The STARDAMP software: an assessment tool for wheel and rail damper efficiency

STARDAMP (Standardization of damping technologies for the reduction of railway noise) is a Franco-German research project within the DEUFRAKO framework that unites end users, manufacturers and research institutes. The target of STARDAMP is to support the transfer from R&D of wheel and rail dampers to their regular application. A software tool has been developed within STARDAMP that is dedicated to the prediction of the efficiency of wheel and rail dampers. The necessary input can be produced using relatively simple laboratory measurements. The rail response is assessed by combining track decay rates measured on a real track with decay rates measured in laboratory on a free rail that is equipped with dampers. The wheel response is calculated by using a finite element model of the wheel together with measured damping data. The tool is designed not only for the use by experts within the development of wheel and rail dampers. Indeed, a main goal of STARDAMP was to provide an easy-to-use tool to infrastructure managers and public authorities in order to help the decision making process regarding railway noise mitigation measures

Diversity of cicadomorpha (Hemiptera: Auchenorrhyncha) in Citrus orchards in Northeastern Argentina

Among phytophagous insects, the Cicadomorpha are important economically because they damage crops by sucking plant sap and by transmitting plant pathogens, such as Spiroplasma citri and Xylella fastidiosa to citrus. In Argentina little knowledge exists about this subject. The aim of this work was to study the diversity of Cicadomorpha associated with citrus orchards in Entre Ríos province, and their seasonal fluctuation in relation with climatic and phenological conditions. A total of 1,554 specimens belonging to 28 species of Cicadomorpha were collected with yellow sticky traps in sweet orange (Citrus × sinensis (L.) Osbeck) and tangerine (Citrus unshiu Marc) orchards. The Shannon index and the Simpson index suggested a similar trend in the distribution of the dominant species in both crops. In the orange orchard, Cicadomorpha populations increased in the summer coincidently with temperature increases. On the other hand, a significant increase in abundance during the winter months was coincident with increase of early sprouts of the citrus plants. Entre Ríos province represents a new distribution record for 13 species. Tangerine is a newly recorded host-plant for 16 species studied, and eight species are reported for the first time on 'Valencia Late' orange.Dentro de los insectos fitófagos, los Cicadomorpha tienen importancia económica por ocasionar daños por succión de savia en plantas y transmitir fitopatógenos como Spiroplasma citri y Xylella fastidiosa en cítricos. En Argentina es escaso el conocimiento acerca de esta temática. El objetivo del trabajo fue estudiar la diversidad de los Cicadomorpha asociados a cultivos cítricos en la provincia de Entre Ríos y su fluctuación estacional en relación con las condiciones climáticas y fenológicas. Los especímenes se colectaron con trampas adhesivas amarillas. En total fueron colectados 1554 especímenes pertenecientes a 28 especies de Cicadomorpha en cultivos de naranja dulce (Citrus × sinensis (L.) Osbeck) y mandarina (Citrus unshiu Marc). Los valores del índice de Shannon, sugieren una tendencia similar en la distribución de las especies dominantes en ambos cultivos. Esto también fue reflejado por el índice de Simpson. En el cultivo de naranja, los Cicadomorpha presentaron incrementos poblacionales en verano, coincidentes con los aumentos de la temperatura. Por otro lado, el incremento en la abundancia de especímenes durante los meses de invierno, fue coincidente con el aumento de brotes tempranos en los cítricos. La provincia de Entre Ríos fue citada como nuevo registro de distribución para 13 especies. El cultivo de mandarina es un nuevo registro de planta huésped para 16 especies estudiadas, y ocho especies son registradas por primera vez sobre naranja Valencia.Facultad de Ciencias Naturales y Muse

Structure of the specific combining ability between two species of Eucalyptus. II. A clustering approach and a multiplicative model

