1,050 research outputs found
Finite element for rotor/stator interactive forces in general engine dynamic simulation. Part 1: Development of bearing damper element
A general purpose squeeze-film damper interactive force element was developed, coded into a software package (module) and debugged. This software package was applied to nonliner dynamic analyses of some simple rotor systems. Results for pressure distributions show that the long bearing (end sealed) is a stronger bearing as compared to the short bearing as expected. Results of the nonlinear dynamic analysis, using a four degree of freedom simulation model, showed that the orbit of the rotating shaft increases nonlinearity to fill the bearing clearance as the unbalanced weight increases
Engine dynamic analysis with general nonlinear finite element codes. Part 2: Bearing element implementation overall numerical characteristics and benchmaking
Finite element codes are used in modelling rotor-bearing-stator structure common to the turbine industry. Engine dynamic simulation is used by developing strategies which enable the use of available finite element codes. benchmarking the elements developed are benchmarked by incorporation into a general purpose code (ADINA); the numerical characteristics of finite element type rotor-bearing-stator simulations are evaluated through the use of various types of explicit/implicit numerical integration operators. Improving the overall numerical efficiency of the procedure is improved
Contrasting multi-taxa diversity patterns between abandoned and non-intensively managed forests in the southern Dolomites
The abandonment of silvicultural activities can lead to changes in species richness and composition of biological communities, when compared to those found in managed forests. The aim of this study was to compare the multi-taxonomical diversity of two mature silver fir-beech-spruce forests in the southern Dolomites (Italy), corresponding to the European Union habitat type 9130. The two sites share similar ecological and structural characteristics, but differ in their recent management histories. In the last 50 years, one site underwent non-intensive management, while the other was left unmanaged and was included in a forest reserve. The species richness and composition of eight taxa were surveyed in the two sites between 2009 and 2011. The difference in mean species richness between the two forest management types was tested through permutation tests, while differences in species composition were tested by principal coordinates analysis and the permutational multivariate analysis of variance. Mean species richness of soil macrofungi, deadwood lichens, bark beetles, and longhorn beetles were significantly higher in the abandoned than in the non-intensively managed forests. Deadwood fungi and epiphytic lichens did not differ in mean species richness between the two study sites, while mean species richness of ground beetles and birds were higher in the non-intensively managed than in the abandoned forest. Significant differences in species composition between the two sites were found for all the taxa, except for longhorn beetles. These results indicate that improving forest landscape heterogeneity through the creation of a mosaic of abandoned and extensively managed forests should better fulfill the requirements of ecologically different taxa
Mercury's low‐degree geoid and topography controlled by insolation‐driven elastic deformation
©2015. American Geophysical UnionMercury experiences an uneven insolation that leads to significant latitudinal and longitudinal variations of its surface temperature. These variations, which are predominantly of spherical harmonic degrees 2 and 4, propagate to depth, imposing a long‐wavelength thermal perturbation throughout the mantle. We computed the accompanying density distribution and used it to calculate the mechanical and gravitational response of a spherical elastic shell overlying a quasi‐hydrostatic mantle. We then compared the resulting geoid and surface deformation at degrees 2 and 4 with Mercury's geoid and topography derived from the MErcury, Surface, Space ENvironment, GEochemistry, and Ranging spacecraft. More than 95% of the data can be accounted for if the thickness of the elastic lithosphere were between 110 and 180 km when the thermal anomaly was imposed. The obtained elastic thickness implies that Mercury became locked into its present 3:2 spin orbit resonance later than about 1 Gyr after planetary formation
Produção orgânica de café no Sítio Santa Cecília, em Glória de Dourados-MS
bitstream/item/66258/1/31284.pdfOrganizado por: Alberto Feiden, Milton Parron Padovan, Adalgiza Inês Campolim, Aurélio Vinícius Borsato, Ivo de Sá Motta, João Batista Catto, Tércio Jacques Fehlauer
Densidade e volume total de poros do solo cultivado com adubos verdes perenes consorciados com a bananeira em um sistema sob transição agroecológica em Mato Grosso do Sul.
bitstream/item/68859/1/041-carneiro-densidade.pdfPublicado também no Cadernos de Agroecologia, v. 7, n.2, 2012
Macro e microporosidade do solo cultivado com adubos verdes perenes consorciados com a bananeira em um sistema sob transição agroecológica em Mato Grosso do Sul.
bitstream/item/69053/1/066-carneiro-macro.pdfPublicado também no Cadernos de Agroecologia, v. 7, n.2, 2012
Biomassa microbiana do solo sob sistemas de manejo com diferentes coberturas vegetais.
bitstream/item/66226/1/31294.pdfOrganizado por: Alberto Feiden, Milton Parron Padovan, Adalgiza Inês Campolim, Aurélio Vinícius Borsato, Ivo de Sá Motta, João Batista Catto, Tércio Jacques Fehlaue
Phylogenetically Conditioned Possibilities of the Realization and of the Development of Complex Movements at the Age of 7 Years
Upon entering a school the seven-year olds ( 2 months) underwent a systematic, experimental,
specially programmed, eighteen-month-long transformational procedure.
The objective of the procedure was to develop the abilities and to observe the growth and
the development of children, both girls and boys. The data were processed by means of
discriminant analyses in each of the three control points. There was a total sample of
487 children. With regard to the phylogenetic characteristics of a human, it may be said
that the basic abilities connected with phylogenetic development may be clearly recognized,
precisely in such a way that children replicate this development throughout their
earliest childhood. Most probably, the basic ability was the ability to maintain a postural
balance, followed by the ability of movement control. Then came object manipulation
by upper extremities, followed by the significance of resistance to inertial forces
while moving, and ultimately the control of complex movements of the whole body
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