1,128 research outputs found
Advances in Control of Onion Thrips (Thysanoptera: Thripidae) in Cabbage
Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), feeding injury results in discoloration and a rough texture on cabbage, Brassica oleracea capitata (L.), leaves, and damage may occur deep inside the head. It has become a key pest of cabbage in the United States and many other countries. Previous studies have indicated poor control using insecticides. The present study identified imidacloprid drenches and sprays of acetamiprid, dimethoate, spinosad, and imidacloprid as insecticides that performed better than the industry standard, lambda-cyhalothrin. However, additional tests with foliar sprays of dimethoate and acetamiprid indicated there was not an ideal crop stage (precupping, cupping, or postcupping) at which either insecticide could be applied for reliable control of T. tabaci, possibly because of multiple flights of thrips into the crop or the asynchrony of flights and susceptible crop stages. In tests in a commercial field, a soil drench of imidacloprid 4 wk after transplanting reduced the number of damaged leaves in the head by 32%, whereas five sprays of acetamiprid reduced damage by 51%. Combining both insecticide regimes reduced damage by 85%, but resulted in a very costly management program. Cabbage varieties varied considerably in susceptibility with some having negligible thrips injury, regardless of being treated with an insecticide. Planting date affected susceptibility of cabbage to some degree, but not as much as other tactics. Overall, these studies indicate that increased emphasis should be placed on breeding cabbages to be resistant to T. tabaci as the foundation for its managemen
Task-Projected Hyperdimensional Computing for Multi-Task Learning
Brain-inspired Hyperdimensional (HD) computing is an emerging technique for
cognitive tasks in the field of low-power design. As a fast-learning and
energy-efficient computational paradigm, HD computing has shown great success
in many real-world applications. However, an HD model incrementally trained on
multiple tasks suffers from the negative impacts of catastrophic forgetting.
The model forgets the knowledge learned from previous tasks and only focuses on
the current one. To the best of our knowledge, no study has been conducted to
investigate the feasibility of applying multi-task learning to HD computing. In
this paper, we propose Task-Projected Hyperdimensional Computing (TP-HDC) to
make the HD model simultaneously support multiple tasks by exploiting the
redundant dimensionality in the hyperspace. To mitigate the interferences
between different tasks, we project each task into a separate subspace for
learning. Compared with the baseline method, our approach efficiently utilizes
the unused capacity in the hyperspace and shows a 12.8% improvement in averaged
accuracy with negligible memory overhead.Comment: To be published in 16th International Conference on Artificial
Intelligence Applications and Innovation
Fermi Surface and Quasiparticle Excitations of overdoped Tl2Ba2CuO6+d by ARPES
The electronic structure of the high-T_c superconductor Tl2Ba2CuO6+d is
studied by ARPES. For a very overdoped Tc=30K sample, the Fermi surface
consists of a single large hole pocket centered at (pi,pi) and is approaching a
topological transition. Although a superconducting gap with d_x^2-y^2 symmetry
is tentatively identified, the quasiparticle evolution with momentum and
binding energy exhibits a marked departure from the behavior observed in under
and optimally doped cuprates. The relevance of these findings to scattering,
many-body, and quantum-critical phenomena is discussed.Comment: Revised manuscript, in press on PRL. A high-resolution version can be
found at
http://www.physics.ubc.ca/~quantmat/ARPES/PUBLICATIONS/Articles/Tl2201_LE.pdf
and related material at
http://www.physics.ubc.ca/~quantmat/ARPES/PUBLICATIONS/articles.htm
Resistant Starch and Starch Thermal Characteristics in Exotic Corn Lines Grown in Temperate and Tropical Environments
Corn as a food that is heated and cooled to allow starch retrogradation has higher levels of resistant starch (RS). Increasing the amount of RS can make corn an even healthier food and may be accomplished by breeding and selection, especially by using exotic germplasm. Sixty breeding lines of introgressed exotic germplasm backgrounds, selected for high yield, were grown in three tropical and temperate locations and analyzed for starch thermal characteristics and RS levels. Although actual values for all starch characteristics were within normal levels, most characteristics had significant genotypic effects, and all had significant location effects. Thermal properties of retrograded starch were more influenced by the environment than the thermal properties of raw starch, making retrograded starch traits more heritable than raw starch traits. This suggests that a breeding strategy based on retrograded starch traits will have a better chance of success than a breeding strategy based on raw starch traits. A significant genotype effect for RS levels indicates that genotypic selection to raise the level of RS and increase the healthful aspects of corn food should be successful. Significant location effects indicate that breeders using winter nurseries to accelerate their breeding progress need to be careful when making selections using RS data collected on seed grown in the tropics. A small but highly significant correlation between RS and some thermal characteristics, especially percentage of retrogradation, indicates that we may be able to select promising genotypes for RS selection based on our extensive database of thermal characteristics collected on a wide number of diverse corn lines
