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Impact of the Objective Function on the Construction of Internal Grids of Wind Farms Using Genetic Algorithm

Open Journal of Civil Engineering 2016年第5期6卷 705-721页

作者： Paulo R. Monteiro Duailibe Thiago T. Borges André F. Schiochet Carlos Alberto P. Soares Programa de Pós-Graduaç &atilde o em engenharia Civil Universidade Federal Fluminenese Niterói Brasil departamento de engenharia Elétrica Universidade Federal Fluminense Niterói Brasil Petróleo Brasileiro S/A Rio de Janeiro Brasil

The macro complex of the construction industry is energy intensive. Solutions that enable the supply of this demand while meeting the principles of sustainability are needed. The construction of wind farms has been a strategy employed by many countries to produce clean energy. An increase in the construction of wind farms has also been witnessed in Brazil. This calls for different activities, such as the design and construction of infrastructure. This article focuses on the design of internal medium voltage distribution grids for wind farms. The purpose is to find a radial configuration that connects a set of wind generators to the substation, in an optimum way, minimizing operational and construction costs, reducing loss and therefore contributing to sustainability. In large farms, the project design consists of a large combinatorial optimization problem, given the large number of possible configurations to be deployed. Finding the best solution for the internal grid depends on the criterion adopted for the objectives pursued. This article analyzes the different criteria that can be adopted in the design of the wind farm’s internal grid using a methodology based on genetic algorithm (GA). Its aim is to identify their influence on the solution of the problem and help decision-making by finding the most adequate criterion for the objectives pursued. The results show that the design of the internal grid is sensitive to the criteria adopted for the objective function. In addition, the degree of sensitivity is analyzed, showing that, in some cases, the solutions are not economically attractive and do not contribute to the reduction of losses.

关键词： Construction Infrastructure Wind Farm Infrastructure Collection Grid Network Configuration Genetic Algorithm

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New Approach to the Strain Analysis of Bragg Grating Sensors

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Photonic Sensors 2013年第1期3卷 74-80页

作者： José R. Alves da CUNHA Petrus Alcantara JR. Angela Santa BRJGIDA Gilvan BORGES Joāo Weyl COSTA Programa de Pós-Graduacāo em Fisica Universidade Federal do Pará Belém 66075-11 O Brazil Programa de Pós Graduacāo em engenharia Elétrica Universidade Federal do Pará Belém 66075-11 O Brazil

The response of an optical strain sensor based on the fiber Bragg grating is theoretically analyzed with a different approach of that found usually in the literature. In this model, geometrical changes suffered by the grating itself are taken into account. The results are compared with those from experiments, showing very good agreement.

关键词： Bragg grating sensor strain sensor Bragg wavelength

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Mechanical Characterization and Micro-Wear of FeB-Fe<sub>2</sub>B Layers on Boriding AISI D2 and AISI 4340 Steels

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Materials Sciences and Applications 2021年第7期12卷 330-344页

作者： Suellen Terroso de Mendonça Ferreira André Luiz Klemes Bacco Eduardo Mauro do Nascimento Carlos Maurício Lepienski Programa de Pós Graduaç &atilde o em engenharia e Materiais (PPGem) Universidade Tecnológica Federal do Paraná (UTFPR) Curitiba Brasil

The mechanical behavior and wear of the different hardened phases with bore-induced changes in AISI 4340 and AISI D2 steels were investigated. The hardness and modulus of elasticity were measured by nanoindentation and the values obtained for the layers in AISI D2 steel were 18 GPa and 325 GPa in the Fe2B boride phase, and 20 GPa and 360 GPa in the FeB boride phase, respectively. The AISI 4340 steel presented mainly the Fe2B phase. It was then possible to analyze the coefficient of friction obtained in the Fe2B phase of the steel AISI 4340 presented a range of 0.04 to 0.06. The AISI D2 steel presents two different phases in the boride layer being the coefficient of friction higher for the test in the FeB phase than for Fe2B, and the values vary from 0.065 to 0.075. These parameters were obtained with micro-wear tests. No adhesion failures were observed after the sliding tests in the interface of the two different boride layers. Cracks in the FeB phase after the sliding test were much more frequent.

