3,864 research outputs found

    qˉq{\bar {q}}q condensate for light quarks beyond the chiral limit

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    We determine the qˉq{\bar{q}}q condensate for quark masses from zero up to that of the strange quark within a phenomenologically successful modelling of continuum QCD by solving the quark Schwinger-Dyson equation. The existence of multiple solutions to this equation is the key to an accurate and reliable extraction of this condensate using the operator product expansion. We explain why alternative definitions fail to give the physical condensate.Comment: 13 pages, 8 figure

    Data on the radio metric survey over a kaolinitic terrain in Dahomey Basin,Nigeria

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    This article consists the insitu data sets of activity concentrations of radio nuclides (K-40,Th-232andU-238) and gamma radiation dose rates measured about 1m above a kaolinitic terrain in Ifo-nyintedo,Dahomey Basin,SW Nigeria.Nineteen(19)data points were randomly occupied at the lower axis of the kaolin field using a hand-held detector known as Super-Spec(RS125).At each data point, the measurements were taken four times,while their averages and standard deviations were estimated in order to ensure accuracy.The radio metric survey was carried out between December,2017andJanuary,2018.The data sets were processed and analyzed via a descriptive statistics. The data can be explored further by estimating the radiological risks to the miners on the field, and to correlate the activity concentrations of the data with the activity concentrations of the tiles that are produced from the kaolin deposits in Ifonyintedo. Furthermore,the data from this article could be compared with other data acquired over a kaoli-nitic terrain across the glob

    Monomial Testing and Applications

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    In this paper, we devise two algorithms for the problem of testing qq-monomials of degree kk in any multivariate polynomial represented by a circuit, regardless of the primality of qq. One is an O(2k)O^*(2^k) time randomized algorithm. The other is an O(12.8k)O^*(12.8^k) time deterministic algorithm for the same qq-monomial testing problem but requiring the polynomials to be represented by tree-like circuits. Several applications of qq-monomial testing are also given, including a deterministic O(12.8mk)O^*(12.8^{mk}) upper bound for the mm-set kk-packing problem.Comment: 17 pages, 4 figures, submitted FAW-AAIM 2013. arXiv admin note: substantial text overlap with arXiv:1302.5898; and text overlap with arXiv:1007.2675, arXiv:1007.2678, arXiv:1007.2673 by other author

    Background radiation dose of dumpsites in Ota and Environs

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    In-situ measurement of background radiation dose from selected dumpsites in Ota and its environs was done using Radialert Nuclear Radiation Monitor (Digilert 200). Ten measurements were taken from each dumpsite. The measured background radiation range between 0.015 mRhr-1 for AOD and 0.028 mRhr-1 for SUS dumpsites. The calculated annual equivalent doses vary between 1.31 mSvyr-1 for AOD and 2.28 mSv/yr for SUS dumpsites. The air absorbed dose calculated ranged from 150 nGyhr-1 to 280 nGy/hr for AOD and SUS dumpsites respectively with an average value of 217 nGyhr-1 for all the locations. All the estimated parameters were higher than permissible limit set for background radiation for the general public. Conclusively, the associated challenge and radiation burden posed by the wastes on the studied locations and scavengers is high. Therefore, there is need by the regulatory authorities to look into the way and how waste can be properly managed so as to alleviate the effects on the populace leaving and working in the dumpsites vicinity

    Review on Li-Fi: an advancement in wireless network communication with the application of solar power

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    Light Fidelity, commonly referred to as Li-Fi is a technology that was introduced by a German physicist called Herald Hass. This technology in its own uniqueness considers the use of light (Light Emitting Diode, LED to be specific) as its medium of delivering high speed communication that complies with standard IEEE 802.15.7 bidirectional communication standard. This optical means of communications is also known as visible light communication. It is safer when compared with Wi-Fi network. This paper will focus on Li-Fi applications, comparison with existing technologies like Wi-Fi and the inclusion of an alternative source of power i.e., solar power, as a means of effectively optimizing on the availability and accessibility of the benefits in places where erratic or total power outage is a common trend

    Data on the radio metric survey over a kaolinitic terrain in Dahomey Basin,Nigeria

