1,278 research outputs found

    Experimental evaluation of new one-chip solution for induction motor drives

    Get PDF
    The design of high performance induction motor drives is a complex task, and the every day compelling requirements in energy efficiency and performance assumes the motivation on finding a more integrated solution on implementing induction motor control. The main subjects of this paper are two: to discuss the IFOC one-chip solution and to explore the development of simple graphical applications in order to operate this control in a simple and effective way. Experimental results are presented to illustrate the main points of our paper

    Comparação da orientação institucional/ocupacional dos oficiais do Exército e da GNR

    Get PDF
    O presente trabalho pretende comparar as orientações profissionais dos oficiais do Exército e da GNR, à luz do modelo Institucional/Ocupacional de Moskos. Trata-se da comparação sobre quais serão os objectivos de ambas as organizações, enquanto entendidos pelos valores que orientam a actividade de um grupo de indivíduos: trabalhar segundo as leis do mercado ou efectuar um serviço à sociedade. Para este efeito são utilizados os resultados obtidos nas investigações realizadas por Sousa (1993) e Esteves (2006) a duas amostras representativas de ofi ciais dos Quadros Permanentes do Exército e da GNR. Os dados da investigação não confirmam a hipótese que sustentava que oficiais da GNR registariam orientações mais ocupacionais do que os oficiais do Exército, em virtude de um mais profundo relacionamento desta instituição com a sociedade civil. Ao contrário, os oficiais da GNR revelaram tendências mais próximas do pólo institucional que os seus colegas do Exército devido, fundamentalmente, a um sentimento mais forte de pertença à instituição. No entanto, revelaram também possuir uma visão mais burocrática da instituição. A coexistência destas orientações contraditórias parece, pois, sugerir que o modelo I/O não lida com pólos opostos de uma só dimensão mas sim com dimensões independentes, podendo um mesmo indivíduo expressar, em simultâneo, preocupações de carácter institucional e ocupacional

    Assessment of greenhouse gases (GHG) emissions from the tallow biodiesel production chain including land use change (LUC).

    Get PDF
    Economic uncertainties and environmental constraints regarding fossil fuels have encouraged initiatives for renewable energy sources and assessment of their life cycle impacts. Brazil ranks second worldwide in biodiesel production, despite the relatively recent organization of its national chain, marked by the creation of the National Program for Biodiesel Production and Use (PNPB). The Central-West region is responsible for the largest share of biodiesel production (44.4%) and the largest cattle slaughter (37.5%). In this scenario, beef tallow has great potential for expansion of biodiesel production, since it is a byproduct of the chain that, when not properly disposed, presents a considerable environmental burden. This work presents a method for assessing environmental performance that integrates life cycle assessment (LCA) with land use change (LUC) for analysis of the tallow biodiesel production chain. The results are given in terms of increment in annual greenhouse gases (GHG) emissions per hectare related to local tallow biodiesel. The system's boundary covers a representative major cattle farming area in Central-West Brazil. For the LCA segment of the method, five inventory allocations were considered: (i) without allocation, (ii) mass, (iii) market value, (iv) energy and (v) an ?average allocation?, calculated as the mean of mass, market value and energy. The last one is a novel approach proposed in this work, aggregating all the others, which separately result in under or over estimation of impacts. Using the ?average allocation?, the increment in annual GHG emission per hectare from tallow biodiesel production, is 43.2 kg CO2eq ha-1 y-1. This value is 17% less than the emission increment due to soybean biodiesel (50.2 kg CO2eq ha-1 y-1). LUC is responsible for 96% of the emission assessed, which demonstrates the importance of including LUC assessment in life cycle assessment of tallow biodiesel. According to the sensitivity analyses performed, changes from crop to pasture have superior environmental performance among the investigated options. Land use management is essential to preserve the remaining natural areas, making tallow biodiesel more sustainabl

    Uso de diferentes gonadotrofinas na indução de estro em cabras Toggenburg.

    Get PDF
    Use of different gonadotrophins to induce estrus in Toggenburg goats

    Effects of manipulations of player numbers vs. field dimensions on inter-individual coordination during small-sided games in youth football

    Get PDF
    The relative space per player formulated in small-sided and conditioned games can be manipulated either by promoting variations in player numbers or by modifying field dimensions. In this study we analysed how the same relative spaces per player, obtained through manipulations of player numbers and field dimensions, influenced inter-individual coordination. The positional data (GPS, 10 Hz) of 24 U-15 yrs performing in three different relative spaces per player (118, 133 and 152m2) was used. Inter-individual behavioural measures included: (i) effective relative space per player, (ii) radius of free movement; (iii) numerical relations inside each player’s relative space per player; and (iv) players’ spatial distribution variability. Magnitude-based inferences were used to analyse the practical significance of the selected variables. Results showed that manipulations of player numbers elicited more free space in the vicinity of each player. However, more advantageous numerical relations adjacent to each individual player and broader individual spatial distributions on field were observed during manipulations of field dimensions. These findings highlight the complex nature of performance behaviours captured by the co-adaptation of players to surrounding spatial constraints. Sport pedagogists should carefully evaluate the use of player numbers and field dimensions as strategies to simulate constraints of specific game contexts

    Cervix dilation and transcervical embryo recovery in cervical Santa Inês sheep.

