A combinatorial flow-based formulation for temporal bin packing problems

We consider two neighboring generalizations of the classical bin packing problem: the temporal bin packing problem (TBPP) and the temporal bin packing problem with fire-ups (TBPP-FU). In both cases, the task is to arrange a set of given jobs, characterized by a resource consumption and an activity window, on homogeneous servers of limited capacity. To keep operational costs but also energy consumption low, TBPP is concerned with minimizing the number of servers in use, whereas TBPP-FU additionally takes into account the switch-on processes required for their operation. Either way, challenging integer optimization problems are obtained, which can differ significantly from each other despite the seemingly only marginal variation of the problems. In the literature, a branch-and-price method enriched with many preprocessing steps (for TBPP) and compact formulations (for TBPP-FU), benefiting from numerous reduction methods, have emerged as, currently, the most promising solution methods. In this paper, we introduce, in a sense, a unified solution framework for both problems (and, in fact, a wide variety of further interval scheduling applications) based on graph theory. Any scientific contributions in this direction failed so far because of the exponential size of the associated networks. The approach we present in this article does not change the theoretical exponentiality itself, but it can make it controllable by clever construction of the resulting graphs. In particular, for the first time all classical benchmark instances (and even larger ones) for the two problems can be solved – in times that significantly improve those of the previous approaches

Toward a test of angular momentum coherence in a twin-atom interferometer

We present a scheme well-suited to investigate quantitatively the angular momentum coherence of molecular fragments. Assuming that the dissociated molecule has a null total angular momentum, we investigate the propagation of the corresponding atomic fragments in the apparatus. We show that the envisioned interferometer enables one to distinguish unambiguously a spin-coherent from a spin-incoherent dissociation, as well as to estimate the purity of the angular momentum density matrix associated with the fragments. This setup, which may be seen as an atomic analogue of a twin-photon interferometer, can be used to investigate the suitability of molecule dissociation processes -- such as the metastable hydrogen atoms H($2^2 S$)-H($2^2 S$) dissociation - for coherent twin-atom optics.Comment: 6 pages, 3 Figures. Final version accepted for publication in Europhysics Letter

Estrutura de uma floresta de terra firme na região de Marabá-PA: a posição do mogno em relação ás outras espécies da comunidade.

bitstream/item/39905/1/Com-Tec-22-Am-Oriental.pd

Cosmological constant constraints from observation-derived energy condition bounds and their application to bimetric massive gravity

Among the various possibilities to probe the theory behind the recent accelerated expansion of the universe, the energy conditions (ECs) are of particular interest, since it is possible to confront and constrain the many models, including different theories of gravity, with observational data. In this context, we use the ECs to probe any alternative theory whose extra term acts as a cosmological constant. For this purpose, we apply a model-independent approach to reconstruct the recent expansion of the universe. Using Type Ia supernova, baryon acoustic oscillations and cosmic-chronometer data, we perform a Markov Chain Monte Carlo analysis to put constraints on the effective cosmological constant $\Omega^0_{\rm eff}$. By imposing that the cosmological constant is the only component that possibly violates the ECs, we derive lower and upper bounds for its value. For instance, we obtain that $0.59 < \Omega^0_{\rm eff} < 0.91$ and $0.40 < \Omega^0_{\rm eff} < 0.93$ within, respectively, $1\sigma$ and $3\sigma$ confidence levels. In addition, about 30\% of the posterior distribution is incompatible with a cosmological constant, showing that this method can potentially rule it out as a mechanism for the accelerated expansion. We also study the consequence of these constraints for two particular formulations of the bimetric massive gravity. Namely, we consider the Visser's theory and the Hassan and Roses's massive gravity by choosing a background metric such that both theories mimic General Relativity with a cosmological constant. Using the $\Omega^0_{\rm eff}$ observational bounds along with the upper bounds on the graviton mass we obtain constraints on the parameter spaces of both theories.Comment: 11 pages, 4 figures, 1 tabl

Dark matter from cosmic defects on galactic scales?