关键词： Iron Boride Micro-Wear Test Mechanical Properties Boriding

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Chronic Meningococcemia

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Advances in Infectious Diseases 2016年第3期6卷 97-101页

作者： Rita Veiga Ferraz Filipa Ceia Raquel Duro Ana Cláudia Carvalho Paulo Andrade Susana Silva António Sarmento Infectious Diseases department Instituto de Inovacao e Investigacao em Saúde (I3S) Grupo de I&D em Nefrologia e Doencas Infeciosas Instituto Nacional de Engenharia Biomédica (INEB) Centro Hospitalar de Sao Joao Porto Portugal

Neisseria meningitidis is a gram-negative diplococcus which causes invasive disease. The most frequent clinical manifestations caused by infection with this pathogen, are meningitis and fulminant septic shock. More benign forms with a subacute or chronic pattern are rare but still can evolve to meningitis and have a fatal outcome. This entity is difficult to recognize, as febrile erythema with otherwise good general condition may simulate other diseases, namely viral infections. The authors reported the cases of two healthy young adults who were misdiagnosed with a viral infection. What they really had was a meningococcemia without meningitis presenting with mild and unspecific symptoms, such as, intermittent fever and a discrete macular rash. We pretend to highlight this rare, unspecific and heterogeneous symptoms which can provoke negligence of a potentially life threatening condition.

关键词： Neisseria meningitidis Meningococcal Disease Chronic Meningococemia

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Chemical Characterization of Auriferous Ores from the Brazilian State of Paraiba

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Journal of Minerals and Materials Characterization and Engineering 2015年第1期3卷 9-14页

作者： Marcelo Rodrigues do Nascimento Artur M.G.Lourenco Instituto Federal de Educacao Ciencia e Tecnologia da ParaibaLaboratorio de FlotacaoCampina GrandeBrazil Universidade Federal de Campina Grande Programa de Pos-Graduacao em Engenharia CivilCampina GrandeBrazil

One of the most important problems facing the gold industry is that the placer and free milling gold ores are almost terminating. Hence, the use of refractory ores has been increased during the recent years. In general, gold refractory ores occurs in various types of deposits associated with a range of minerals. Among the refractory ores, the sulfide type is the most common. The methodology employed in the mining process depends on the mode of occurrence of the ore and on the particle size, shape and degree of purity of the auriferous species. We have undertaken a mineralogical investigation of a representative sample of a complex gold mining ore collected in the municipality of Princesa Isabel, Paraiba, Brazil, using X-ray fluorescence spectrometry, X-ray diffractometry, infrared spectroscopy, inductively coupled plasma-atomic emission spectrometry and the Fire Assay. The results showed that the arsenic content of the ore was closely related to the gold content, and that the occurrence of “invisible gold” was associated primarily with pyrite and secondarily with arsenopyrite. The sulfur content of the ore was directly related to its refractoriness. It is concluded that gold mineralization in the study area is mainly of the gold-quartz-sulfide veins (lode gold), while the gold found in the mini-fractures of the deposits is probably associated with the hydrothermal processes that occurred in the region.

关键词： Auriferous Ore Chemical Characterization X-Ray Fluorescence Spectrometry X-Ray Diffractometry Inductively Coupled Plasma-Atomic emission Spectrometry

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Eutrophication Indexes Used as Fish Production Parameters in the Itaipu Reservoir(Brazil)

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Journal of Environmental Protection 2013年第7期4卷 151-178页

