178 research outputs found
Spread Complexity in free fermion models
We study spread complexity and the statistics of work done for quenches in
the three-spin interacting Ising model, the XY spin chain, and the
Su-Schrieffer-Heeger model. We study these models without quench and for
different schemes of quenches, such as sudden quench and multiple sudden
quenches. We employ the Floquet operator technique to investigate all three
models in the presence of time-dependent periodic driving of parameters. In
contrast to the sudden quenched cases, the periodically varying parameter case
clearly shows non-analytical behaviour near the critical point. We also
elucidate the relation between work done and the Lanczos coefficient and how
the statistics of work done behave near critical points.Comment: 23 pages, 18 figure
Passenger Screening using Deep Learning and Artificial Neural Networks
In this research, we have to detect the contrabands hidden in the human body’s scanned images at airport security machines using segmentation and classification. Present algorithm of security scanning machines at the airports of USA are producing high rate of false negatives which in cases lead to engage in a secondary, manual screening process that slows everything down. So to resolve this problem and to improve the detection of contrabands, new and efficient algorithm need to be made
Complexity and quenches in models with three and four spin interactions
We study information theoretic quantities in models with three and four spin
interactions. These models show distinctive characteristics compared to their
nearest neighbour counterparts. Here, we quantify these in terms of the Nielsen
complexity in static and quench scenarios, the Fubini-Study complexity, and the
entanglement entropy. The models that we study have a rich phase structure, and
we show how the difference in the nature of phase transitions in these,
compared to ones with nearest neighbour interactions, result in different
behaviour of information theoretic quantities, from ones known in the
literature. For example, the derivative of the Nielsen complexity does not
diverge but shows a discontinuity near continuous phase transitions, and the
Fubini-Study complexity may be regular and continuous across such transitions.
The entanglement entropy shows a novel discontinuity both at first and second
order quantum phase transitions. We also study multiple quench scenarios in
these models and contrast these with quenches in the transverse XY model.Comment: 12 Pages, 11 Figure
FOTOC complexity in an extended Lipkin-Meshkov-Glick model
We study fidelity out-of-time-order correlators (FOTOCs) in an extended
Lipkin-Meshkov-Glick model and demonstrate that these exhibit distinctive
behaviour at quantum phase transitions in both the ground and the excited
states. We show that the dynamics of the FOTOC have different behaviour in the
symmetric and broken-symmetry phases, and as one approaches phase transition.
If we rescale the FOTOC operator with time, then for small times, we establish
that it is identical to the Loschmidt echo. We also compute the Nielsen
complexity of the FOTOC operator in both phases, and apply this operator on the
ground and excited states to obtain the quasi-scrambled state of the model. The
FOTOC operator introduces a small perturbation on the original ground and
excited states. For this perturbed state, we compute the quantum information
metric to first order in perturbation, in the thermodynamic limit. We find that
the associated Ricci scalar diverges at the phase transition on the
broken-symmetry phase side, in contrast to the zeroth order result. Finally, we
comment upon the Fubini-Study complexity in this model.Comment: Minor corrections. 10 Pages, 5 Figure
Machine Learning Decoder for 5G NR PUCCH Format 0
5G cellular systems depend on the timely exchange of feedback control
information between the user equipment and the base station. Proper decoding of
this control information is necessary to set up and sustain high throughput
radio links. This paper makes the first attempt at using Machine Learning
techniques to improve the decoding performance of the Physical Uplink Control
Channel Format 0. We use fully connected neural networks to classify the
received samples based on the uplink control information content embedded
within them. The trained neural network, tested on real-time wireless captures,
shows significant improvement in accuracy over conventional DFT-based decoders,
even at low SNR. The obtained accuracy results also demonstrate conformance
with 3GPP requirements.Comment: Submitted to NCC conferenc
A STUDY ON USE OF RICE HUSK ASH IN CONCRETE
The rice husk is an agricultural waste which is obtained from milling process of paddy and approximately 22% of the
weight of paddy is rice husk. The waste is used as fuel in producing stream in parboiling process. The 25 % the weight
of husk is converted into ash which is known as rice husk ash (RHA) and is again a waste which is disposed. This ash
consists of amorphous silica which can be used as pozzolana in making concrete and cement instead of disposing it
without compromising on the properties of cement or concrete if replaced in specific proportion with other
constituents of cement or concrete. In this study the ordinary Portland cement is replaced in different proportion with
RHA to obtain concrete with comparable and satisfactory strength and properties to that of normal concrete. The
proportions of replacement chosen are at 2.5% interval starting from 5 % to 15 % and the casted concrete were tested
under compression at different ages and results obtained are compared with normal concrete of same grade and it is
concluded that the results are comparable
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