14,113 research outputs found

    Graduate Catalog of Studies, 2023-2024

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    Analysis and Design of Non-Orthogonal Multiple Access (NOMA) Techniques for Next Generation Wireless Communication Systems

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    The current surge in wireless connectivity, anticipated to amplify significantly in future wireless technologies, brings a new wave of users. Given the impracticality of an endlessly expanding bandwidth, there’s a pressing need for communication techniques that efficiently serve this burgeoning user base with limited resources. Multiple Access (MA) techniques, notably Orthogonal Multiple Access (OMA), have long addressed bandwidth constraints. However, with escalating user numbers, OMA’s orthogonality becomes limiting for emerging wireless technologies. Non-Orthogonal Multiple Access (NOMA), employing superposition coding, serves more users within the same bandwidth as OMA by allocating different power levels to users whose signals can then be detected using the gap between them, thus offering superior spectral efficiency and massive connectivity. This thesis examines the integration of NOMA techniques with cooperative relaying, EXtrinsic Information Transfer (EXIT) chart analysis, and deep learning for enhancing 6G and beyond communication systems. The adopted methodology aims to optimize the systems’ performance, spanning from bit-error rate (BER) versus signal to noise ratio (SNR) to overall system efficiency and data rates. The primary focus of this thesis is the investigation of the integration of NOMA with cooperative relaying, EXIT chart analysis, and deep learning techniques. In the cooperative relaying context, NOMA notably improved diversity gains, thereby proving the superiority of combining NOMA with cooperative relaying over just NOMA. With EXIT chart analysis, NOMA achieved low BER at mid-range SNR as well as achieved optimal user fairness in the power allocation stage. Additionally, employing a trained neural network enhanced signal detection for NOMA in the deep learning scenario, thereby producing a simpler signal detection for NOMA which addresses NOMAs’ complex receiver problem

    Intelligent Technologies Supporting the Management of a Smart City. Qualitative Approach

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    Intelligent technologies such as Business Intelligence systems, big data, artificial intelligence including machine learning and cognitive technologies play crucial role in the process of a smart city management. The aim of the paper is to indicate the role of intelligent solutions in the management of a contemporary city, particularly focusing on the support of decision making process. The research methodology is based on a qualitative approach where six case studies were conducted in the selected big cities in Poland in 2021 year. The respondents belonged to the group of mainly managers of IT departments in the cities. The case study analyses showed that implemented intelligent solutions in the process of a smart city management positively and significantly affect efficacy, efficiency, quality, and acceleration of the decision-making process and also support the creation of a particular city development strategy. The paper puts also an emphasis on the review of AI applications within the concept of smart city in a big worldwide metropolies

    Die unsicheren Kanäle

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    Zeitgenössische IT-Sicherheit operiert in einer Überbietungslogik zwischen Sicherheitsvorkehrungen und Angriffsszenarien. Diese paranoid strukturierte Form negativer Sicherheit lässt sich vom Ursprung der IT-Sicherheit in der modernen Kryptografie über Computerviren und -würmer, Ransomware und Backdoors bis hin zum AIDS-Diskurs der 1980er Jahre nachzeichnen. Doch Sicherheit in und mit digital vernetzten Medien lässt sich auch anders denken: Marie-Luise Shnayien schlägt die Verwendung eines reparativen, queeren Sicherheitsbegriffs vor, dessen Praktiken zwar nicht auf der Ebene des Technischen angesiedelt sind, aber dennoch nicht ohne ein genaues Wissen desselben auskommen

    LIPIcs, Volume 251, ITCS 2023, Complete Volume

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    LIPIcs, Volume 251, ITCS 2023, Complete Volum

    Effects of municipal smoke-free ordinances on secondhand smoke exposure in the Republic of Korea

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    ObjectiveTo reduce premature deaths due to secondhand smoke (SHS) exposure among non-smokers, the Republic of Korea (ROK) adopted changes to the National Health Promotion Act, which allowed local governments to enact municipal ordinances to strengthen their authority to designate smoke-free areas and levy penalty fines. In this study, we examined national trends in SHS exposure after the introduction of these municipal ordinances at the city level in 2010.MethodsWe used interrupted time series analysis to assess whether the trends of SHS exposure in the workplace and at home, and the primary cigarette smoking rate changed following the policy adjustment in the national legislation in ROK. Population-standardized data for selected variables were retrieved from a nationally representative survey dataset and used to study the policy action’s effectiveness.ResultsFollowing the change in the legislation, SHS exposure in the workplace reversed course from an increasing (18% per year) trend prior to the introduction of these smoke-free ordinances to a decreasing (−10% per year) trend after adoption and enforcement of these laws (β2 = 0.18, p-value = 0.07; β3 = −0.10, p-value = 0.02). SHS exposure at home (β2 = 0.10, p-value = 0.09; β3 = −0.03, p-value = 0.14) and the primary cigarette smoking rate (β2 = 0.03, p-value = 0.10; β3 = 0.008, p-value = 0.15) showed no significant changes in the sampled period. Although analyses stratified by sex showed that the allowance of municipal ordinances resulted in reduced SHS exposure in the workplace for both males and females, they did not affect the primary cigarette smoking rate as much, especially among females.ConclusionStrengthening the role of local governments by giving them the authority to enact and enforce penalties on SHS exposure violation helped ROK to reduce SHS exposure in the workplace. However, smoking behaviors and related activities seemed to shift to less restrictive areas such as on the streets and in apartment hallways, negating some of the effects due to these ordinances. Future studies should investigate how smoke-free policies beyond public places can further reduce the SHS exposure in ROK