作者： Rinaldo Antonio Ribeiro Filho Julia Myriam de Almeida Pereira Miguel Petrere Junior Simone Frederigi Benassi engenharia de Pesca Universidade Estadual PaulistaRegistroBrazil Nucleo de Estudos de Ecossistemas Aquaticos Centro de Recursos Hidricos e Ecologia AplicadaEESCUniversidade de Sao PauloSao CarlosBrazil departamento de engenharia de Pesca e Aquicultura Universidade Federal de RondoniaRua da PazBrazil Programa de Pos Graduacao em Diversidade Bilogica e Conservacao Universidade Federal de Sao Carlos(UFSCar)SorocabaBrazil Programa de Pos Graduacao em Sustentabilidade em Ecossistemas Marinhos e Costeiros UNISANTASantosBrazil Divisao de Reservatorio(MARR.CD) Itaipu BinacionalFoz do IguacuBrazil

The knowledge of liminology can be applied in studies of trophic state indexes and morfoedaphic indexes as factors for determining the inference fish production in reservoirs. This work is based on the hypothesis of the trophic cascade relations, particularly related to bottom-up and top-down effect in Itaipu Reservoir (Brazil). Using the data available by Itaipu, from 1999 to 2004, analyzes of multiple regressions were accomplished to determine the relationships of the dependent and independent variables. We applied the trophic state indices (TSI) based on readings Secchi disk, total phosphorus and chlorophyll-a density for obtaining TSI medium. Morfoedaphic index was calculated based on the reading of the concentration of dissolved solids and the inference of fishing yield, from this index. The average results of the trophic state indices indicate an oligotrophic status for the entire reservoir as well as for the riverine, transition and lacustrine zones separately. The fish was yieldn Estimated by the relation with cyanobacteria concentration, and this was the best variable que explained this prediction. The use of the morfoedaphic index (MEI), with the recorded catch data, predictive models can generate que estimate the fishing yield in the Itaipu Reservoir. The relations of MEI with chlorophyll-a and water transparency que Indicate this index may be a good predicting factor for future fish captures.

关键词： Trophic Cascade Reservoir Limnology Biotic Community Fish Yield

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Historical Evolution of the Trophic and Limnological Relationships in the Itaipu Reservoir:Top-Down and Bottom-Up Effects upon Fish Production

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Advances in Bioscience and Biotechnology 2015年第6期6卷 390-407页

作者： Rinaldo Antonio Ribeiro Filho Miguel Petrere Junior Angelo Antonio Agostinho Simone Friderigi Benassi Julia Myriam de Almeida Pereira Edson Kiyoshi Okada Curso de engenharia de Pesca Universidade Estadual Paulista(Unesp)RegistroBrazil Programa de Pos Graduacao em Diversidade Bilogica e Conservacao Universidade Federal de Sao Carlos(UFSCar)SorocabaBrazil Programa de Pos Graduacao em Sustentabilidade em Ecossistemas Marinhos e Costeiros UNISANTASantosBrazil departamento de Biologia Nucleo de Pesquisas em LimnologiaIctiologia e AquiculturaUniversidade Estadual de MaringaParanaBrazil Divisao de Reservatorio(MARR.CD) Itaipu BinacionalFoz do IguaçuBrazil

Many experimental studies have contributed to the development of the theory of trophic chains in lacustrine habitats. They have revealed the important role played by fish, a subject that has been mostly ignored by limnological studies for the past few decades. Most of these studies were developed in Europe and in the United States. The general applicability of this theory has not yet been tested in subtropical and tropical habitats. In spite of controversies, the bottom-up: top-down trophic cascade hypotheses are the most adopted conceptual models. In this context, we examined if these hypotheses may be corroborated by data from the subtropical Itaipu Reservoir. A negative effect was verified between water transparency and total suspended solids. The detritivorous fish exerted a controlling effect on chlorophyll-a concentrations. Bottom-up effects were detected in four trophic levels, and top-down was detected in just one trophic level. The limnological variates influenced the chlorophyll-a concentration, which indicated that the lnTKN plus the effect of the quarter and the reservoir zone (and their interaction) were important.

