20,262 research outputs found
Optimal Transmit Power and Channel-Information Bit Allocation With Zeroforcing Beamforming in MIMO-NOMA and MIMO-OMA Downlinks
In downlink, a base station (BS) with multiple transmit antennas applies
zeroforcing beamforming to transmit to single-antenna mobile users in a cell.
We propose the schemes that optimize transmit power and the number of bits for
channel direction information (CDI) for all users to achieve the max-min
signal-to-interference plus noise ratio (SINR) fairness. The optimal allocation
can be obtained by a geometric program for both non-orthogonal multiple access
(NOMA) and orthogonal multiple access (OMA). For NOMA, 2 users with highly
correlated channels are paired and share the same transmit beamforming. In some
small total-CDI rate regimes, we show that NOMA can outperform OMA by as much
as 3 dB. The performance gain over OMA increases when the
correlation-coefficient threshold for user pairing is set higher. To reduce
computational complexity, we propose to allocate transmit power and CDI rate to
groups of multiple users instead of individual users. The user grouping scheme
is based on K-means over the user SINR. We also propose a progressive filling
scheme that performs close to the optimum, but can reduce the computation time
by almost 3 orders of magnitude in some numerical examples
The Metaverse: Survey, Trends, Novel Pipeline Ecosystem & Future Directions
The Metaverse offers a second world beyond reality, where boundaries are
non-existent, and possibilities are endless through engagement and immersive
experiences using the virtual reality (VR) technology. Many disciplines can
benefit from the advancement of the Metaverse when accurately developed,
including the fields of technology, gaming, education, art, and culture.
Nevertheless, developing the Metaverse environment to its full potential is an
ambiguous task that needs proper guidance and directions. Existing surveys on
the Metaverse focus only on a specific aspect and discipline of the Metaverse
and lack a holistic view of the entire process. To this end, a more holistic,
multi-disciplinary, in-depth, and academic and industry-oriented review is
required to provide a thorough study of the Metaverse development pipeline. To
address these issues, we present in this survey a novel multi-layered pipeline
ecosystem composed of (1) the Metaverse computing, networking, communications
and hardware infrastructure, (2) environment digitization, and (3) user
interactions. For every layer, we discuss the components that detail the steps
of its development. Also, for each of these components, we examine the impact
of a set of enabling technologies and empowering domains (e.g., Artificial
Intelligence, Security & Privacy, Blockchain, Business, Ethics, and Social) on
its advancement. In addition, we explain the importance of these technologies
to support decentralization, interoperability, user experiences, interactions,
and monetization. Our presented study highlights the existing challenges for
each component, followed by research directions and potential solutions. To the
best of our knowledge, this survey is the most comprehensive and allows users,
scholars, and entrepreneurs to get an in-depth understanding of the Metaverse
ecosystem to find their opportunities and potentials for contribution
The Viability and Potential Consequences of IoT-Based Ransomware
With the increased threat of ransomware and the substantial growth of the Internet of Things (IoT) market, there is significant motivation for attackers to carry out IoT-based ransomware campaigns. In this thesis, the viability of such malware is tested.
As part of this work, various techniques that could be used by ransomware developers to attack commercial IoT devices were explored. First, methods that attackers could use to communicate with the victim were examined, such that a ransom note was able to be reliably sent to a victim. Next, the viability of using "bricking" as a method of ransom was evaluated, such that devices could be remotely disabled unless the victim makes a payment to the attacker. Research was then performed to ascertain whether it was possible to remotely gain persistence on IoT devices, which would improve the efficacy of existing ransomware methods, and provide opportunities for more advanced ransomware to be created. Finally, after successfully identifying a number of persistence techniques, the viability of privacy-invasion based ransomware was analysed.
For each assessed technique, proofs of concept were developed. A range of devices -- with various intended purposes, such as routers, cameras and phones -- were used to test the viability of these proofs of concept. To test communication hijacking, devices' "channels of communication" -- such as web services and embedded screens -- were identified, then hijacked to display custom ransom notes. During the analysis of bricking-based ransomware, a working proof of concept was created, which was then able to remotely brick five IoT devices. After analysing the storage design of an assortment of IoT devices, six different persistence techniques were identified, which were then successfully tested on four devices, such that malicious filesystem modifications would be retained after the device was rebooted. When researching privacy-invasion based ransomware, several methods were created to extract information from data sources that can be commonly found on IoT devices, such as nearby WiFi signals, images from cameras, or audio from microphones. These were successfully implemented in a test environment such that ransomable data could be extracted, processed, and stored for later use to blackmail the victim.
