Rotated Rectangular Slots And Mirrored Inversed Cantor-sets On Ultrawideband Antipodal Vivaldi Antenna

Variants of antipodal Vivaldi antenna (AVA) design suitable for access point working on 0.5 – 6.0 GHz are proposed in this paper. The novel designs were produced by employing three novel techniques to conventional AVA: (i) rotated-slot pattern to shift down the frequency cutoff and enhancing bandwidth, (ii) curve design to miniaturize rotated-slot-inserted antipodal Vivaldi, and (iii) fractal-director (Cantor set) to increase the gain of antipodal Vivaldi. Using FR4 (relative permittivity of 4.4) with an overall dimension of 300 mm x 143 mm x 1.6 mm the antenna designs are able to work at a frequency of 0.472 GHz to higher than 6 GHz with a maximum gain of 11.9 dBi

Non equilibrium thermodynamics and cosmological pancakes formation

We investigate the influence of non equilibrium thermodynamics on cosmological structure formation. In this paper, we consider the collapse of planar perturbations usually called "Zel'dovich pancakes". We have developed for that purpose a new two fluids (gas and dark matter) hydrodynamical code, with three different thermodynamical species: electrons, ions and neutral particles (T_e\ne T_i \ne T_n). We describe in details the complex structure of accretion shock waves. We include several relevant processes for a low density, high temperature, collisional plasma such as non-equilibrium chemical reactions, cooling, shock heating, thermal energy equipartition between electrons, ions and neutral particles and electronic conduction. We find two different regions in the pancake structure: a thermal precursor ahead of the compression front and an equipartition wave after the compression front where electrons and ions temperatures differ significantly. This complex structure may have two interesting consequences: pre-heating of unshocked regions in the vicinity of massive X-ray clusters and ions and electrons temperatures differences in the outer regions of X-rays clusters.Comment: 30 pages, including 8 figures, accepted for publication in The Astrophysical Journa

The Role of Dukun Suwuk and Dukun Prewangan in Curing Diseases in Kediri Community

Finding a cure when people get sick is an important thing. One of the efforts done by Kediri people in finding for a cure is to come to a Dukun (Shaman/traditional healer) Suwuk and Dukun Prewangan. The purposes of this research are to know the profiles and methods of Dukun Suwuk and Dukun Prewangan, and their role in curing diseases. This research used descriptive qualitative method. The results of this research show that (1) the process of healing and problem solution performed by Dukun Suwuk uses prayer as a key source of power. And Dukun Prewangan uses the help of supernatural beings who become their working partners to cure or resolve the problem, (2) Dukun Suwuk and Dukun Prewangan has an important role in society because of their presence is needed and respected. In addition, Dukun Suwuk and Dukun Prewangan who have been offering the services had experienced a lot of things as a living experience, (3) healing process performed by Dukun Suwuk and Dukun Prewangan is one solution for patients to be free from the ambiguous conditions of liminal stage. Choosing to go to a traditional healer healing is a rational choice for each patient

Generalized Brans-Dicke cosmology in the presence of matter and dark energy

We study the Generalized Brans-Dicke cosmology in the presence of matter and dark energy. Of particular interest for a constant Brans-Dicke parameter, the de Sitter space has also been investigated.Comment: 9 page

Correspondence between kinematical backreaction and scalar field cosmologies - the `morphon field'

Spatially averaged inhomogeneous cosmologies in classical general relativity can be written in the form of effective Friedmann equations with sources that include backreaction terms. In this paper we propose to describe these backreaction terms with the help of a homogeneous scalar field evolving in a potential; we call it the `morphon field'. This new field links classical inhomogeneous cosmologies to scalar field cosmologies, allowing to reinterpret, e.g., quintessence scenarios by routing the physical origin of the scalar field source to inhomogeneities in the Universe. We investigate a one-parameter family of scaling solutions to the backreaction problem. Subcases of these solutions (all without an assumed cosmological constant) include scale-dependent models with Friedmannian kinematics that can mimic the presence of a cosmological constant or a time-dependent cosmological term. We explicitly reconstruct the scalar field potential for the scaling solutions, and discuss those cases that provide a solution to the Dark Energy and coincidence problems. In this approach, Dark Energy emerges from morphon fields, a mechanism that can be understood through the proposed correspondence: the averaged cosmology is characterized by a weak decay (quintessence) or growth (phantom quintessence) of kinematical fluctuations, fed by `curvature energy' that is stored in the averaged 3-Ricci curvature. We find that the late-time trajectories of those models approach attractors that lie in the future of a state that is predicted by observational constraints.Comment: 36 pages and 6 Figures, matches published version in Class.Quant.Gra

Cosmological Backreaction from Perturbations

We reformulate the averaged Einstein equations in a form suitable for use with Newtonian gauge linear perturbation theory and track the size of the modifications to standard Robertson-Walker evolution on the largest scales as a function of redshift for both Einstein de-Sitter and Lambda CDM cosmologies. In both cases the effective energy density arising from linear perturbations is of the order of 10^-5 the matter density, as would be expected, with an effective equation of state w ~ -1/19. Employing a modified Halofit code to extend our results to quasilinear scales, we find that, while larger, the deviations from Robertson-Walker behaviour remain of the order of 10^-5.Comment: 15 pages, 8 figures; replaced by version accepted by JCA

Financial Intermediation In Agriculture In Nigeria: Emerging Role Of Non- Governmental Organizations (Ngos)

The study compared the credit operations of Farmers Development Union (FADU) - an NGO, with the Nigerian Agricultural Cooperative and Rural Development Bank (NACRDB) - a public sector finance agency in agricultural financing with a view to determining the emerging roles of NGOs in Nigeria's agricultural landscape. To achieve this, the socio-economic characteristics of farmers who use credit, and the performance of the selected credit institutions on the basis of credit delivery and loan repayment were identified and analysed using descriptive, t-test statistic and regression analyses. The results of the study revealed that theoperational flexibility of the NGO was its major appeal to farmers. The use of groups as social assets for collateral instead of physical assets increased the vibrancy of the NGO compared to the public finance agency and provided a level playing field for both male and female farmers inthe credit market. Patrons of the NGO made a mean savings of N22,284 whereas those of the public finance agency saved only N13,472. While the NGO disbursed more credit to its clients compared to the public finance agency, it also recovered 68.5% of its loans compared with 49.3% recovery made by the public finance agency. If formal banks will be able to impact on small farmers as the NGO, they will need to provide non-collaterized loans and to groups rather than individuals.Keywords: agricultural financing, farm capitalization, credit disbursement and loan recovery

Scalar-Tensor Cosmological Models

We analyze the qualitative behaviors of scalar-tensor cosmologies with an arbitrary monotonic $\omega(\Phi)$ function. In particular, we are interested on scalar-tensor theories distinguishable at early epochs from General Relativity (GR) but leading to predictions compatible with solar-system experiments. After extending the method developed by Lorentz-Petzold and Barrow, we establish the conditions required for convergence towards GR at $t\rightarrow\infty$. Then, we obtain all the asymptotic analytical solutions at early times which are possible in the framework of these theories. The subsequent qualitative evolution, from these asymptotic solutions until their later convergence towards GR, has been then analyzed by means of numerical computations. From this analysis, we have been able to establish a classification of the different qualitative behaviors of scalar-tensor cosmological models with an arbitrary monotonic $\omega(\Phi)$ function.Comment: uuencoded compressed postscript file containing 41 pages, with 9 figures, accepted for publication in Physical Review