300 research outputs found
Evaluating Distributed Time-Varying Generation Through a Multiobjective Index
In the last decade, distributed generation, with its various technologies, has increased its presence in the energy mix presenting distribution networks with challenges in terms of evaluating the technical impacts that require a wide range of network operational effects to be qualified and quantified. The inherent time-varying behavior of demand and distributed generation (particularly when renewable sources are used), need to be taken into account since considering critical scenarios of loading and generation may mask the impacts. One means of dealing with such complexity is through the use of indices that indicate the benefit or otherwise of connections at a given location and for a given horizon. This paper presents a multiobjective performance index for distribution networks with time-varying distributed generation which consider a number of technical issues. The approach has been applied to a medium voltage distribution network considering hourly demand and wind speeds. Results show that this proposal has a better response to the natural behavior of loads and generation than solely considering a single operation scenario
Evaluating distributed generation impacts with a multiobjective index
Evaluating the technical impacts associated with connecting distributed generation to distribution networks is a complex activity requiring a wide range of network operational and security effects to be qualified and quantified. One means of dealing with such complexity is through the use of indices that indicate the benefit or otherwise of connections at a given location and which could be used to shape the nature of the contract between the utility and distributed generator. This paper presents a multiobjective performance index for distribution networks with distributed generation which considers a wide range of technical issues. Distributed generation is extensively located and sized within the IEEE-34 test feeder, wherein the multiobjective performance index is computed for each configuration. The results are presented and discussed
Uniqueness of positive solutions for boundary value problems associated with indefinite \u3c6-Laplacian-type equations
This paper provides a uniqueness result for positive solutions of the Neumann and periodic boundary value problems associated with the \u3c6-Laplacian equation 'Equation Presented', where \u3c6 is a homeomorphism with \u3c6(0) = 0, a(t) is a stepwise indefinite weight and g(u) is a continuous function. When dealing with the p-Laplacian differential operator \u3c6(s) = |s|p-2s with p > 1, and the nonlinear term g(u) = u\u3b3 with \u3b3 08 \u211d, we prove the existence of a unique positive solution when \u3b3 \u3f5 ]- 1e, (1 - 2p)/(p - 1)] 2a ]p - 1, + 1e[
Study on the suitable lighting design of Beato Angelico’s artworks displayed at the National Museum of San Matteo in Pisa (Italy)
The lighting design of exhibition space has a great impact on visual and colour
perception and different lighting arrangements can create very different visual impression of
artworks and, if not carefully designed, compromise the enjoyment of the viewers. This study
involved the design of a new lighting solution for two of Beato Angelico’s artworks displayed
at the National Museum of San Matteo (Pisa, Italy). Multiple test lighting configurations were
designed using different LED luminaires and different settings of the luminaires. The test
lighting configurations were evaluated by a restricted group of observers through a survey in
order to individuate the most suitable solution, able to enhance the two artworks
simultaneously and to provide a good visual experience for museum visitors
Seletividade de herbicidas e reguladores de crescimento de plantas utilizados na cultura da cana-de-açúcar para imaturos de Trichogramma galloi (Hymenoptera: Trichogrammatidae).
Multiobjective optimization model for the connection of wind power generation to distribution networks
primary cutaneous cd30 anaplastic large cell lymphoma in a heart transplant patient case report and literature review
Solid organ transplant recipients are at risk of develop ing a wide range of viral-associated malignancies, in cluding skin tumours and lymphoproliferative disorders. The risk of a post-transplant lymphoproliferative disorder is 28–49 times the risk of a lymphoproliferative disorder in the normal population. Most cases are of B-cell phenotype and are associated with Epstein-Barr virus infection. Post-transplant lymphoproliferative disorders presenting clinically in the skin are rare and usually of B-cell phenotype. Only rare cases of cutaneous T-cell post-transplant lymphoproliferative disorder have been reported previously, mostly mycosis fungoides type. We describe here a rare primary cutaneous T-cell lymphoma CD30+ arising in a heart transplant patient who had a nodule on the right leg, several years after heart transplantation. The morphology and immunohistochemical findings were consistent with a CD30+ anaplastic large cell lymphoma with a T-cell phenotype. Excisional biopsy and radiotherapy of the affected area were performed. In this patient, the presence of a solitary lesion and th
Positive solutions to indefinite Neumann problems when the weight has positive average
We deal with positive solutions for the Neumann boundary value problem
associated with the scalar second order ODE where is positive on and is an indefinite weight. Complementary to previous
investigations in the case , we provide existence results
for a suitable class of weights having (small) positive mean, when
at infinity. Our proof relies on a shooting argument for a suitable equivalent
planar system of the type with
a continuous function defined on the whole real line.Comment: 17 pages, 3 figure
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