A rotorcraft in-flight ice detection framework using computational aeroacoustics and Bayesian neural networks

This work develops a novel ice detection framework specifically suitable for rotorcraft using computational aeroacoustics and Bayesian neural networks. In an offline phase of the work, the acoustic signature of glaze and rime ice shapes on an oscillating wing are computed. In addition, the aerodynamic performance indicators corresponding to the ice shapes are also monitored. These performance indicators include the lift, drag, and moment coefficients. A Bayesian neural network is subsequently trained using projected Stein variational gradient descent to create a mapping from the acoustic signature generated by the iced wings to predict their performance indicators along with quantified uncertainty that is highly important for time- and safety-critical decision-making scenarios. While the training is carried out fully offline, usage of the Bayesian neural network to make predictions can be conducted rapidly online allowing for an ice detection system that can be used in real time and in-flight

Dynamic extensions of batch systems with cloud resources

Compute clusters use Portable Batch Systems (PBS) to distribute workload among individual cluster machines. To extend standard batch systems to Cloud infrastructures, a new service monitors the number of queued jobs and keeps track of the price of available resources. This meta-scheduler dynamically adapts the number of Cloud worker nodes according to the requirement profile. Two different worker node topologies are presented and tested on the Amazon EC2 Cloud service

NTRFinder: a software tool to find nested tandem repeats

We introduce the software tool NTRFinder to search for a complex repetitive structure in DNA we call a nested tandem repeat (NTR). An NTR is a recurrence of two or more distinct tandem motifs interspersed with each other. We propose that NTRs can be used as phylogenetic and population markers. We have tested our algorithm on both real and simulated data, and present some real NTRs of interest. NTRFinder can be downloaded from http://www.maths.otago.ac.nz/~aamatroud/

Parallelized Incomplete Poisson Preconditioner in Cloth Simulation

Efficient cloth simulation is an important problem for interactive applications that involve virtual humans, such as computer games. A common aspect of many methods that have been developed to simulate cloth is a linear system of equations, which is commonly solved using conjugate gradient or multi-grid approaches. In this paper, we introduce to the computer gaming community a recently proposed preconditioner, the incomplete Poisson preconditioner, for conjugate gradient solvers. We show that the parallelized incomplete Poisson preconditioner (PIPP) performs as well as the current state-of-the-art preconditioners, while being much more amenable to standard thread-level parallelism. We demonstrate our results on an 8-core Apple* Mac* Pro and a 32-core code name Emerald Ridge system

Impact of perioperative infarcts after cardiac surgery

Background and Purpose: Brain injury after cardiac surgery is a serious concern for patients and their families. The purpose of this study was to use 3-T fluid attenuated inversion recovery MRI to characterize new and preexisting cerebral ischemic lesions in patients undergoing cardiac surgery and to test whether the accumulation of new ischemic lesions adversely affects cognition. Methods: Digital comparison of before and after fluid attenuated inversion recovery MRI images was performed for 77 cardiac surgery patients. The burden of preexisting versus new ischemic lesions was quantified and compared with the results of baseline and postoperative neuropsychological testing. Results: After surgery, new lesions were identified in 31% of patients, averaging 0.5 lesions per patient (67 mm3 [0.004%] of brain tissue). Patients with preexisting lesions were 10× more likely to receive new lesions after surgery than patients without preexisting lesions. Preexisting ischemic lesions were observed in 64% of patients, averaging 19.4 lesions (1542 mm3 [0.1%] of brain tissue). New lesions in the left hemisphere were significantly smaller and more numerous (29 lesions; median volume, 44 mm3; volume range, 5–404 mm3) than those on the right (10 lesions; median volume, 128 mm3; volume range, 13–1383 mm3), which is consistent with a cardioembolic source of particulate emboli. Overall, the incidence of postoperative cognitive decline was 46% and was independent of whether new lesions were present. Conclusions: New lesions after cardiac surgery added a small (≈4%) contribution to the burden of preexisting cerebrovascular disease and did not seem to affect cognitive function

Production and reliability oriented SOFC cell and stack design

The paper presents an innovative development methodology for a production and reliability oriented SOFC cell and stack design aiming at improving the stacks robustness, manufacturability, efficiency and cost. Multi-physics models allowed a probabilistic approach to consider statistical variations in production, material and operating parameters for the optimization phase. A methodology for 3D description of spatial distribution of material properties based on a random field models was developed and validated by experiments. Homogenized material models on multiple levels of the SOFC stack were established. The probabilistic models were related to the experimentally obtained properties of base materials to establish a statistical relationship between the material properties and the most relevant load effects. Software algorithms for meta models that allow the detection of relationships between input and output parameters and to perform a sensitivity analysis were developed and implemented. The capabilities of the methodology is illustrated on two practical cases

Características físicas pós-colheita de plátano consorciados com espécies arbóreas.

