15 research outputs found
ERROR CORRECTION CODE-BASED EMBEDDING IN ADAPTIVE RATE WIRELESS COMMUNICATION SYSTEMS
In this dissertation, we investigated the methods for development of embedded channels within error
correction mechanisms utilized to support adaptive rate communication systems. We developed an error
correction code-based embedding scheme suitable for application in modern wireless data communication
standards. We specifically implemented the scheme for both low-density parity check block codes and
binary convolutional codes. While error correction code-based information hiding has been previously
presented in literature, we sought to take advantage of the fact that these wireless systems have the ability to
change their modulation and coding rates in response to changing channel conditions. We utilized this
functionality to incorporate knowledge of the channel state into the scheme, which led to an increase in
embedding capacity. We conducted extensive simulations to establish the performance of our embedding
methodologies. Results from these simulations enabled the development of models to characterize the
behavior of the embedded channels and identify sources of distortion in the underlying communication
system. Finally, we developed expressions to define limitations on the capacity of these channels subject to
a variety of constraints, including the selected modulation type and coding rate of the communication
system, the current channel state, and the specific embedding implementation.Commander, United States NavyApproved for public release; distribution is unlimited
Smart and Portable Air-Quality Monitoring IoT Low-Cost Devices in Ibarra City, Ecuador
Nowadays, increasing air-pollution levels are a public health concern that affects all living
beings, with the most polluting gases being present in urban environments. For this reason, this
research presents portable Internet of Things (IoT) environmental monitoring devices that can be
installed in vehicles and that send message queuing telemetry transport (MQTT) messages to a server,
with a time series database allocated in edge computing. The visualization stage is performed in
cloud computing to determine the city air-pollution concentration using three different labels: low,
normal, and high. To determine the environmental conditions in Ibarra, Ecuador, a data analysis
scheme is used with outlier detection and supervised classification stages. In terms of relevant results,
the performance percentage of the IoT nodes used to infer air quality was greater than 90%. In
addition, the memory consumption was 14 Kbytes in a flash and 3 Kbytes in a RAM, reducing the
power consumption and bandwidth needed in traditional air-pollution measuring stations.Novo Nordisk Foundation NNF20OC0064411Corporacion Ecuatoriana para el Desarrollo de la Investigacion y la Academia (CEDIA), Ecuador CEPRA XII-2018-13Universidad de Las Americas (UDLA), Quito, Ecuador IEA.WHP.21.0
A Review of Remote Sensing Image Dehazing.
Remote sensing (RS) is one of the data collection technologies that help explore more earth surface information. However, RS data captured by satellite are susceptible to particles suspended during the imaging process, especially for data with visible light band. To make up for such deficiency, numerous dehazing work and efforts have been made recently, whose strategy is to directly restore single hazy data without the need for using any extra information. In this paper, we first classify the current available algorithm into three categories, i.e., image enhancement, physical dehazing, and data-driven. The advantages and disadvantages of each type of algorithm are then summarized in detail. Finally, the evaluation indicators used to rank the recovery performance and the application scenario of the RS data haze removal technique are discussed, respectively. In addition, some common deficiencies of current available methods and future research focus are elaborated
MULDASA:Multifactor Lexical Sentiment Analysis of Social-Media Content in Nonstandard Arabic Social Media
The semantically complicated Arabic natural vocabulary, and the shortage of available techniques and skills to capture Arabic emotions from text hinder Arabic sentiment analysis (ASA). Evaluating Arabic idioms that do not follow a conventional linguistic framework, such as contemporary standard Arabic (MSA), complicates an incredibly difficult procedure. Here, we define a novel lexical sentiment analysis approach for studying Arabic language tweets (TTs) from specialized digital media platforms. Many elements comprising emoji, intensifiers, negations, and other nonstandard expressions such as supplications, proverbs, and interjections are incorporated into the MULDASA algorithm to enhance the precision of opinion classifications. Root words in multidialectal sentiment LX are associated with emotions found in the content under study via a simple stemming procedure. Furthermore, a featureāsentiment correlation procedure is incorporated into the proposed technique to exclude viewpoints expressed that seem to be irrelevant to the area of concern. As part of our research into Saudi Arabian employability, we compiled a large sample of TTs in 6 different Arabic dialects. This research shows that this sentiment categorization method is useful, and that using all of the characteristics listed earlier improves the ability to accurately classify peopleās feelings. The classification accuracy of the proposed algorithm improved from 83.84% to 89.80%. Our approach also outperformed two existing research projects that employed a lexical approach for the sentiment analysis of Saudi dialect