Viscoelastic evaluation of biological soft tissue in crush process at subsonic level for anti-bird strike technology of airplane

Miniaturization and lightening of airplane are advanced to improve its economic efficiency, and the safety technology of airplane design becomes difficult while the accident of bird-strike is increasing year by year. Then a system of shock impact test by using airsoft rifle is developed to evaluate the design technology of anti-bird strike structure of airplane. The viscoelastic characteristics of specimen is evaluated by analyzing stress response using the modified Hertz contact theory and the wave equation at the moment when simple ball bullet is shot to specimen by the airsoft rifle. In the results of experiment, the obvious relationship is observed subjectively between quasi-static and impact responses of specimen. The evaluated viscoelastic relationship is applied to simulate the impact test by using LSDYNA with fundamental viscoelastic constitutive equation and the material parameters derived from the impact test, and the well similar behavior has been simulated by the constitutive equation. By using the developed technology here, the phantom imitating real bird will be developed as standard specimen for an anti-bird strike test in future

Orbit closures in the enhanced nilpotent cone

We study the orbits of $G=\mathrm{GL}(V)$ in the enhanced nilpotent cone $V\times\mathcal{N}$, where $\mathcal{N}$ is the variety of nilpotent endomorphisms of $V$. These orbits are parametrized by bipartitions of $n=\dim V$, and we prove that the closure ordering corresponds to a natural partial order on bipartitions. Moreover, we prove that the local intersection cohomology of the orbit closures is given by certain bipartition analogues of Kostka polynomials, defined by Shoji. Finally, we make a connection with Kato's exotic nilpotent cone in type C, proving that the closure ordering is the same, and conjecturing that the intersection cohomology is the same but with degrees doubled.Comment: 32 pages. Update (August 2010): There is an error in the proof of Theorem 4.7, in this version and the almost-identical published version. See the corrigendum arXiv:1008.1117 for independent proofs of later results that depend on that statemen

Glaucomatous vertical vessel density asymmetry of the temporal raphe detected with optical coherence tomography angiography.

Changes in retinal vasculature and ocular circulation may play an important role in the glaucoma development and progression. We evaluated the vertical asymmetry across the temporal raphe of the deep retinal layer vessel density, using swept-source optical coherence tomography angiography (SS-OCTA), and its relationship with the central visual field (VF) loss. Thirty-four eyes of 27 patients with open-angle glaucoma were included. SS-OCTA macular scanning was performed within a 3 × 3 mm (300 × 300 pixels) volume, centred on the fovea. The relationships between the vertical asymmetrical deep retinal vessel density reduction (ADRVD) across the temporal raphe and various ocular parameters were analysed. Twenty-two glaucomatous eyes with ADRVDs had central VF loss. Contrarily, ADRVDs were not found in any of the 12 eyes without central VF loss. Thirteen eyes (59.1%) with central VF loss had ADRVDs topographically corresponding to the central VF loss and macular ganglion cell complex thinning. The glaucomatous eyes with ADRVDs exhibited inferior rather than superior central VF loss (P = 0.032). Thus, ADRVD specifically indicates the glaucomatous central visual loss. Further analysis of ADRVD may improve our understanding on glaucoma pathogenesis, offering new treatment insights

Impacts of flashfloods on the cage farms in Kerala

Cage fish farmers across the coastal districts of Kerala suffered massive losses in the floods of August, 2018. The flooding and crop loss was also a setback to efforts of ICAR-CMFRI to popularize cage fish farming. The flood waters which completely washed many cages along with the cultured fishes meant loss was in terms of cage structure and nets, harvest ready fishes and juvenile fishes stocked for new cropping in cages. Around eight species of fish were being farmed in cages including the Asian seabass, pearl spot, red snapper, Caranx sp. and tilapia

Length-weight relationship and relative condition factor of Stolephorus commersonii (Lacepede, 1803) exploited along Kerala coast

The length-weight relationship and relative condition factor of Stolephorus commersonii was calculated to assess the significance of allometric factor and the well being. The study was carried out by using the data collected from ring seine and purse seine catches during the year 2010-2011. The length of species in catches ranged from 5 to 14.6 cm with a mean length of 9.24 ± 1.83 cm and the weight ranged from 1 to 25g with an average weight of 6.64 ± 3.96 g. Length-weight relationship calculated for male, female and pooled are W = 0.0070 L3.02, W = 0. 00756 L2.99 and W = 0. 0073 L3.006 respectively. The relative condition factor (Kn) estimated separately for male and female showed monthly fluctuation. The highest Kn values were observed in February and August and the lowest in June for both the sexes