Predictors for failure of supraglottic superimposed high-frequency jet ventilation during endoscopic upper airway surgery in pediatric patients
Airway surgery in pediatric patients is challenging with regard to balancing surgical exposure with ventilation requirements, as during the procedure the airway must be shared between laryngologist and anesthetist. For endoscopic laryngeal surgery, different methods of ventilation are used, among others jet ventilation via a specifically adapted suspension laryngoscope using a dual jet stream(Supraglottic Superimposed High Frequency Jet ventilation, SSHFJV) (1).High BMI and a history of pulmonary pathology proved to be factors contributing to failing of SSHFJV in adult patients (2). However, factors influencing the failure of SSHFJV in pediatric patients have never been described yet
Accelerated Particle Swarm Optimization and Support Vector Machine for Business Optimization and Applications
Business optimization is becoming increasingly important because all business
activities aim to maximize the profit and performance of products and services,
under limited resources and appropriate constraints. Recent developments in
support vector machine and metaheuristics show many advantages of these
techniques. In particular, particle swarm optimization is now widely used in
solving tough optimization problems. In this paper, we use a combination of a
recently developed Accelerated PSO and a nonlinear support vector machine to
form a framework for solving business optimization problems. We first apply the
proposed APSO-SVM to production optimization, and then use it for income
prediction and project scheduling. We also carry out some parametric studies
and discuss the advantages of the proposed metaheuristic SVM.Comment: 12 page
Quantum Aspects of Semantic Analysis and Symbolic Artificial Intelligence
Modern approaches to semanic analysis if reformulated as Hilbert-space
problems reveal formal structures known from quantum mechanics. Similar
situation is found in distributed representations of cognitive structures
developed for the purposes of neural networks. We take a closer look at
similarites and differences between the above two fields and quantum
information theory.Comment: version accepted in J. Phys. A (Letter to the Editor
Relative Throughput of the Near-IR Science Instruments for the James Webb Space Telescope as Measured During Ground Testing the Integrated Science Instrument Module
Data were obtained for the purpose of measuring the relative throughput of the Near-IR Science Instruments (SIs) of the James Webb Space Telescope (JWST) as part of the second and third cryogenic-vacuum tests (CV2CV3) of the Integrated Science Instrument Module (ISIM) conducted at the Goddard Space Flight Center (GSFC) in 2014 and 20152016, at the beginning and end of the environmental test program, respectively. This Poster focuses on data obtained as part of the Initial Optical Baseline and as part of the Final Performance test -- two epochs that roughly bracket the CV3 test. The purpose of the test is to trend relative throughput to monitor for any potential changes from gross problems such as contamination or degradation of an optical element. Point source data were taken at a variety of wavelengths for NIRCam Module A and Module B, NIRSpec, NIRISS, Guider 1 and Guider 2 using the Laser Diode (LD) 1.06 micron, LD 1.55 micron, 2.1 micron LED and 3.5 micron LED, as well as for NIRCam Mod A and B and NIRISS using a tungsten source and the F277W, and F480M filters. Spectra were taken using the G140M, G235M, and G395M gratings for NIRSpec, the GRISMR grism for NIRCam Mod A and B and the GR150C grism for NIRISS. The results of these measurements are compared to what would be expected given the efficiency of each of the optical elements in each SI. Although these data were taken as a check against gross problems, they can also be used to provide the first relative throughput estimate for each SI through the various filters source wavelengths measured in their flight-like configurations
Geometric representations for minimalist grammars
We reformulate minimalist grammars as partial functions on term algebras for
strings and trees. Using filler/role bindings and tensor product
representations, we construct homomorphisms for these data structures into
geometric vector spaces. We prove that the structure-building functions as well
as simple processors for minimalist languages can be realized by piecewise
linear operators in representation space. We also propose harmony, i.e. the
distance of an intermediate processing step from the final well-formed state in
representation space, as a measure of processing complexity. Finally, we
illustrate our findings by means of two particular arithmetic and fractal
representations.Comment: 43 pages, 4 figure
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