Primary power distribution systems planning taking into account reliability, operation and expansion costs

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Circuit board accident - organizational dimension hidden by prescribed safety

This study analyzes an accident in which two maintenance workers suffered severe burns while replacing a circuit breaker panel in a steel mill, following model of analysis and prevention of accidents (MAPA) developed with the objective of enlarging the perimeter of interventions and contributing to deconstruction of blame attribution practices. The study was based on materials produced by a health service team in an in-depth analysis of the accident. The analysis shows that decisions related to system modernization were taken without considering their implications in maintenance scheduling and creating conflicts of priorities and of interests between production and safety; and also reveals that the lack of a systemic perspective in safety management was its principal failure. To explain the accident as merely non-fulfillment of idealized formal safety rules feeds practices of blame attribution supported by alibi norms and inhibits possible prevention. In contrast, accident analyses undertaken in worker health surveillance services show potential to reveal origins of these events incubated in the history of the system ignored in practices guided by the traditional paradigm.

DNA barcoding reveals hidden diversity in the Neotropical freshwater fish Piabina argentea (Characiformes: Characidae) from the Upper Parana Basin of Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

DNA barcoding of Podonomus (Chironomidae, Podonominae) enables stage association of a named species and reveals hidden diversity in Brazilian inselbergs

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Habits hidden underground: a review on the reproduction of the Amphisbaenia with notes on four neotropical species

We review the information currently available on the reproduction of the Amphisbaenia and provide original data on the reproductive biology of four Neotropical species: Amphisbaena alba; A. mertensi; Cercolophia roberti, and Leposternon infraorbitale. In total, we compiled data for 22 species: 17 Amphisbaenidae, 1 Rhineuridae, 3 Bipedidae, and 1 Trogonophidae. The majority of the species were oviparous with the exceptions of Loveridgea ionidesii, Monopeltis anchietae, M. capensis, and Trogonophis wiegmanni. Viviparity was interpreted as a derived trait that evolved independently for at least 3 times within the Amphisbaenia. In most species, reproduction is synchronized with the hot and rainy season and seems to vary with latitude. Although Amphisbaenia eggs have been found in ant nests, it remains disputable whether this is an obligatory or even a preferable location for egg-laying. Incubation time in A. mertensii lasts 59 days and this is the first report encompassing egg-laying to hatching for any Amphisbaenia species. Nonetheless, a two months incubation period seems to be the common rule for oviparous Amphisbaenia. The general pattern of reproductive output in Amphisbaenia is characterized by a low number of eggs/embryos per clutch whose individual size is comparatively large in relation to adult body size. Eggs are markedly elongated on the long axis and arranged in-line within the abdominal cavity possibly to prevent/diminish biomechanic drawbacks of egg bearing. Hatchlings of A. mertensi possess an egg-tooth implanted at the upper jaw, exhibit positive geotropism, and display defensive behaviors known to be present in adults. Our review shows that our current knowledge of Amphisbaenia reproduction is fragmentary, often based on the examination of small samples, and heavily dependent on the publication of anedoctal observations. Future publications on this subject are encouraged.

An approach using Lagrangian/surrogate relaxation for lot-sizing with transportation costs

Neste trabalho estuda-se um problema de dimensionamento de lotes e distribuição que envolve além de custos de estoques, produção e preparação, custos de transportes para o armazém da empresa. Os custos logísticos estão associados aos contêineres necessários para empacotar os produtos produzidos. A empresa negocia um contrato de longo prazo onde um custo fixo por período é associado ao transporte dos itens, em contrapartida um limite de contêineres é disponibilizado com custo mais baixo que o custo padrão. Caso ocorra um aumento ocasional de demanda, novos contêineres podem ser utilizados, no entanto, seu custo é mais elevado. Um modelo matemático foi proposto na literatura e resolvido utilizando uma heurística Lagrangiana. No presente trabalho a resolução do problema por uma heurística Lagrangiana/surrogate é avaliada. Além disso, é considerada uma extensão do modelo da literatura adicionando restrições de capacidade e permitindo atraso no atendimento a demanda. Testes computacionais mostraram que a heurística Lagrangiana/surrogate é competitiva especialmente quando se têm restrições de capacidade apertada.

