6,944 research outputs found
A new mix design method for steel fibre-reinforced, roller compacted and polymer modified bonded concrete overlays
Automation Laboratory Development Focusing on Industrial Hands-on Experience, Simulation Software, and Application Research Projects
This paper describes the development of an Automation Control Lab in the Department of Engineering Technology at the University. The lab facility includes pneumatic actuators/sensors, electrical relays/switches, and Programmable Logic Controllers (PLC). The major goal of the development is to help students gain hands-on industrial experience by conducting simple projects during the lecture hours and more advanced projects during the lab hours. Simulation software is also applied to reduce implementation time when developing complicated pneumatic circuits and PLC programs. In addition, three examples of industrial automation projects using PLC from the Technology Application Center (TAC) are also introduced to students to enhance their knowledge of automation controls. Performance assessment is conducted for this development
Chebyshev polynomial filtered subspace iteration in the Discontinuous Galerkin method for large-scale electronic structure calculations
The Discontinuous Galerkin (DG) electronic structure method employs an
adaptive local basis (ALB) set to solve the Kohn-Sham equations of density
functional theory (DFT) in a discontinuous Galerkin framework. The adaptive
local basis is generated on-the-fly to capture the local material physics, and
can systematically attain chemical accuracy with only a few tens of degrees of
freedom per atom. A central issue for large-scale calculations, however, is the
computation of the electron density (and subsequently, ground state properties)
from the discretized Hamiltonian in an efficient and scalable manner. We show
in this work how Chebyshev polynomial filtered subspace iteration (CheFSI) can
be used to address this issue and push the envelope in large-scale materials
simulations in a discontinuous Galerkin framework. We describe how the subspace
filtering steps can be performed in an efficient and scalable manner using a
two-dimensional parallelization scheme, thanks to the orthogonality of the DG
basis set and block-sparse structure of the DG Hamiltonian matrix. The
on-the-fly nature of the ALBs requires additional care in carrying out the
subspace iterations. We demonstrate the parallel scalability of the DG-CheFSI
approach in calculations of large-scale two-dimensional graphene sheets and
bulk three-dimensional lithium-ion electrolyte systems. Employing 55,296
computational cores, the time per self-consistent field iteration for a sample
of the bulk 3D electrolyte containing 8,586 atoms is 90 seconds, and the time
for a graphene sheet containing 11,520 atoms is 75 seconds.Comment: Submitted to The Journal of Chemical Physic
Achromatic contrast effects in infants: Adults and 4-month-old infants show similar deviations from Wallach’s ratio rule
AbstractWhen adults view a disk of light embedded in a higher luminance surround, the perceived lightness of the disk is largely determined by the surround to disk luminance ratio (Wallach’s ratio rule). In the present study, both adult and infant subjects were tested with multiple discrete trial procedures in which the surround luminance was decreased between the study and test phases of each trial. Tested with sequential lightness matching, adult subjects showed an approximate ratio rule, with a small but consistent deviation in the direction of a luminance match. Tested with a forced-choice novelty preference technique in combination with a cross-familiarization paradigm, 4-month-old infants showed preference minima that fell closer to the mean adult match than to the ratio rule. This finding suggests that, at least for a relatively simple visual display, 4-month-old infants’ looking preferences are governed by an adult-like achromatic contrast system
Intellectual Property Protection – Stimulating or Constraining Innovation and Technology Transfer?
Grassland farming is becoming more technically advanced leading to improvements in productivity, environmental outcomes and animal welfare. As a result, farmers have an increasing range of new innovations being made available to them. The question examined here is whether widespread uptake of new innovations by farmers is more effective when driven by marketing through dedicated paths to market where the intellectual property (IP) is controlled or through multiple paths to market where there is no IP control?
The role of IP in stimulating the development, manufacture and sale of new technologies is hotly debated. For plant breeders and patent owners, strong IP protection offers an effective form of security; and more importantly brings returns on investment through licences and commercialisation arrangements. When launching new products IP protection not only provides legal security but is confirmation that the product is unique, distinctive and of value. Some view IP rights as a way to foster innovation and invention by encouraging individuals to develop/invent new ideas from which they can potentially gain a return. Without the ability to capitalise on their work innovators have little incentive, other than an altruistic motive, to produce any invention.
However, there is an opposing view that patents and plant variety rights are “killing freedom to operate and crushing science with rules”, and in so doing are stifling innovation rather than encouraging it. Some believe that IP rights holders abuse the system to unfairly extend their monopoly on a technology and prevent others from using it to the benefit of the industry and the economy as a whole. We propose to examine the value and motivations for IP protection, and examine the different forms of IP protection available. Case studies will be used to show how IP protection may be a benefit or disadvantage to grassland farmers
Qualitative aspects of the entanglement in the three-level model with photonic crystals
This communication is an enquiry into the circumstances under which
concurrence and phase entropy methods can give an answer to the question of
quantum entanglement in the composite state when the photonic band gap is
exhibited by the presence of photonic crystals in a three-level system. An
analytic approach is proposed for any three-level system in the presence of
photonic band gap. Using this analytic solution, we conclusively calculate the
concurrence and phase entropy, focusing particularly on the entanglement
phenomena. Specifically, we use concurrence as a measure of entanglement for
dipole emitters situated in the thin slab region between two semi-infinite
one-dimensionally periodic photonic crystals, a situation reminiscent of planar
cavity laser structures. One feature of the regime considered here is that
closed-form evaluation of the time evolution may be carried out in the presence
of the detuning and the photonic band gap, which provides insight into the
difference in the nature of the concurrence function for atom-field coupling,
mode frequency and different cavity parameters. We demonstrate how fluctuations
in the phase and number entropies effected by the presence of the
photonic-band-gap. The outcomes are illustrated with numerical simulations
applied to GaAs. Finally, we relate the obtained results to instances of any
three-level system for which the entanglement cost can be calculated. Potential
experimental observations in solid-state systems are discussed and found to be
promising.Comment: 28 pages, 10 figures: Accepted in Applied Physics B: Laser and Optic
Exact Scaling Functions for Self-Avoiding Loops and Branched Polymers
It is shown that a recently conjectured form for the critical scaling
function for planar self-avoiding polygons weighted by their perimeter and area
also follows from an exact renormalization group flow into the branched polymer
problem, combined with the dimensional reduction arguments of Parisi and
Sourlas. The result is generalized to higher-order multicritical points,
yielding exact values for all their critical exponents and exact forms for the
associated scaling functions.Comment: 5 pages; v2: factors of 2 corrected; v.3: relation with existing
theta-point results clarified, some references added/update
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