Solving rank-constrained semidefinite programs in exact arithmetic

We consider the problem of minimizing a linear function over an affine section of the cone of positive semidefinite matrices, with the additional constraint that the feasible matrix has prescribed rank. When the rank constraint is active, this is a non-convex optimization problem, otherwise it is a semidefinite program. Both find numerous applications especially in systems control theory and combinatorial optimization, but even in more general contexts such as polynomial optimization or real algebra. While numerical algorithms exist for solving this problem, such as interior-point or Newton-like algorithms, in this paper we propose an approach based on symbolic computation. We design an exact algorithm for solving rank-constrained semidefinite programs, whose complexity is essentially quadratic on natural degree bounds associated to the given optimization problem: for subfamilies of the problem where the size of the feasible matrix is fixed, the complexity is polynomial in the number of variables. The algorithm works under assumptions on the input data: we prove that these assumptions are generically satisfied. We also implement it in Maple and discuss practical experiments.Comment: Published at ISSAC 2016. Extended version submitted to the Journal of Symbolic Computatio

Evaluation of wood basic density as an indirect measurement of the volume of wood raw material

The manufacturing process of wood agglomerate integrates distinct unit that transforms wood raw material into wood agglomerate. The yield of wood agglomerate produced is influenced by the density and the quality of the initial raw material. This work has compared two distinct methodologies aimed at defining the yield of the process through an indirect measurement at the precursor material. Samples (logs of differentiated sizes) were collected immediately at the industry entrance and several parameters were measured. The logs basic density and the moisture content was annotated, through analysis of the corresponding dry and wet mass. Log bark percentage has estimated also at the level of dry and wet basis. These parameters were used to determine the wood volume from different provenance and species in the beginning of the industrial process. The results indicated that wasn’t a great difference between the two different methods to determine the wood basic density and the wood volume in m3. Principal components analysis was used to investigate the differences between different provenances and different species for the wood basic density, and we conclude there is a great variability in wood basic density for the hardwood species than the observed for the softwood and there isn’t a great variability between different provenances. We study too the difference off wood moisture that could be occurring before the evaluation of wood basic density

Populational fluctuation and spatial distribution of Alphitobius diaperinus (Panzer) (Coleoptera; Tenebrionidae) in a poultry house, Cascavel, Parana state, Brazil.

Abstract Knowledge of the population fluctuation and spatial distribution of pests is fundamental for establishing an appropriate control method. The population fluctuation and spatial distribution of the Alphitobius diaperinus in a poultry house in Cascavel, in the state of Parana, Brazil, was studied between October, 2001 and October 2002. Larvae and adults of the lesser mealworm were sampled weekly using Arends tube traps (n = 22) for six consecutive flock grow-outs. The temperature of the litter and of the poultry house was measured at the same locations of the tube traps. Beetle numbers increased continuously throughout all the sampling dates (average 5,137 in the first week and 18,494 insects on the sixth week). Significantly greater numbers of larvae were collected than adults (1 to 20 times in 95% of the sampling points). There was no correlation between temperature and the number of larvae and adults collected, therefore no fluctuation was observed during the sampling period. The population growth was correlated to litter re-use. The highest temperatures were observed in deep litter. The spatial distribution of larvae and adults in the poultry house was heterogeneous during the whole period of evaluation. Results suggest that monitoring in poultry houses is necessary prior to adopting and evaluating control measures due to the great variability of the insect distribution in the poultry house. Keywords: lesser mealworm, poultry house, temperature, population dynamicbitstream/item/78871/1/ID-27879.pd

Caracterização de uma bebida alcoólica tradicional portuguesa, preparada com maceração de bagas de zimbro

