16 research outputs found
The image of Turkey in Egyptian media: Content and discourse analysis of the coverage in three Egyptian newspapers
This study investigates the image of Turkey in Egyptian newspapers by conducting a content and discourse analysis of three Egyptian newspapers, Al-Ahram, El-Shorouk, and Almasry Alyoum, from January 2012 to December 2014. Based on previous literature, this study applied two theoretical frameworks: 1) Benedict Anderson\u27s hypnosis of imagined communities and 2) media framing theory. To apply media framing, the Semetko and Valkenburg (2000) framing scale was employed. Following that, a rhetorical discourse was used to investigate Anderson\u27s thesis. The study\u27s finding matched Semetko and Valkenburg\u27s framing scale. Both indicated that the attribution of responsibility is the most frequent frame in news. Finally, the discourse analysis resulted that newspapers could be deployed as an instrument to disseminate shared thoughts and ideologies among diverse citizens
Scattered EXIT Charts for Finite Length LDPC Code Design
We introduce the Scattered Extrinsic Information Transfer (S-EXIT) chart as a
tool for optimizing degree profiles of short length Low-Density Parity-Check
(LDPC) codes under iterative decoding. As degree profile optimization is
typically done in the asymptotic length regime, there is space for further
improvement when considering the finite length behavior. We propose to consider
the average extrinsic information as a random variable, exploiting its specific
distribution properties for guiding code design. We explain, step-by-step, how
to generate an S-EXIT chart for short-length LDPC codes. We show that this
approach achieves gains in terms of bit error rate (BER) of 0.5 dB and 0.6 dB
over the additive white Gaussian noise (AWGN) channel for codeword lengths of
128 and 180 bits, respectively, at a target BER of when compared to
conventional Extrinsic Information Transfer (EXIT) chart-based optimization.
Also, a performance gain for the Binary Erasure Channel (BEC) for a block
(i.e., codeword) length of 180 bits is shown.Comment: in IEEE International Conference on Communications (ICC), May 201
Belief Propagation Decoding of Polar Codes on Permuted Factor Graphs
We show that the performance of iterative belief propagation (BP) decoding of
polar codes can be enhanced by decoding over different carefully chosen factor
graph realizations. With a genie-aided stopping condition, it can achieve the
successive cancellation list (SCL) decoding performance which has already been
shown to achieve the maximum likelihood (ML) bound provided that the list size
is sufficiently large. The proposed decoder is based on different realizations
of the polar code factor graph with randomly permuted stages during decoding.
Additionally, a different way of visualizing the polar code factor graph is
presented, facilitating the analysis of the underlying factor graph and the
comparison of different graph permutations. In our proposed decoder, a high
rate Cyclic Redundancy Check (CRC) code is concatenated with a polar code and
used as an iteration stopping criterion (i.e., genie) to even outperform the
SCL decoder of the plain polar code (without the CRC-aid). Although our
permuted factor graph-based decoder does not outperform the SCL-CRC decoder, it
achieves, to the best of our knowledge, the best performance of all iterative
polar decoders presented thus far.Comment: in IEEE Wireless Commun. and Networking Conf. (WCNC), April 201
Decoder-in-the-Loop: Genetic Optimization-based LDPC Code Design
LDPC code design tools typically rely on asymptotic code behavior and are
affected by an unavoidable performance degradation due to model imperfections
in the short length regime. We propose an LDPC code design scheme based on an
evolutionary algorithm, the Genetic Algorithm (GenAlg), implementing a
"decoder-in-the-loop" concept. It inherently takes into consideration the
channel, code length and the number of iterations while optimizing the
error-rate of the actual decoder hardware architecture. We construct short
length LDPC codes (i.e., the parity-check matrix) with error-rate performance
comparable to, or even outperforming that of well-designed standardized short
length LDPC codes over both AWGN and Rayleigh fading channels. Our proposed
algorithm can be used to design LDPC codes with special graph structures (e.g.,
accumulator-based codes) to facilitate the encoding step, or to satisfy any
other practical requirement. Moreover, GenAlg can be used to design LDPC codes
with the aim of reducing decoding latency and complexity, leading to coding
gains of up to dB and dB at BLER of for both AWGN and
Rayleigh fading channels, respectively, when compared to state-of-the-art short
LDPC codes. Also, we analyze what can be learned from the resulting codes and,
as such, the GenAlg particularly highlights design paradigms of short length
LDPC codes (e.g., codes with degree-1 variable nodes obtain very good results).Comment: in IEEE Access, 201