehicle, is introduced. The calculation analyzes the nearness of the driver's head in each edge and checks whether the driver has bizarrely long closed eyes, regardless of whether the driver looks sideways, and whether the driver's head has dropped for quite a while. The calculation is tried utilizing ten unique recordings recorded under various light conditions. The calculation for the most part accomplishes superior, while for a few lighting conditions a specific calculation redesigning would be vital to keep up an elevated level of precision