International audienceThe Eucalyptus breeding program of URPPI (a partnership between CIRAD-Fore t, Centre National de la Recherche Forestie re du Congo, and Unite dÕAforestation Industrielle du Congo) consists of a re- ciprocal recurrent selection scheme developed in the Congo between the two species Eucalyptus urophylla and Eucalyptus grandis. Two approaches are proposed in order to model and predict the speciÞc combining ability (SCA) between these species. The clustering ap- proach uses a simultaneous clustering procedure of the two species based on SCA and reveals heterotic groups coherent with the geographical origins of E. urophylla genotypes. The second approach uses a multiplicative model to partition the SCA into three multiplicative terms explaining 95% of the interactio

Yb-Yb correlations and crystal-field effects in the Kondo insulator YbB12 and its solid solutions

We have studied the effect of Lu substitution on the spin dynamics of the Kondo insulator YbB12 to clarify the origin of the spin-gap response previously observed at low temperature in this material. Inelastic neutron spectra have been measured in Yb1-xLuxB12 compounds for four Lu concentrations x = 0, 0.25, 0.90 and 1.0. The data indicate that the disruption of coherence on the Yb sublattice primarily affects the narrow peak structure occurring near 15-20 meV in pure YbB12, whereas the spin gap and the broad magnetic signal around 38 meV remain almost unaffected. It is inferred that the latter features reflect mainly local, single-site processes, and may be reminiscent of the inelastic magnetic response reported for mixed-valence intermetallic compounds. On the other hand, the lower component at 15 meV is most likely due to dynamic short-range magnetic correlations. The crystal-field splitting in YbB12 estimated from the Er3+ transitions measured in a Yb0.9Er0.1B12 sample, has the same order of magnitude as other relevant energy scales of the system and is thus likely to play a role in the form of the magnetic spectral response.Comment: 16 pages in pdf format, 9 figures. v. 2: coauthor list updated; extra details given in section 3.2 (pp. 6-7); one reference added; fig. 5 axis label change

Structure of the specific combining ability between two species of Eucalyptus. I. RAPD data

International audienceWithin the context of the reciprocal recurrent selection scheme developed in 1989 by CIRAD-Fore t on Eucalyptus, RAPD essays were performed to assess the genetic diversity in the two species E. urophylla and E. grandis. The molecular markers were split into two parts: the speciÞc markers (present with di¤erent fre- quencies in the two species) and the common markers (present with similar frequencies in the two species). The study analyses the structure of genetic diversity within and between the two species of Eucalyptus. Dif- ferent genetic distances are worked out for use in pre- diction equations of the individual tree trunk volume of hybrids at 38 months. Each distance is expressed as the sum of the general genetic distance and the speciÞc genetic distance. The general genetic distance based on the double presence plus the double absence of bands seems to be an interesting co-variate to use in a factor regression model. Through this model the distance calculated between species explains the general com- bining ability (GCA) and the speciÞc combining ability (SCA) of the phenotypic character with a global coe¦c- ient of determination of 81.6

Theory for Magnetic Anisotropy of Field-Induced Insulator-to-Metal Transition in Cubic Kondo Insulator YbB_{12}

Magnetization and energy gap of Kondo insulator YbB_{12} are calculated theoretically based on the previously proposed tight-binding model composed of Yb 5d$\epsilon$ and 4f $\Gamma_8$ orbitals. It is found that magnetization curves are almost isotropic, naturally expected from the cubic symmetry, but that the gap-closing field has an anisotropy: the gap closes faster for the field in (100) direction than in (110) and (111) directions, in accord with the experiments. This is qualitatively understood by considering the maximal eigenvalues of the total angular momentum operators projected on each direction of the magnetic field. But the numerical calculation based on the band model yields better agreement with the experiment.Comment: 4 pages, 4 figures, to appear in J. Phys. Soc. Jp

Fabrication and mechanical testing of a new sandwich structure with carbon fiber network core