Overall, IoT-based ransomware has not only been shown to be viable but also highly damaging to both IoT devices and their users. While the use of IoT-ransomware is still very uncommon "in the wild", the techniques demonstrated within this work highlight an urgent need to improve the security of IoT devices to avoid the risk of IoT-based ransomware causing havoc in our society. Finally, during the development of these proofs of concept, a number of potential countermeasures were identified, which can be used to limit the effectiveness of the attacking techniques discovered in this PhD research
Теорія систем мобільних інфокомунікацій. Системна архітектура
Навчальний посібник містить опис логічних та фізичних структур, процедур,
алгоритмів, протоколів, принципів побудови і функціонування мереж
стільникового мобільного зв’язку (до 3G) і мобільних інфокомунікацій (4G і вище),
приділяючи увагу розгляду загальних архітектур мереж операторів мобільного
зв’язку, їх управління і координування, неперервності еволюції розвитку засобів
функціонування і способів надання послуг таких мереж. Посібник структурно має
сім розділів і побудований так, що складність матеріалу зростає з кожним
наступним розділом. Навчальний посібник призначено для здобувачів ступеня
бакалавра за спеціальністю 172 «Телекомунікації та радіотехніка», буде також
корисним для аспірантів, наукових та інженерно-технічних працівників за
напрямом інформаційно-телекомунікаційних систем та технологій.The manual contains a description of the logical and physical structures, procedures, algorithms, protocols, principles of construction and operation of cellular networks for mobile communications (up to 3G) and mobile infocommunications (4G and higher), paying attention to the consideration of general architectures of mobile operators' networks, their management, and coordination, the continuous evolution of the development of the means of operation and methods of providing services of such networks. The manual has seven structural sections and is structured in such a way that the complexity of the material increases with each subsequent chapter. The textbook is intended for applicants for a bachelor's degree in specialty 172 "Telecommunications and Radio Engineering", and will also be useful to graduate students, and scientific and engineering workers in the direction of information and telecommunication systems and technologies
A Design Science Research Approach to Smart and Collaborative Urban Supply Networks
Urban supply networks are facing increasing demands and challenges and thus constitute a relevant field for research and practical development. Supply chain management holds enormous potential and relevance for society and everyday life as the flow of goods and information are important economic functions. Being a heterogeneous field, the literature base of supply chain management research is difficult to manage and navigate. Disruptive digital technologies and the implementation of cross-network information analysis and sharing drive the need for new organisational and technological approaches. Practical issues are manifold and include mega trends such as digital transformation, urbanisation, and environmental awareness.
A promising approach to solving these problems is the realisation of smart and collaborative supply networks. The growth of artificial intelligence applications in recent years has led to a wide range of applications in a variety of domains. However, the potential of artificial intelligence utilisation in supply chain management has not yet been fully exploited. Similarly, value creation increasingly takes place in networked value creation cycles that have become continuously more collaborative, complex, and dynamic as interactions in business processes involving information technologies have become more intense.
