22,329 research outputs found
Depth of anesthesia control using internal model control techniques
The major difficulty in the design of closed-loop control during anaesthesia is the inherent patient variability due to differences in demographic and drug tolerance. These
discrepancies are translated into the pharmacokinetics (PK),
and pharmacodynamics (PD). These uncertainties may affect
the stability of the closed loop control system. This paper aims at developing predictive controllers using Internal Model Control technique. This study develops patient dose-response models and to provide an adequate drug administration regimen for the anaesthesia to avoid under or over dosing of the patients. The controllers are designed to compensate for patients inherent drug response variability, to achieve the best output disturbance rejection, and to maintain optimal set point response. The results are evaluated compared with traditional PID controller and the performance is confirmed in our
simulation
Projective construction of two-dimensional symmetry-protected topological phases with U(1), SO(3), or SU(2) symmetries
We propose a general approach to construct symmetry protected topological
(SPT) states i.e the short-range entangled states with symmetry) in 2D
spin/boson systems on lattice. In our approach, we fractionalize spins/bosons
into different fermions, which occupy nontrivial Chern bands. After the
Gutzwiller projection of the free fermion state obtained by filling the Chern
bands, we can obtain SPT states on lattice. In particular, we constructed a
U(1) SPT state of a spin-1 model, a SO(3) SPT state of a boson system with
spin-1 bosons and spinless bosons, and a SU(2) SPT state of a spin-1/2 boson
system. By applying the "spin gauge field" which directly couples to the spin
density and spin current of components, we also calculate the quantum
spin Hall conductance in each SPT state. The projective ground states can be
further studied numerically in the future by variational Monte Carlo etc.Comment: 7+ pages, accepted by Phys. Rev.
Electronic height indicator for agricultural machines
This paper addresses the design and development of a low cost electronic height indicator for a self-propelled spray rig. The prime objective is to give a spray rig operator an accurate indication of the boom height above the ground by using an electronic display in the tractor cabin to improve the efficiency of chemical application. This indicator is implemented using a microcontroller and a Hall-effect sensor. The field test proves that this indicator has improved the spraying performance by eliminating human error in estimating boom height, especially during night-time and dusty conditions
Design and Synthesis of Quasi Dual-mode, Elliptic Coaxial Filter
This article introduces the design of a novel quasi dual-mode, elliptic coaxial filter. The transfer function is mapped to a generalized Chebyshev prototype with symmetrically located transmission zeros (TZs) where the coupling values are extracted. Furthermore, the miniaturization is achieved by incorporating stepped-impedance coaxial line with inductive element shunted at the center to exhibit a quasi dual-mode property. Theoretical analysis together with experimental prototype is presented. The center frequency of the filter is 2.7 GHz. The simulated and measured insertion loss/return loss are 1.2 dB/ 15 dB and 2.5 dB/11.5 dB respectively. Both theoretical and measured results show a very good agreement
Translation invariant topological superconductors on lattice
In this paper we introduce four Z_2 topological indices zeta_k=0,1 at
k=(0,0), (0,pi), (pi, 0), (pi, pi) characterizing 16 universal classes of 2D
superconducting states that have translation symmetry but may break any other
symmetries. The 16 classes of superconducting states are distinguished by their
even/odd numbers of fermions on even-by-even, even-by-odd, odd-by-even, and
odd-by-odd lattices. As a result, the 16 classes topological superconducting
states exist even for interacting systems. For non-interacting systems, we find
that zeta_k is the number of electrons on k=(0,0), (0,pi), (pi, 0), or (pi,pi)
orbitals (mod 2) in the ground state. For 3D superconducting states with only
translation symmetry, there are 256 different types of topological
superconductors.Comment: 4 pages, RevTeX
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