关键词： Reservoir Trophic Cascade Top-Down Bottom-Up Limnology Biotic Community

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Use of Caffeine for the Evaluation of the Anthropic Influence over the Upper and Middle Iguaçu River Basins

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Journal of Water Resource and Protection 2022年第3期14卷 273-291页

作者： Bruna Scipioni Márcia Cristiane Kravetz Andrade Luis Otávio Miranda Peixoto Alinne Mizukawa Tais Cristina Filippe Júlio César Rodrigues de Azevedo Programa de Pós-Graduaç &atilde o em engenharia de Recursos Hídricos e Ambiental Universidade Federal do Paraná Curitiba Brasil Universidade Tecnológica Federal do Paraná Curitiba Brasil

Many parameters are usually used as gauges to describe water quality worldwide, such as the concentrations of phosphorus, forms of nitrogen, dissolved oxygen (DO), among others. Though legislative limits for the concentrations of these substances are in place, such is not the case for caffeine. Caffeine is a pharmacologically active alkaloid, from the xanthine group, which can be used as a chemical tracer for anthropic influence over water resources. The objective of this study was to analyze the pollution indicators over the Igua?u River, one of the main rivers in Southern Brazil, through the examination of nutrients, DO and their correlations to caffeine. The water samples were collected from 10 sampling sites along the river course, unevenly spaced to better represent the different environmental scenarios present in its basin, extracted from 2014 to 2017. Caffeine was detected and quantified through high-efficiency liquid state chromatography. Results show that both nutrient and caffeine concentrations increased in intensely urbanized areas, specially from IG2 to IG5 sampling sites. Downstream from IG6 the contaminant concentrations decreased mainly due to higher river flows and lower population density. Caffeine was detected in 82% of the samples, indicating that most of the sampling sites were under anthropic influence.

关键词： Water Resources Water Quality Caffeine Urban Areas

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Sensory Evaluation of Winter Cereal Silage

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Journal of Chemistry and Chemical Engineering 2017年第3期11卷 102-106页

作者： Carlos Eugenio Fortes Teixeira Renato Serena Fontaneli Tecnico em mecdnica Engenharia Mecdnica--IFSul--Campus Passo Fundo Passo Fundo Brazil Agronomia/ppgAgro UPF Universidade de Passo Fundo Passo Fundo Brazil

Silage is aimed at conservation of green fodder, with minimal losses and that this kind of food, does not occur formation of toxic compounds for animals. Practical aspects become important when control ＂in loco＂, reflects management practiced in the property. There are different sensory evaluation techniques. The objective of this work was to study the applicability of the German system, now used in sensory evaluation of winter cereals （wheat silage and haylage oats）. For quantitative analysis of silage （pH） that was used potentiometer. In determining the qualitative analysis was used German method adapted. Relating them to sensory characteristics such as smell, texture and color of the fodder saved by assigning a score to each sensory： a ＂key＂ predetermined quality identification. For multiple comparisons for film types tested in oat silages BRS Centauro, the results show that the qualitative sensory attributes evaluated by rating corresponded to the quantitative attributes （pH） evaluated, with no difference. For multiple comparisons in the silages, for all test loads in both wheat genotypes results showed no difference between the qualitative evaluation （sensory） and quantitative.

关键词： Ensiling pre drying quality.

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Traffic Assignment Under State-dependent Travel Times

Traffic Assignment Under State-Dependent Travel Times

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2010 The 3rd International Conference on Power Electronics and Intelligent Transportation System (PEITS 2010)

作者： Felipe F.Cardoso Oriane Magela Neto Frederico R.B.Cruz Programa de Po′s-Graduao em engenharia Elétrica (PPGEE) Universidade Federal de Minas Gerais departamento de Estatística Universidade Federal de Minas Gerais

In this paper we investigate an M/G/c/c statedependent queueing network formula in the context of a System Optimum (SO) *** SO formulation is equivalent to a situation in which users cooperate with each other in order to minimize the overall travel cost,which is usually expressed in terms of travel *** from the classical travel cost formulas,the expression used here is not convex but ***,multiple solutions may be present for the SO,which justifies the use heuristic procedures such as the Differential Evolution (de) *** results from computational experiments with an de are given to attest for the efficiency of the approach and the quality of the solutions given.

关键词： System optimum,state-dependent,queues,queueing networks

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