The alcoholic drink called ‘aguardente de zimbro’ is a traditional Portuguese alcoholic beverage made by the people living around Serra da Estrela, using the maceration of juniper berries in different distillates like arbutus spirit, marc spirit and wine spirit. Traditionally homemade for own consumption in rural families, this beverage is now sold to tourists and promoted and included in the food patrimony of the region. However, there is a lack of technical and scientific information about this beverage. A first evaluation of this beverage is done in this work, based on its sensory and physicochemical characteristics. A few commercial samples, two homemade and another two samples of alcoholic beverages made with juniper were analysed in this work. Several analytical determinations, namely density, alcoholic strength, dry matter, total acidity, fixed acidity, volatile acidity, pH, chromatic characteristics, methanol, acetaldehyde, ethyl acetate, fusel alcohols and total antioxidant activity were done on the samples with the aim of characterising these Portuguese flavoured juniper spirits. The descriptive sensory analysis of these drinks was also done in order to find the more characteristic sensory attributes of the drink. The results show that under the label ‘aguardente de zimbro’ there are several drinks, with a yellow colour, but with several differences in physicochemical composition and sensory description. In fact, these drinks, with ethanol content from 37.7 to 48.3 % vol. present values of acidity from 25 to 1360 mg/L, pH from 3.91 to 5.89, dry matter 0.75 to 75.24 g/L and density from 0.9446 to 0.9770 g/cm3. Important differences were also observed in the chromatic characteristics, volatile composition and total antioxidant activity. Therefore, further research must be done in order to characterise this ‘traditional’ drink.elaborada a partir da maceração de bagas de zimbro em diferentes destilados nomeadamente aguardente bagaceira, aguardente vínica e aguardente de medronho. Esta bebida, que era tradicionalmente produzida para consumo próprio nas famílias rurais, é atualmente produzida industrialmente e vendida aos turistas como uma das imagens de marca dos produtos tradicionais da região. No entanto, há uma falta de informação técnica e científica sobre esta bebida. Neste trabalho é efetuada uma primeira caracterização desta bebida com base nas suas características sensoriais e físico-químicas. Neste trabalho foram analisadas algumas amostras comerciais, duas amostras caseiras e duas amostras de outras bebidas alcoólicas feitas com zimbro. Foram realizadas as seguintes determinações analíticas nas diferentes amostras recolhidas: densidade, teor alcoólico, matéria seca, acidez total, acidez fixa, acidez volátil, pH, características cromáticas, metanol, acetaldeído, acetato de etilo, álcoois superiores e atividade antioxidante total. Foi efetuada também, a caracterização sensorial descritiva dessas bebidas a fim de encontrar os atributos sensoriais mais característicos da bebida. Os resultados mostram que, sob a designação de “aguardente de zimbro” existem várias bebidas, com uma cor amarela, mas com algumas diferenças na composição físico-química e descrição sensorial. Efetivamente, estas bebidas, com um teor de etanol entre 37.7 e 48.3 % vol., apresentam valores de acidez de 25 a 1360 mg/L, pH de 3.91 a 5.89, matéria seca de 0.75 a 75.24 g/L e densidade de 0.9446 a 0.9770 g/cm3. Foram também verificadas diferenças importantes nas características cromáticas, composição volátil e atividade antioxidante total. É de referir, no entanto, que são necessários mais estudos de modo a aprofundar a caracterização desta bebida “tradicional”

Psilídeos no Brasil: 8 - Mastigimas anjosi (Hemiptera, Psylloidea), nova praga da Toona ciliata no Brasil.

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Avaliação da qualidade e rotulagem do mel: adequação à nova legislação

Só está disponível o resumo.Avaliação da qualidade e rotulagem do mel: adequação à nova legislação

Estudo da qualidade do mel comercializado na região de Castelo Branco

Comunicação oral da qual só está disponível o resumo.Estudo da qualidade do mel comercializado na região de Castelo Branco

Angra Neutrino Project: status and plans

We present the status and plans of the Angra Project, a new nuclear reactor neutrino oscillation experiment, proposed to be built in Brazil at the Angra dos Reis nuclear reactor complex. This experiment is aimed to measure theta_13, the last unknown of the three neutrino mixing angles. Combining a high luminosity design, very low background from cosmic rays and careful control of systematic errors at the 1% level, we propose a high sensitivity multi-detector experiment, able to reach a sensitivity to antineutrino disappearance down to sin^2(2*theta_13) = 0.006 in a three years running period, improving present limits constrained by the CHOOZ experiment by more than an order of magnitude.Comment: 2 pages, 1 figure, talk presented by J.C. Anjos ([email protected]) at NuFact05, 21-26 June 2005, Frascati, Ital

Microvespa-do-eucalipto-citriodora (Corymbia citriodora) - Epichrysocharis burwelli Schauff (Hymenoptera: Eulophidae).

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Primeiro registro da família Tachinidae como parasitóide de psilídeo (Hemiptera: Psylloidea).

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