    Get PDF
    This article consists the insitu data sets of activity concentrations of radio nuclides (K-40,Th-232andU-238) and gamma radiation dose rates measured about 1m above a kaolinitic terrain in Ifo-nyintedo,Dahomey Basin,SW Nigeria.Nineteen(19)data points were randomly occupied at the lower axis of the kaolin field using a hand-held detector known as Super-Spec(RS125).At each data point, the measurements were taken four times,while their averages and standard deviations were estimated in order to ensure accuracy.The radio metric survey was carried out between December,2017andJanuary,2018.The data sets were processed and analyzed via a descriptive statistics. The data can be explored further by estimating the radiological risks to the miners on the field, and to correlate the activity concentrations of the data with the activity concentrations of the tiles that are produced from the kaolin deposits in Ifonyintedo. Furthermore,the data from this article could be compared with other data acquired over a kaoli-nitic terrain across the glob

    Climate fluctuations and the spring invasion of the North Sea by Calanus finmarchicus

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    The population of Calanus finmarchicus in the North Sea is replenished each spring by invasion from an overwintering stock located beyond the shelf edge. A combincation of field observations, statistical analysis of Continuous Plankton Recorder (CPR) data, and particle tracking model simulations, was used to investigate the processes involved in the cross-shelf invasion. The results showed that the main source of overwintering animals entering the North Sea in the spring is at depths of greater than 600m in the Faroe Shetland Channel, where concentrations of up to 620m -3 are found in association with the overflow of Norwegian Sea Deep Water (NSDW) across the Iceland Scotland Ridge. The input of this water mass to the Faroe Shetland Channel, and hence the supply of overwintering C. finmarchicus, has declined since the late 1960s due to changes in convective processes in the Greenland Sea. Beginning in February, animals start to emerge from the overwintering state and migrate to the surface waters, where their transport into the North Sea is mainly determined by the incidence of north-westerly winds that have declined since the 1960s. Together, these two factors explain a high proportion of the 30-year trends in spring abundance in the North Sea as measured by the CPR survey. Both the regional winds and the NSDW overflow are connected to the North Atlantic Oscillation Index (NAO), which is an atmospheric climate index, but with different time scales of response. Thus, interannual fluctuations in the NAO can cause immediate changes in the incidence of north-westerly winds without leading to corresponding changes in C. finmarchicus abundance in the North Sea, because the NSDW overflow responds over longer (decadal) time scales

    Construction of an in-situ smart device that measures some basic environmental factors for agricultural monitoring

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    Most of the rural agricultural and extension officers have no access to the daily variations in meteorological data that affect the growth and yield of crops. This is as a result of little or no access to the data that could be used to predict the best agricultural practices for optimum output in the rural environments. In this work, a portable and user friendly smart Automated Weather Station (AWS) was constructed. The device that is programmed with Arduino UNO is capable of measuring the temperature, relative humidity and moisture content of the soil. The performance evaluation of the device was observed in the laboratory and onsite (Covenant University farm) both on the sunny and rainy days respectively. It was revealed that there is positive linear relationship between the volume of water added to the soil sample and the soil moisture content in the laboratory measurements. The on-site measurements showed that the temperature is inversely proportional to the relative humidity and soil moisture content. This device is efficient in taking the short-term essential parameters that could improve the yield of agricultural products in the rural environments if properly utilized

    A hybrid neuro--wavelet predictor for QoS control and stability

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    For distributed systems to properly react to peaks of requests, their adaptation activities would benefit from the estimation of the amount of requests. This paper proposes a solution to produce a short-term forecast based on data characterising user behaviour of online services. We use \emph{wavelet analysis}, providing compression and denoising on the observed time series of the amount of past user requests; and a \emph{recurrent neural network} trained with observed data and designed so as to provide well-timed estimations of future requests. The said ensemble has the ability to predict the amount of future user requests with a root mean squared error below 0.06\%. Thanks to prediction, advance resource provision can be performed for the duration of a request peak and for just the right amount of resources, hence avoiding over-provisioning and associated costs. Moreover, reliable provision lets users enjoy a level of availability of services unaffected by load variations
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