Simplest Cubic Fields

Let $Q(\alpha)$ be the simplest cubic field, it is known that $Q(\alpha)$ can be generated by adjoining a root of the irreducible equation $x^{3}-kx^{2}+(k-3)x+1=0$, where $k$ belongs to $Q$. In this paper we have established a relationship between $\alpha$, $\alpha'$ and $k,k'$ where $\alpha$ is a root of the equation $x^{3}-kx^{2}+(k-3)x+1=0$ and $\alpha'$ is a root of the same equation with $k$ replaced by $k'$ and $Q(\alpha)=Q(\alpha')$

Signal Detection for QPSK Based Cognitive Radio Systems using Support Vector Machines

Cognitive radio based network enables opportunistic dynamic spectrum access by sensing, adopting and utilizing the unused portion of licensed spectrum bands. Cognitive radio is intelligent enough to adapt the communication parameters of the unused licensed spectrum. Spectrum sensing is one of the most important tasks of the cognitive radio cycle. In this paper, the auto-correlation function kernel based Support Vector Machine (SVM) classifier along with Welch's Periodogram detector is successfully implemented for the detection of four QPSK (Quadrature Phase Shift Keying) based signals propagating through an AWGN (Additive White Gaussian Noise) channel. It is shown that the combination of statistical signal processing and machine learning concepts improve the spectrum sensing process and spectrum sensing is possible even at low Signal to Noise Ratio (SNR) values up to -50 dB

A rural agricultural-sustainable energy community model and its application to Felton Valley, Australia

Energy and food security require a delicate balance which should not threaten or undermine community prosperity. Where it is proposed to derive energy from conventional fossil fuel resources (such as coal, shale oil, natural gas, coal seam gas) located in established rural areas, and particularly where these areas are used for productive agricultural purposes, there are often both intense community concern as well as broader questions regarding the relative social, economic and environmental costs and benefits of different land uses and, increasingly, different energy sources. The advent of mainstream renewable energy technologies means that alternative energy options may provide a viable alternative, allowing energy demand to be met without compromising existing land uses. We demonstrate how such a Sustainable Energy Rural Model can be designed to achieve a balance between the competing social goals of energy supply, agricultural production, environmental integrity and social well-being, and apply it to the Felton Valley, a highly productive and resilient farming community in eastern Australia. Research into available wind and solar resources found that Felton Valley has a number of attributes that indicate its suitability for the development of an integrated renewable energy precinct which would complement, rather than displace, existing agricultural enterprises. Modelling results suggest a potential combined annual renewable energy output from integrated wind and solar resources of 1,287 GWh/yr from peak installed capacity of 713 MW, sufficient to supply the electrical energy needs of about 160,000 homes, in combination with total biomass food production of 31,000 tonnes per annum or 146 GWh/yr of human food energy. The portfolio of renewable energy options will not only provide energy source diversity but also ensures long-term food security and regional stability. The Felton Valley model provides an example of community-led energy transformation and has potential as a pilot project for the development of smart distributed grids that would negate the need for further expansion of coal mining and coal fired power stations

Finite AG-groupoid with left identity and left zero

A groupoid G whose elements satisfy the left invertive law: (ab)c=(cb)a is known as Abel-Grassman's groupoid (AG-groupoid). It is a nonassociative algebraic structure midway between a groupoid and a commutative semigroup. In this note, we show that if G is a finite AG-groupoid with a left zero then, under certain conditions, G without the left zero element is a commutative group

Dietary supplementation with n-3 fatty acids (n-3 FA) for 4 weeks reduces post-exercise fatigue and delayed onset muscle soreness (DOMS) in trained male athletes

This article has been accepted for publication and will appear in a revised form, subsequent to peer review and/or editorial input by Cambridge University Press, in Proceedings of the Nutrition Society published by Cambridge University Press. Copyright The Authors 2015.High intensity exercise in the form of eccentric contractions can lead to the formation of free radicals, stimulating an inflammatory response( 1 , 2 ). Consumption of n-3 FA may help modify inflammation and immune reactions beneficial to health by decreasing interleukin-6, tumour necrosis factor-alpha and C-reactive protein( 3 ). For trained athletes to improve athletic performance, recovery from training is important and DOMS is frequently experienced following eccentric exercise, impacting negatively on strength( 4 ). The Western diet is however, characterised by a high n-6 FA consumption relative to n-3 FA, formulating ratios often in excess of 16:1( 5 ). The use of non-steroidal anti-inflammatory drugs in the form of n-3 FA has been investigated by a number of clinical trials in untrained athletes, but whether this can be translated into attenuating exercise induced inflammation in trained athletes is still under investigation. A double-blind, randomised controlled trial was conducted in 22 trained male athletes who supplemented their diet with either 3000 mg/d of fish oil (gel capsules) consisting of 990 mg eicosapentaenoic acid (EPA) and 660 mg docosahexaenoic acid (DHA) (n = 11), or 3000 mg/d olive oil placebo (n = 11), for 28d. Participants underwent 3 sets of eccentric bicep curls in their dominant arm until failure and arm circumference, number of repetitions completed and DOMS/fatigue scores via visual analogue scale (VAS) were recorded at 0, 24 and 48 h after exercise, pre and post supplementation. No group performed better during the eccentric bicep test, pre and post supplementation, and at baseline, no differences were observed between groups for DOMS and fatigue. However, post supplementation, DOMS was significantly lower at 24 h (P = 0·005) and 48 h (P = 0·002) and fatigue was significantly lower at 24 h (P = 0·043) and 48 h post exercise (P < 0·001) in the n-3 FA group compared to the placebo group (Fig. 1). These findings indicate that n-3 FA supplementation has the potential to promote recovery and subsequently increase athletic performance in trained male athletes and may be a useful ergogenic aid. Possible anti-inflammatory mechanisms of n-3 FA should be further investigated using specific biomarkers of inflammation