The aim is the fabrication and mechanical testing of sandwich structures including a new core material known as fiber network sandwich materials. As fabrication norms for such a material do not exist as such, so the primary goal is to reproduce successfully fiber network sandwich specimens. Enhanced vibration testing diagnoses the quality of the fabrication process. These sandwich materials possess low structural strength as proved by the static tests (compression, bending), but the vibration test results give high damping values, making the material suitable for vibro-acoustic applications where structural strength is of secondary importance e.g., internal panelling of a helicopter

Diversity of cicadomorpha (Hemiptera: Auchenorrhyncha) in Citrus orchards in Northeastern Argentina

Among phytophagous insects, the Cicadomorpha are important economically because they damage crops by sucking plant sap and by transmitting plant pathogens, such as Spiroplasma citri and Xylella fastidiosa to citrus. In Argentina little knowledge exists about this subject. The aim of this work was to study the diversity of Cicadomorpha associated with citrus orchards in Entre Ríos province, and their seasonal fluctuation in relation with climatic and phenological conditions. A total of 1,554 specimens belonging to 28 species of Cicadomorpha were collected with yellow sticky traps in sweet orange (Citrus × sinensis (L.) Osbeck) and tangerine (Citrus unshiu Marc) orchards. The Shannon index and the Simpson index suggested a similar trend in the distribution of the dominant species in both crops. In the orange orchard, Cicadomorpha populations increased in the summer coincidently with temperature increases. On the other hand, a significant increase in abundance during the winter months was coincident with increase of early sprouts of the citrus plants. Entre Ríos province represents a new distribution record for 13 species. Tangerine is a newly recorded host-plant for 16 species studied, and eight species are reported for the first time on 'Valencia Late' orange.Dentro de los insectos fitófagos, los Cicadomorpha tienen importancia económica por ocasionar daños por succión de savia en plantas y transmitir fitopatógenos como Spiroplasma citri y Xylella fastidiosa en cítricos. En Argentina es escaso el conocimiento acerca de esta temática. El objetivo del trabajo fue estudiar la diversidad de los Cicadomorpha asociados a cultivos cítricos en la provincia de Entre Ríos y su fluctuación estacional en relación con las condiciones climáticas y fenológicas. Los especímenes se colectaron con trampas adhesivas amarillas. En total fueron colectados 1554 especímenes pertenecientes a 28 especies de Cicadomorpha en cultivos de naranja dulce (Citrus × sinensis (L.) Osbeck) y mandarina (Citrus unshiu Marc). Los valores del índice de Shannon, sugieren una tendencia similar en la distribución de las especies dominantes en ambos cultivos. Esto también fue reflejado por el índice de Simpson. En el cultivo de naranja, los Cicadomorpha presentaron incrementos poblacionales en verano, coincidentes con los aumentos de la temperatura. Por otro lado, el incremento en la abundancia de especímenes durante los meses de invierno, fue coincidente con el aumento de brotes tempranos en los cítricos. La provincia de Entre Ríos fue citada como nuevo registro de distribución para 13 especies. El cultivo de mandarina es un nuevo registro de planta huésped para 16 especies estudiadas, y ocho especies son registradas por primera vez sobre naranja Valencia.Facultad de Ciencias Naturales y Muse

Damage analysis and fracture toughness evaluation in a thin woven composite laminate under static tension using infrared thermography

This work deals with the issue of damage growth in thin woven composite laminates subjected to tensile loading. The conducted tensile tests were monitored on-line with an infrared camera, and tested specimens were analysed using Scanning Electron Microscopy (SEM). Combined with SEM micrographs, observation of heat source fields enabled us to assess the damage sequence. Transverse weft cracking was confirmed to be the main damage mode and fiber breakage was the final damage leading to failure. For cracks which induce little variation of specimen stiffness, the classic “Compliance method” could not be used to compute energy release rate. Hence, we present here a new procedure based on the estimation of heat source fields to calculate the energy release rate associated with transverse weft cracking. The results are then compared to those computed with a simple 3D inverse model of the heat diffusion problem and those presented in the literature