O cultivo de musáceas consorciado com palmeiras e árvores manejadas, sistema silvibananeiro, constitui-se em um típico sistema agroflorestal (SAF). Em regiões de fronteira agrícola, como o norte de Mato Grosso, selecionar espécies arbóreas e variedades de bananas e plátanos para este cultivo pode contribuir para a adoção de sistemas de produção conservacionistas, como os SAFs. Assim, objetivou-se avaliar o efeito de espécies arbóreas sobre carcaterísticas físicas de frutos de plátano (banana-da-terra). Para tal, um experimento de campo foi implantado em Sinop-MT, em DBC com cinco tratamentos e três repetições. Quatro tratamentos foram consórcios agroflorestais de uma espécie arbórea (acácia, eucalipto, casuarina e taxi-branco) e o plátano var. ?D?Angola?. O quinto tratamento foi a monocultura do plátano, em fila dupla e espaçamento de 4,5 m x 2,0 m x 1,6 m. Os consórcios tiveram arranjo em aleias, com as árvores no espaçamento 4,0 m x 2,0 m e os plátanos no centro das entrelinhas alternadas das árvores, em espaçamento de 2 m entre si. As segundas pencas de cachos de três plantas por repetição foram colhidas no estádio 1 de maturação. Ao atingirem o estádio 7 avaliaram-se: massa, comprimento e diâmetro de frutos; massa da casca e da polpa; diâmetro da polpa; espessura da casca e rendimento de polpa. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey (p≤0,05). Houve diferença significativa entre os tratamentos para comprimento e massa dos frutos e massa da polpa. Em monocultura foram obtidos os frutos mais compridos (296,9 mm) e os menores foram observados no consórcio com casuarina (220,5 mm). As maiores massas de fruto foram observadas nos tratamentos monocultura (301, 5 g) e consórcio com taxi-branco (278,3 g) e a menor foi observada no consórcio com casuarina (182,8 g). Os resultados de massa da polpa foram semelhantes aos de massa de frutos, sendo as maiores massas da polpa observadas em monocultura (227,5 g), consórcio com taxi-branco (219,7 g) e com eucalipto (163,7 g) e a menor para o consórcio com casuarina (136, 6 g). Não houve diferença para diâmetro dos frutos (41,4 mm) e da polpa (36,6 mm), espessura de casca (2,4 mm) e rendimento (75,6%). Algumas características físicas dos frutos de plátano ?D?Angola? são afetadas em função da espécie arbórea do sistema silvibananeiro. Na comparação com a monocultura, o taxi-branco foi a espécies que menos interferiu na qualidade física dos frutos de plátano D?Angola

Measurements of branching fraction ratios and CP-asymmetries in suppressed B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^- decays

We report the first reconstruction in hadron collisions of the suppressed decays B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^-, sensitive to the CKM phase gamma, using data from 7 fb^-1 of integrated luminosity collected by the CDF II detector at the Tevatron collider. We reconstruct a signal for the B^- -> D(-> K^+ pi^-)K^- suppressed mode with a significance of 3.2 standard deviations, and measure the ratios of the suppressed to favored branching fractions R(K) = [22.0 \pm 8.6(stat)\pm 2.6(syst)]\times 10^-3, R^+(K) = [42.6\pm 13.7(stat)\pm 2.8(syst)]\times 10^-3, R^-(K)= [3.8\pm 10.3(stat)\pm 2.7(syst]\times 10^-3, as well as the direct CP-violating asymmetry A(K) = -0.82\pm 0.44(stat)\pm 0.09(syst) of this mode. Corresponding quantities for B^- -> D(-> K^+ pi^-)pi^- decay are also reported.Comment: 8 pages, 1 figure, accepted by Phys.Rev.D Rapid Communications for Publicatio

Combined search for the quarks of a sequential fourth generation

Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions.Comment: Replaced with published version. Added journal reference and DO