Towards intelligent CFRP composite machining: surface analysis methods and statistical data analysis of machined fibre laminate surfaces

Many carbon fibre reinforced polymer composite parts need to be edged trimmed before use to ensure both geometry and mechanical performance of the part edge matches the design intent. Measurement and control of machining induced surface damage of composite material is key to ensuring the part retains its strength and fatigue properties. Typically, the overall surface roughness of the machined face is taken to be an indicator of the amount of damage to the surface, and it is important that the measurement and prediction of surface roughness is completed reliably. It is known that the surface damage is heavily dependent on the fibre orientation of the composite and cutting tool edge condition. This research has developed a new ply-by-ply surface roughness measurement methods using optical focus variation surface analysis and image segmentation for calculating areal surface roughness parameters of a machined carbon fibre composite laminate. Machining experiments have been completed using a polycrystalline diamond edge trimming tool at increasing levels of cutting edge radius. Optical surface measurement and µ-CT scanning have been used to assess machining induced surface and sub-surface defects on individual fibre orientations. Statistical analysis has been used to assess the significance of machining parameters on Sa (arithmetic mean height of area) and Sv (areal magnitude of maximum valley depth) areal roughness parameters, on both overall roughness and ply-by-ply fibre orientations. Empirical models have been developed to predict surface roughness parameters using statistical methods. It has been shown that cutting edge degradation, fibre orientation and feed rate will significantly affect the cutting mechanism, machining induced surface defects and surface roughness parameters

1/m_b^2 correction to the left-right lepton polarization asymmetry in the decay B -> X_s mu^+ mu^-

Using a known result by Falk et al. for the 1/m_b^2 correction to the dilepton invariant mass spectrum in the decay B \rightarrow X_s \mu^+ \mu^-, we calculate the 1/m_b^2 correction to the left-right muon polarization asymmetry in this decay. Employing an up-to-date range of values for the non-perturbative parameter \lambda_1, we find that the correction is much smaller than it should have been expected from the previous work by Falk et al.Comment: 8 pages, 2 figures included. Uses epsf.sty and rotate.sty. To appear in Physical Review D. The complete postscript file is also available from URL ftp://feynman.t30.physik.tu-muenchen.de/pub/preprints/ tum_t31_98_96.ps.g

Accounting for Equity Considerations in Cost-Effectiveness Analysis : A Systematic Review of Rotavirus Vaccine in Low- and Middle-Income Countries

Additional file 3: Appendix C. Full data table of results

Two photon decays of heavy vector mesons, B∗→BγγB^{*}\to B\gamma \gamma,D∗→DγγD^{*}\to D\gamma \gamma, and the possible determination of the gB∗(D∗)B(D)πg_{B^{*}(D^{*})B(D)\pi} and gB∗0B0γg_{{B^{*}}^0B^0\gamma} couplings

We study the novel decays $B^{*}\to B\gamma\gamma$ and $D^{*}\to D\gamma \gamma$ using the framework of the Heavy Meson Chiral Lagrangian (HM$\chi$L) to leading order in chiral perturbation theory. The branching ratios of these decays are expressed in terms of the strong $g_{B^{*}(D^{*})B(D)\pi}$ and the electromagnetic $g_{B^{*}(D^*)B(D)\gamma}$ couplings, thus providing a possible tool for their determination. In the charm case, using the experimentally determined ratios $({D^*}^{0,+}\to D\pi)/({D^*}^{0,+}\to D\gamma),$ we are able to express the branching ratio as a function of the strong coupling only. We thus find $1.6\times 10^{-6}<{\rm Br} ({D^{*}}^{0}\to D^0\gamma\gamma)<3.3\times 10^{-5}$ for $0.25<g<1,$ where $g$ is the strong coupling of HM$\chi$L. In the beauty sector, the ${\rm Br}({B^{*}}^{0} \to B^0 \gamma\gamma)$ which we estimate to be in the $10^{-7}-10^{-5}$ range is a function of both $g_{B^{*}B\pi}$ and $g_{B^{*}B\gamma}.$ Its behaviour does not afford an unambiguous determination of these couplings except for the region of high $g$ values like $g>0.6.$ The expected two-photon differential distributions are presented for both ${B^{*}}^{0} \to B^0 \gamma\gamma$ and ${D^{*}}^{0}\to D^0\gamma\gamma,$ for different values of the couplings involved.Comment: 22 pages, LaTeX, 5 ps-figures (uses subfigure.sty). Accepted by Phys. Rev.

Cadophora margaritata sp. nov. and other fungi associated with the longhorn beetles Anoplophora glabripennis and Saperda carcharias in Finland

Symbiosis with microbes is crucial for survival and development of wood-inhabiting longhorn beetles (Coleoptera: Cerambycidae). Thus, knowledge of the endemic fungal associates of insects would facilitate risk assessment in cases where a new invasive pest occupies the same ecological niche. However, the diversity of fungi associated with insects remains poorly understood. The aim of this study was to investigate fungi associated with the native large poplar longhorn beetle (Saperda carcharias) and the recently introduced Asian longhorn beetle (Anoplophora glabripennis) infesting hardwood trees in Finland. We studied the cultivable fungal associates obtained from Populus tremula colonised by S. carcharias, and Betula pendula and Salix caprea infested by A. glabripennis, and compared these to the samples collected from intact wood material. This study detected a number of plant pathogenic and saprotrophic fungi, and species with known potential for enzymatic degradation of wood components. Phylogenetic analyses of the most commonly encountered fungi isolated from the longhorn beetles revealed an association with fungi residing in the Cadophora-Mollisia species complex. A commonly encountered fungus was Cadophora spadicis, a recently described fungus associated with wood-decay. In addition, a novel species of Cadophora, for which the name Cadophora margaritata sp. nov. is provided, was isolated from the colonised wood.Peer reviewe

Disorders of Consciousness

Disorders of Consciousness are a big challenge for the entire process of rehabilitation: assessment, diagnosis, pharmacological, and rehabilitation programs, including conventional treatments and the use of new technologies