    Get PDF
    Proceedings of the 28th Annual Meeting of the Brazilian Embryo Technology Society (SBTE), August, 2014, Natal, RN, Brazil. Abstracts

    Duration of estrus and time of ovulation in superovulated Santa Inês ewes.

    Get PDF
    Abstract: The aim of this study was to determine the intervals between sponge removal and the onset of estrus, sponge removal and the first detected ovulation, and onset of estrus and the first ovulation, and also to determine the duration of estrus, in superovulated Santa Inês ewes subjected to natural mating (NM) and AI. The trial was done in July and February at Cachoeiras de Macacu?Rio de Janeiro (22°27'S, 43°39'W). Fifteen non-pregnant Santa Inês ewes, age 3.4 ± 1.4 years, weighing 47.8 ± 6.3 kg, with 3.3 ± 0.4 body condition score (scale of 1 to 5), were randomly assigned to 2 groups. Both groups were superovulated using the same protocol and were mated in a crossover design by NM and laparoscopic AI. Estrus was synchronized using intravaginal sponges (60 mg of medroxyprogesterone acetate; Progespon®, Schering Plough Animal Health, São Paulo, Brazil) inserted (Day 0) and maintained for 6 days. On Day 5, the ewes received IM injections of 300 IU of eCG (Novormon®, Schering Plough Animal Health) and 0.0375 mg of cloprostenol (Prolise®, Tecnopec, São Paulo, Brazil). Twelve hours after sponge removal, 0.025 mg of gonadorelin acetate (Gestran®, Tecnopec) was administered IM. Superovulation started 60 h after sponge removal and consisted of 5 IU kg -1 of porcine FSH (pFSH; Pluset®, Hertape Calier, Minas Gerais, Brazil) IM in 6 decreasing doses (25, 25, 15, 15, 10, and 10%) at 12-h intervals. At the first pFSH dose, new sponges were inserted. At the fifth pFSH dose, 0.0375 mg of cloprostenol was administered IM and the sponges were removed. After the sponge removal, the NM group was exposed to rams twice per day for mating, until the end of estrus. In the AI group, estrus was detected using a teaser with the penis diverted. The females were permitted to be mounted twice per day until the end of estrus, and were inseminated with frozen-thawed semen 24 and 36 h after the end of superovulation. The follicular development and ovulation time were observed using real-time ultrasonography (8.0 MHz Pie Medical®, Aquila Vet, Tokyo, Japan) at 12-h intervals. For statistical analysis, a Student's t-test was performed (5% significance level) using the BioEstat program. Results are presented as mean ± standard deviation. The time from sponge removal to onset of estrus and the duration of estrus did not differ between NM and AI groups (31.79 ± 5.94 v. 25.25 ± 10.38 h and 29.89 ± 11.54 v. 26.66 ± 8.67 h, respectively). The time from sponge removal to ovulation and from onset of estrus to the first ovulation were shorter (P < 0.001) in the NM group (32.11 ± 12.72 v. 56.48 ± 15.39 h and 8.61 ± 5.99 v. 32.25 ± 18.57 h, respectively). The time from sponge removal to ovulation in July and February was 56.07 ± 7.27 versus 56.83 ± 20.72 in the AI group and 29.54 ± 0.56 versus 33.83 ± 19.02 in the NM group, respectively, suggesting that the season of the year in a tropical region did not influence the ovulation time for each treatment. Possibly, the mechanical stimulation induced by the contact of the penis with the vagina fornix and by the accessory sex glands fluids in mating hastened the ovulation time in the NM group. The service can shorten the time of ovulation

    Possíveis impactos do projeto: "Uso de sêmen resfriado e inseminação artificial em caprinos leiteiros na República de Cabo Verde".

    Get PDF
    Resumo - Este artigo procura discutir o contexto do projeto ?Uso de sêmen resfriado e inseminação artificial em caprinos leiteiros na República de Cabo Verde?, suas implicações no sistema de criação de caprinos leiteiros, bem como seu impacto nos planos social, ambiental e econômico. Possible impacts of the project: "use of chilled semen and artificial insemination in dairy goats on Cape Verde Republic?. Abstract - This article intent to discuss the aspects involved in the project ?Use of chilled semen and artificial insemination in dairy goats on Cape Verde Republic? their implications on dairy goats rearing and also, the social, the economic, and the environmental impacts.Anais do 15o. Simpósio Paranaense de Ovinocultura, 3o. Simpósio Paranaense de Caprinocultura, 3o. Simpósio Sul Brasileiro de Ovinos e Caprinos, Pato Branco, PR, out., 2011

    Avaliação do uso da prostaglandina na sincronização do estro associado ou não ao uso do hCG em cabras.

    Get PDF
    Resumo: O objetivo deste estudo foi avaliar a eficácia da sincronização do estro sobre os parâmetros ovarianos e comportamentais de cabras da raça Toggenburg. A administração da hCG no inicio do estro é capaz de antecipar a ovulação e promover um aumento no numero de ovulações. Estes resultados devem ser observados para estabelecimento momento ideal para a IA. [Evaluation of the use prostaglandin in synchronization the estrus associated or not the hCG in goats]
    corecore