Hidden sector effects on double Higgs production near threshold at the LHC

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for Dark Photons from Supersymmetric Hidden Valleys

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Costs estimates and rentability of the guava culture (Psidium guajava L Paluma cv) in Monte Alto County, São Paulo State

This work intended to calculate the rentability of the guava culture Paluma cv. in Monte Alto region-SP, estimating the costs of the implantation, maintenance, production and the gross income of this culture in the first three years of cultivation. The production system utilized refers to the cultural treatments usually used in this culture in the region. The costs estimates were based on the total operational costs methodology used by the Agricultural Economics Institute (I.E.A.). The results obtained showed that the implantation and maintenance costs of the culture, in the two first years was R$7.402,3 l/alqueire*. Considering the possibility that in guava orchard, on irrigated conditions, reach in the fourthy year a productivity of 80t/alqueire and that the current price is R$0,20/kg, it is possible to estimate the gross income around of R$16.000,00/alqueire, resulting in a net income of R$9.497,06/alqueire.

Ladder operators for subtle hidden shape-invariant potentials

Ladder operators can be constructed for all potentials that present the integrability condition known as shape invariance, satisfied by most of the exactly solvable potentials. Using the superalgebra of supersymmetric quantum mechanics, we construct the ladder operators for two exactly solvable potentials that present a subtle hidden shape invariance.

Allocation of the costs of transmission losses

An analysis of the performance of six major methods of loss allocation for generators and demands was conducted, based on pro-rata (two), on incremental factors (two), on proportional sharing (PS) (one), and on electric circuit theory (one). Using relatively simple examples which can easily be checked, the advantages and disadvantages of each were ascertained and the results confirmed using a larger sample system (IEEE-118). The discussion considers the location and size of generators and demands, as well as the merits of the location of these agents for each configuration based on an analysis of the effect of various network modifications. Furthermore, an application in the South-Southeastern Brazilian Systems is performed. Conclusions and recommendations are presented. (C) 2004 Elsevier B.V. All rights reserved.

Costs estimates and rentability of the guava culture {psidium guajava l. patuma cv.) in monte alto county, Sao Paulo state

This work intended to calculate the rentability of the guava culture Paluma cv. in Monte Alto region-SP, estimating the costs of the implantation, maintenance, production and the gross income of this culture in the first three years of cultivation. The production system utilized refers to the cultural treatments usually used in this culture in the region. The costs estimates were based on the total operational costs methodology used by the Agricultural Economics Institute (I.E.A.). The results obtained showed that the implantation and maintenance costs of the culture, in the two first years was Rs7.402,31/alqueire. Considering the possibility that in guava orchard, on irrigated conditions, reach in the fourthy year a productivity of 80t/alqueire and that the current price is Rs0,20/kg, it is possible to estimate the gross income around of Rs16.000,00/alqueire, resulting in a net income of Rs9.497,06/alqueire.

The sugar cane vegetal residues unloaded in the sugar mill: Operational costs and physical characteristics

Brazil produced in 2002/03 season 317.87×106tons of sugar cane stalks and 36.88×106tons of vegetal residues (green leaves, dry leaves and tops) in a planted area of 4.61×106 hectares (ha). These residues have a useful heat of 3,613.14Mcal.t-1. Currently most of this biomass is burned as a pre-harvest practice. The doubt persists in the system type that it must be adopted to pick up, load, transport and unload this biomass at the sugar mill boilers. This study analyzed 22 variables related to operational costs and physical characteristics of these residues in a field situation using a JOHN DEERE® 6850 forage harvester with two different treatments: T1 and T2 (two types of rakes) with 6 repetitions each one. The geographic location of the studied area that belongs to COSTA PINTO MILL (COSAN® Group) is: Latitude 22°40'30S and Longitude 47°36'38W. The adopted methodology was proposed by Ripoli et al. (2002). The obtained results at a 5% level of significance showed that both treatments did not differed significantly between them. Some of the results were, where EBP stands for Oil Equivalent Barrel: Windrowing (T1=US$0.17.EBP-1 and US$9.59.ha-1, T2=US$0.08.EBP-1 and US$4.27.ha-1); Pick up (T1=US$1.31.EBP-1 and US$44.29.ha-1, T2 =US$1.37.EBP-1 and US$48.36.ha-1); Transportation (T1=US$1.27.EBP-1 and US$14,30.ha -1, T2=US$1.33.EBP-1 and US$14,80.ha -1), Unloading at the sugar mill (T1=US$0.30.EBP-1 and US$3.39.ha-1, T2=US$0.32.EBP-1 and US$3.51.ha-1); Total (T1=US$3.05.EBP-1 and US$71.57.ha-1, T2=US$3.10.EBP-1 and US$70.94.ha-1). Confronting the obtained data with the ones in the bibliography, this system revealed itself more expensive than the baling system or the integral harvest system using combines.