Following a design science research approach this cumulative thesis comprises the development and discussion of four artefacts for the analysis and advancement of smart and collaborative urban supply networks. This thesis aims to highlight the potential of artificial intelligence-based supply networks, to advance data-driven inter-organisational collaboration, and to improve last mile supply network sustainability. Based on thorough machine learning and systematic literature reviews, reference and system dynamics modelling, simulation, and qualitative empirical research, the artefacts provide a valuable contribution to research and practice
Redefining quality interpersonal communication and communication activities in marriage from divorcees’ perspectives
Quality interpersonal communication is essential in the development and maintenance of any relationship, including marriage. As society adapts to new avenues of communication, married couples often underestimate the relevance of interpersonal communication in their relationship due to their lack of understanding of quality interpersonal communication. Therefore, this study investigated the conceptualisation of quality interpersonal communication through the lens of Relational Dialectic Theory and communication activities in marriage from the perspectives of divorcees. This study also explored the antecedents of poor-quality interpersonal communication and its repercussions on married couples. The present study also extended Knapp’s Relational Development Model by incorporating communication technology as a medium of communication. In-depth interviews were conducted on 20 divorcees from different states in Malaysia, chosen through a purposive sampling technique. The gathered data was then evaluated and combined in a thematic data analysis using the NVivo 12 software. This study discovers that the definitions of quality interpersonal communication are divided into seven (7) categories, with communication skills, intimacy, and characters identified as the top three significant traits. Results of this study also indicate that spouses use various medium of communication based on their circumstances but prefer face-to-face communication. However, communication occurrences between spouses are low and mostly negative, with the majority of them mainly involving households and children. The other antecedents of poor-quality interpersonal communication are communication skills, attitudes, third-party involvement, and emotional condition. The current study concludes that emotional condition is one of the protuberant effects of poor-quality interpersonal communication. All in all, the current study provides a new paradigm in Knapp’s Relational Development Model through the incorporation of the effects of poor-quality interpersonal communication into the deterioration stages of the model
Associated Random Neural Networks for Collective Classification of Nodes in Botnet Attacks
Botnet attacks are a major threat to networked systems because of their
ability to turn the network nodes that they compromise into additional
attackers, leading to the spread of high volume attacks over long periods. The
detection of such Botnets is complicated by the fact that multiple network IP
addresses will be simultaneously compromised, so that Collective Classification
of compromised nodes, in addition to the already available traditional methods
that focus on individual nodes, can be useful. Thus this work introduces a
collective Botnet attack classification technique that operates on traffic from
an n-node IP network with a novel Associated Random Neural Network (ARNN) that
identifies the nodes which are compromised. The ARNN is a recurrent
architecture that incorporates two mutually associated, interconnected and
architecturally identical n-neuron random neural networks, that act
simultneously as mutual critics to reach the decision regarding which of n
nodes have been compromised. A novel gradient learning descent algorithm is
presented for the ARNN, and is shown to operate effectively both with
conventional off-line training from prior data, and with on-line incremental
training without prior off-line learning. Real data from a 107 node packet
network is used with over 700,000 packets to evaluate the ARNN, showing that it
provides accurate predictions. Comparisons with other well-known state of the
art methods using the same learning and testing datasets, show that the ARNN
offers significantly better performance
Critical Review on Internet of Things (IoT): Evolution and Components Perspectives
Technological advancement in recent years has transformed the internet to a network where everything is linked, and everyday objects can be recognised and controlled. This interconnection is popularly termed as the Internet of Things (IoT). Although, IoT remains popular in academic literature, limited studies have focused on its evolution, components, and implications for industries. Hence, the focus of this book chapter is to explore these dimensions, and their implications for industries. The study adopted the critical review method, to address these gaps in the IoT literature for service and manufacturing industries. Furthermore, the relevance for IoT for service and manufacturing industries were also discussed. While the impact of IoT in the next five years is expected to be high by industry practitioners, experts consider the current degree of its implementation across industry to be on the average. This critical review contributes theoretically to the literature on IoT. In effect, the intense implementation of the IoT, IIoT and IoS will go a long way in ensuring improvements in various industries that would in the long run positively impact the general livelihood of people as well as the way of doing things. Practical implications and suggestions for future studies have been discussed
Big Tech and research funding: A bibliometric approach
Dissertation presented as the partial requirement for obtaining a Master's degree in Data Science and Advanced Analytics, specialization in Business AnalyticsTechnology companies have radically transformed our daily life in the recent years with help of the wide usage of internet. While transforming our lives, these companies also have grown up even bigger in the recent times and have become more powerful not only financially, but also in terms of computing power and data. Although there have been lots of research done on the influence of large digital economy players (Big Tech) in different fields, the academic influence of these companies is little understood. By drawing on 130,000 academic papers for which there is evidence of support by the Big Tech, the present work applies bibliometric approaches (on the metadata) and text mining techniques (on the contents) to shed a light on the outcomes of this relationship. In particular, we take into consideration research funding (direct strategies) and conference sponsorships (indirect strategies) to empirically explore this relatively unexplored side of Big Tech’s influence in contemporary society. While developing the analysis a key limitation was the scarcity of prior work exploring the connections between digital platforms and the scientific enterprise. There are several results that come to light from such a perspective, one of these findings is that among the research supported by Big Tech companies, there is big gap between the number of outcomes with the content about the technical perspectives (like machine learning or artificial intelligence) than the content about reflexive (say ethical or environmental) dimensions of innovation, ladder being very small. These findings may stimulate further inquiries into identifying the possible risks, if any, are generated from the direct and indirect financial support by corporate informational giants to academia. The causes and consequences of this non-market activity by companies with big market power may require further attention and research in this field
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