We discuss the possible dynamical role of extended cosmic defects on galactic scales, specifically focusing on the possibility that they may provide the dark matter suggested by the classical problem of galactic rotation curves. We emphasize that the more standard defects (such as Goto-Nambu strings) are unsuitable for this task, but show that more general models (such as transonic wiggly strings) could in principle have a better chance. In any case, we show that observational data severely restricts any such scenarios.Comment: Submitted to Phys. Rev. D (Brief Reports). v2: Reference added and some typos corrected, matches published versio

Efeito da somatotropina bovina recombinante (bst) sobre a produção de leite de cabras Saanen e Anglo Nubiana.

O presente trabalho, realizado na Embrapa Caprinos, Sobral-CE, avaliou o efeito da somatotropina bovina recombinante (bST) sobre a produção de leite de cabras Saanen e Anglo Nubiana, recebendo dois níveis de concentrado. Foram usadas 30 cabras, entre a segunda e quarta ordem de parição, divididas em dois grupos, de acordo com a quantidade de concentrado fornecida: 1,0 kg/animal/dia e 1,25 kg/animal/dia. Cada grupo foi subdividido em dois tratamentos, sendo fornecido 0 mg/kg.PV e 3,0 mg/kg.PV de bST. As análises estatísticas foram realizadas por meio do procedimento GLM, utilizando o modelo que incluiu os efeitos fixos de raça, níveis de concentrado, interação raça x níveis de concentrado, bST e suas interações e a variável dia de lactação (efeitos linear e quadrático). Houve efeito (P<0,01) de raça, níveis de concentrado e da aplicação do bST sobre a produção de leite, sendo significativa (P<0,01) apenas a interação raça x níveis de concentrado. A produção de leite foi maior (P<0,05) para a Saanen em relação a Anglo Nubiana apenas no tratamento com menor nível de concentrado. Para a Anglo Nubiana, a quantidade de concentrado fornecida afetou (P<0,05) a produção de leite. A produção de leite aumentou (P<0,05) com a aplicação de bST, de 1,73 kg/aniamal/dia para 2,04 kg/animal/dia. Conclui-se, portanto, que a produção de leite de cabras Saanen e Anglo Nubiana pode ser incrementada com a aplicação de bST. Effect of recombinant bovine somatotropin (bst) on milk production of Saanen and Anglo-Nnubian goats. Abstract: This work was carried out at Embrapa Caprinos, in Sobral, Ceará, to evaluate the effect of recombinant bovine somatotropin (bST) on milk production of Saanen ang Anglo-Nubian goats fed two levels of concentrate. Thirty animals, between the second and the fouth parturition order, were divided into two groups according with the the amount of concentrate: 1 kg/animal/day and 1.25 kg/animal/day. Each group was splited in two treatments, being fed 0 mg/kg BW and 3mg/kg BW of bST. Statistical analysis were done by GLM procedure, by utilizing a model which included the fixed effects of breeds, levels of concentrate, interactions of breeds and levels of concentrate, bST and its interactions, and the variable days of lactation (linear and squared effects). It was found effect (P<0.01) of breed, levels of concentrate and application of bST on milk production, being signifficant (P<0.01) only the interaction breed x levels of concentrate. Milk production was higher (P<0.05) for Saanen in relation to Anglo-Nubian only in the treatment with the lowest level of concentrate. For Anglo-nubian the amount of concentrate influenced (P<0.05) milk production. Milk production increased (P<0.05) with bST application from 1.73 kg/animal/day to 2.04 kg/animal/day. It was concluded that milk production in the studyed breeds can be improved with BST application

Cultivo de abóbora do tipo japonesa por semeio direto e por transplante de mudas em diferentes sistemas de plantio.

Esse trabalho teve por objetivo avaliar duas cultivares de abóbora tipo japonesa (Jabras e Fortuna) em três sistemas de plantio (sistema de plantio direto - SPD, Sistema de plantio convencional com preparo do solo SPC e dois métodos de plantio (semeio direto no local definitivo e transplante de mudas produzidas em bandeijas.Suplemento. Trabalho apresentado no 52. Congresso Brasileiro de Olericultura, Salvador, 2012

Assessment of carotenoids in pumpkins after different home cooking conditions.

The aim of this study was to assess the total carotenoid, a- and B-carotene, and 9 and 13-Z- B-carotene isomer contents in C. moschata after different cooking processes