scholarly journals Cretaceous chimera – an unusual 100-million-year old neuropteran larva from the “experimental phase” of insect evolution

2019 ◽  
Vol 12 (1) ◽  
pp. 1 ◽  
Author(s):  
Carolin Haug ◽  
Andrés Fabián Herrera-Flórez ◽  
Patrick Müller ◽  
Joachim T. Haug
Author(s):  
Afonso Ferreira Miguel Junior ◽  
Luiz Fernando Santos de Vasconcelos ◽  
Celina Kakitani ◽  
césar yutaka ofuchi ◽  
Moisés Marcelino Neto ◽  
...  

AI ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 261-273
Author(s):  
Mario Manzo ◽  
Simone Pellino

COVID-19 has been a great challenge for humanity since the year 2020. The whole world has made a huge effort to find an effective vaccine in order to save those not yet infected. The alternative solution is early diagnosis, carried out through real-time polymerase chain reaction (RT-PCR) tests or thorax Computer Tomography (CT) scan images. Deep learning algorithms, specifically convolutional neural networks, represent a methodology for image analysis. They optimize the classification design task, which is essential for an automatic approach with different types of images, including medical. In this paper, we adopt a pretrained deep convolutional neural network architecture in order to diagnose COVID-19 disease from CT images. Our idea is inspired by what the whole of humanity is achieving, as the set of multiple contributions is better than any single one for the fight against the pandemic. First, we adapt, and subsequently retrain for our assumption, some neural architectures that have been adopted in other application domains. Secondly, we combine the knowledge extracted from images by the neural architectures in an ensemble classification context. Our experimental phase is performed on a CT image dataset, and the results obtained show the effectiveness of the proposed approach with respect to the state-of-the-art competitors.


1983 ◽  
Vol 27 (12) ◽  
pp. 7831-7834 ◽  
Author(s):  
K. C. Woo ◽  
Helen Mertwoy ◽  
J. E. Fischer ◽  
W. A. Kamitakahara ◽  
D. S. Robinson

1970 ◽  
Vol 92 (3) ◽  
pp. 639-652 ◽  
Author(s):  
C. E. Smeltzer ◽  
M. E. Gulden ◽  
W. A. Compton

This is a two-part paper, which stresses the materials science approach to understanding dust erosion mechanisms. The first part is an experimental phase, studying the effects upon solid-particle erosion, of such material and environmental variables as target alloy composition and heat-treat condition; dust particle velocity, size, concentration, velocity, and kinetic energy; carrier-gas true temperature and impingement angle. All test variables and their limits were chosen to simulate the range of engineering conditions and erosive environments encountered in helicopter turbine service. Actual erosion data are compared with erosion levels predicted by existing theories on particulate erosion. The second part is a diagnostic phase, programmed to detect and study visible phenomena associated with the erosion processes, using high-magnification electron microscopy. Phenomenological evidence obtained from the erosion surfaces and erosion products are used to define probable physical models of the erosion mechanisms.


2005 ◽  
Vol 4 (2) ◽  
pp. 131-141 ◽  
Author(s):  
Barbara Pawlak ◽  
Richard Gordon

PET (positron emission tomography) scans are still in the experimental phase, as one of the newest breast cancer diagnostic techniques. There are two traditional approaches to the computation of images from data collected in PET. In the first, standard CT (computed tomography) algorithms are used on rays designated by pairs of detectors receiving coincidence events. The problem generated by this approach is that generally only the mean can be used by such algorithms. With the relatively small numbers of events in PET, and with Poisson statistics for which variance equals the mean, the noise sensivity of standard CT algorithms becomes limiting. This is exasperated further by 3D imaging with cylindrical arrays of detectors. Statistical CT algorithms take the variance into account. As in the list-mode approach, we consider each coincidence event individually. However, we estimate the location of the annihilation event that caused each coincidence event, one by one, based on the previously assigned location of events processed earlier. The estimated annihilation locations form the image. To accomplish this, we construct a probability distribution along each coincidence line. This is generated from previous annihilation points by density estimation. In this paper we present our density estimation approach to positron emission tomography. Nonparametric methods of density estimation are overviewed followed by numerical examples. Our goal here is to determine which density estimation approach is most suitable for PET.


1991 ◽  
Vol 177 ◽  
pp. 169-186 ◽  
Author(s):  
D. Mondieig ◽  
J.R. Housty ◽  
Y. Haget ◽  
M.A. Cuevas-Diarte ◽  
H.A.J. Oonk

Author(s):  
Luiz Fernando Santos de Vasconcelos ◽  
Thales Sirino ◽  
Celina Kakitani ◽  
Moisés Marcelino Neto ◽  
Rigoberto Morales ◽  
...  

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2521 ◽  
Author(s):  
Miquel Domingo-Espin ◽  
J. Antonio Travieso-Rodriguez ◽  
Ramon Jerez-Mesa ◽  
Jordi Lluma-Fuentes

In this paper, the fatigue response of fused filament fabrication (FFF) Acrylonitrile butadiene styrene (ABS) parts is studied. Different building parameters (layer height, nozzle diameter, infill density, and printing speed) were chosen to study their influence on the lifespan of cylindrical specimens according to a design of experiments (DOE) using the Taguchi methodology. The same DOE was applied on two different specimen sets using two different infill patterns—rectilinear and honeycomb. The results show that the infill density is the most important parameter for both of the studied patterns. The specimens manufactured with the honeycomb pattern show longer lifespans. The best parameter set associated to that infill was chosen for a second experimental phase, in which the specimens were tested under different maximum bending stresses so as to construct the Wöhler curve associated with this 3D printing configuration. The results of this study are useful to design and manufacture ABS end-use parts that are expected to work under oscillating periodic loads.


Author(s):  
Rondolf J. Moreno ◽  
Anthony Pollman ◽  
Dragoslav Grbovic

Military systems greatly depend on the availability of energy. This energy comes mostly in the form of burning fuel in order to produce mechanical work or producing electricity. The ability to extract the most out of these systems aligns with the current focus of energy efficiency, not only in the military, but in society at large. In this research, an infrared camera was used to create an infrared map to infer temperature differences on a gasoline-powered generator at steady state operations. These temperature differences were inputted into an experimental phase during which a digitally-controlled hot plate, water block, variable resistor, and digital acquisitions system were used to measure current output from a single TEG for loads of 1, 10, and 100 Ω, respectively. Data were analyzed and the correlation coefficients determined. These coefficients were modeled a single module and then various array configurations for TEGs in COMSOL. Using the findings, a single commercial 56 mm by 56 mm Be2Te3 TEG can yield 0.72 W of power. Simple calculations yield 72 W of power when 100 modules are joined in 10 sets coupled in parallel with each set containing 10 modules in coupled in series. This would require 560 mm by 560 mm or approximately 2 ft. by 2 ft. of system space to be covered.


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