Wasteland reclamation strategy for household timber security of tribes in Jharkhand, India

The study sought to examine the timber dependency on forests and evolve wasteland reclamation strategy to eliminate the forest dependency in Bundu block of Ranchi District in Jharkhand, India. Multi-stage random sampling technique was applied to select 164 tribal households from 9 sample villages. Data were collected using structured interviews and non-participant observations which were analyzed using descriptive statistics viz., frequency, percentage, mean and range. Results revealed that forests contributed maximum timber (136.36 m3 annum-1) followed by traditional agroforestry (69.09 m3 annum-1), community forestry (41.33 m3 annum-1) and homestead forestry (35.71 m3 annum-1). Timber extracted is mostly consumed in housing (124.66 m3 annum-1) followed by agricultural implements (82.71 m3 annum-1), furniture (35.25 m3 annum-1), carts/ carriages (17.60 m3 annum-1), fencing (10.23 m3 annum-1), cattle shed/ store house (9.10 m3 annum-1) and others (2.94 m3 annum-1). Forests were exposed to timber pressure of 136.36 m3 annum-1 (48.27%) posing ample deforestation and degradation. The strategy consisted of timber and bamboo plantations is designed which would secure 1065.60 m3 annum-1 of timber, 0.455 lakh annum-1 of bamboo culms, 568.26 tons annum-1 of bamboo leaf and agricultural products. The strategy would yield income of Rs. 34210.78 household-1 annum-1 and employment of 67.15 person-days household-1 annum-1. Financial viability of proposed interventions has been worked out by meticulous economic calculations of Net Present Value, Benefit Cost Ratio and Internal Rate of Return. The execution of strategy would eliminate the current unsustainable timber extraction, safeguard the future timber predicament and ensure environmental security

On the Estrada index of unicyclic and bicyclic signed graphs

Let $\Gamma=(G, \sigma)$ be a signed graph of order $n$ with eigenvalues $\mu_1,\mu_2,\ldots,\mu_n.$ We define the Estrada index of a signed graph $\Gamma$ as $EE(\Gamma)=\sum_{i=1}^ne^{\mu_i}$. We characterize the signed unicyclic graphs with the maximum Estrada index. The signed graph $\Gamma$ is said to have the pairing property if $\mu$ is an eigenvalue whenever $-\mu$ is an eigenvalue of $\Gamma$ and both $\mu$ and $-\mu$ have the same multiplicities. If $\Gamma_{p}^-(n, m)$ denotes the set of all unbalanced graphs on $n$ vertices and $m$ edges with the pairing property, we determine the signed graphs having the maximum Estrada index in $\Gamma_{p}^-(n, m)$, when $m=n$ and $m=n+1$. Finally, we find the signed graphs among all unbalanced complete bipartite signed graphs having the maximum Estrada index.Comment: 16 pages, 2 figure

Structured hydrological analysis for targeting fallow evaporation to improve water productivity at the irrigation system level

International audienceThis paper provides results of an application of a holistic systematic approach of water accounting using remote sensing and GIS coupled with ground water modeling to evaluate water saving options by tracking non-beneficial evaporation in the Liuyuankou Irrigation System (LIS) of China. Groundwater rise is a major issue in the LIS, where groundwater levels have risen alarmingly close to the ground surface (within 1 m) near the Yellow River. The lumped water balance analysis showed high fallow evaporation losses and which need to be reduced for improving water productivity. The seasonal actual evapotranspiration (ETs) was estimated by applying the SEBAL algorithm for eighteen NOAA AVHRR-12 images over the year of 1990?1991. This analysis was aided by the unsupervised land use classification applied to two Landsat 5 TM images of the study area. SEBAL results confirmed that a significant amount (116.7 MCM) of water can be saved by reducing ETs from fallow land which will result in improved water productivity at the irrigation system. The water accounting indicator (for the analysis period) shows that the process fraction per unit of depleted water (PFdepleted) is 0.52 for LIS, meaning that 52% of the depleted water is consumed by agricultural crops and 48% is lost through non-process depletion. Finally, the groundwater modeling was applied to simulate three land use and water management interventions to assess their effectiveness for both water savings and impact on the groundwater in LIS. MODFLOW's Zone Budget code calculates the groundwater budget of user-specified subregions, the exchange of flows between subregions and also calculates a volumetric water budget for the entire model at the end of each time step. The simulation results showed that fallow evaporation could be reduced between 14.2% (25.51 MCM) and 45.3% (81.36 MCM) by interventions such as canal lining and ground water pumping. The reduction in non-beneficial ETs volumes would mean that more water would be available for other uses and it would allow the introduction of more surface water supplies in the area through improved water management strategies. This will ultimately lead to improved water productivity of the LIS system