48,563 research outputs found
Singularity Free Inhomogeneous Models with Heat Flow
We present a class of singularity free exact cosmological solutions of
Einstein's equations describing a perfect fluid with heat flow. It is obtained
as generalization of the Senovilla class [1] corresponding to incoherent
radiation field. The spacetime is cylindrically symmetric and globally regular.Comment: 6 pages, TeX, to appear in Class.Quant.Gra
Solar Cell Parameters Extraction from a Current- Voltage Characteristic Using Genetic Algorithm
The determination of solar cell parameters is very important for the evaluation of the cell performance as well as to extract maximum possible output power from the cell. In this paper, we propose a computational based binary-coded genetic algorithm (GA) to extract the parameters (I0, Iph and n) for a single diode model of solar cell from its current-voltage (I-V) characteristic. The algorithm was implemented using LabVIEW as a programming tool and validated by applying it to the I-V curve synthesized from the literature using reported values. The values of parameters obtained by GA are in good agreement with those of the reported values for silicon and plastic solar cells. change to “After the validation of the program, it was used to extract parameters for an experimental I-V characteristic of 4 × 4 cm2 polycrystalline silicon solar cell measured under 900 W/m. The I-V characteristic obtained using GA shows excellent match with the experimental one.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3100
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Promoting positive communication environments: a service evaluation.
Purpose
The purpose of this paper is to present an evaluation of a programme of training and support provided to staff, which aimed to encourage supported communication environments for people with learning disabilities.
Design/methodology/approach
Training, monitoring and support for communication, specifically augmentative and alternative communication (AAC) strategies, was provided by speech and language therapy staff to two residential services over 46 weeks. Staff and service user communications were observed pre- and post-intervention.
Findings
In one provision there was an increase in service user initiations and the use of some AAC strategies by support staff. In the other provision there was no change in service user initiations and a decrease in the range of AAC strategies used. It appears that some forms for AAC remain challenging for staff to implement.
Originality/value
This evaluation explores ways of using specialist support services to improve communication environments for people with learning difficulties. Possible reasons for differences in the outcome of the intervention are discussed. Future research into the types of communication interactions experienced by people with learning disabilities across the range of communication styles may be useful so that support staff can be better helped to provide sustained and enriched communication environments
Study of Parasite Hosts of the Genus Cuscuta and its Traditional Uses in Planpur Taluka, Gujarat, India
Cuscuta is a parasitic plant belonging to family Cuscutaceae. The present paper is an investigation of its various host plant species and its traditional uses in Palanpur Taluka of North Gujarat during 2005-2008. Two species of Cuscuta occur in the Palanpur Taluka. The preservation and documentation of traditional knowledge is a matter of prime importance. This will not only provide recognition of this knowledge but will also help in conservation of such gradually vanishing endangered semi/arid plant species. The present paper provide ethnomedicinal information of 2 species of Cuscuta. For each plant species listed, the botanical name, family, vernacular name, part used, uses/ailments treated, preparations/administrations, use (%) and locality are given
Profitability of organic and conventional dairy production with different dietary proportions of high-quality grass silage
Profitability in milk production was calculated using diets with three different proportions of high-quality grass silage. The treatments consisted of the same feeds, but differed in the dietary proportion of forage: low (L), medium (M) and high (H), representing one conventional and two organic diets. The calculations were based on results in feed intake and milk production from a large dairy cow experiment. In the calculations, three different districts with different conditions for farming were used as models, and calculations were performed on two different herd sizes. In addition, current financial supports were both included and excluded in the calculations. The results showed only minor differences in profitability between using in average 60% or 70% of dry matter (DM) of silage in diets used in organic production. In conventional production, it was profitable to increase the average dietary proportion of silage from 50% to 60% of DM when the prices of concentrate and grains were as high as at the present. The results showed clear economic benefits of increasing the proportion of high-quality silage in conventional Scandinavian dairy cow diets up to levels similar to the standards of the organic production system
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