    The use of proxies in designing for and with autistic children: supporting friendship as a case study

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    Participatory Design (PD) is an approach for designing new technologies which involves end users in the design process. It is generally accepted that involving users in the design process gives them a sense of ownership over the final product which enhances its usability and acceptance by the target population. Employing a PD approach can introduce multiple challenges especially when working with autistic children. Many approaches for involving autistic children and children with special needs were developed to address these challenges. However, these frameworks introduce their own limitations as well. There is an ethical dilemma to consider in the involvement of autistic children in the design process. Although we established the ethical benefit of involving children, we did not address the ethical issues that will result from involving them in these research projects. Among other issues, the nature of design workshops we as a community currently run require working with unfamiliar researchers and communicating with them while social and communication differences are one of the main diagnostic criteria for autism. When designing for autistic children and other vulnerable populations an alternative (or most often an additional) approach is designing with proxies. Proxies for the child can be one of several groups of other stakeholders, such as: teachers, parents and siblings. Each of these groups may inform the design process, from their particular perspective, and as proxies for the target group of autistic children. Decisions need to be made about what stages in the design process are suited to their participation, and the role they play in each case. For this reason, we explore the role of teachers, parents, autistic adults and neurotypical children as proxies in the design process. To explore the roles of proxies we chose friendship between autistic and neurotypical children as the context we are designing for. We are interested in understanding the nature of children's friendships and the potential for technology to support them. Although children themselves are the ones who experience friendship and challenges around its development and peer interaction, they might find it difficult to articulate the challenges they face. Furthermore, it is unrealistic to expect children to identify strategies to help them overcome the challenges with friendship development that they are facing as it assumes children have the social skills to come up with these strategies in the first place. Hence, it is necessary in this context to consider proxies who can identify challenges and suggest ways to overcome them

    Distributed Deep Neural-Network-Based Middleware for Cyber-Attacks Detection in Smart IoT Ecosystem: A Novel Framework and Performance Evaluation Approach

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    Cyberattacks always remain the major threats and challenging issues in the modern digital world. With the increase in the number of internet of things (IoT) devices, security challenges in these devices, such as lack of encryption, malware, ransomware, and IoT botnets, leave the devices vulnerable to attackers that can access and manipulate the important data, threaten the system, and demand ransom. The lessons from the earlier experiences of cyberattacks demand the development of the best-practices benchmark of cybersecurity, especially in modern Smart Environments. In this study, we propose an approach with a framework to discover malware attacks by using artificial intelligence (AI) methods to cover diverse and distributed scenarios. The new method facilitates proactively tracking network traffic data to detect malware and attacks in the IoT ecosystem. Moreover, the novel approach makes Smart Environments more secure and aware of possible future threats. The performance and concurrency testing of the deep neural network (DNN) model deployed in IoT devices are computed to validate the possibility of in-production implementation. By deploying the DNN model on two selected IoT gateways, we observed very promising results, with less than 30 kb/s increase in network bandwidth on average, and just a 2% increase in CPU consumption. Similarly, we noticed minimal physical memory and power consumption, with 0.42 GB and 0.2 GB memory usage for NVIDIA Jetson and Raspberry Pi devices, respectively, and an average 13.5% increase in power consumption per device with the deployed model. The ML models were able to demonstrate nearly 93% of detection accuracy and 92% f1-score on both utilized datasets. The result of the models shows that our framework detects malware and attacks in Smart Environments accurately and efficiently.publishedVersio

    The Importance of Conceptualising the Human-Centric Approach in Maintaining and Promoting Cybersecurity-Hygiene in Healthcare 4.0

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    The cyberspace depicts an increasing number of difficulties related to security, especially in healthcare. This is evident from how vulnerable critical infrastructures are to cyberattacks and are unprotected against cybercrime. Users, ideally, should maintain a good level of cyber hygiene, via regular software updates and the development of unique passwords, as an effective way to become resilient to cyberattacks. Cyber security breaches are a top priority, and most users are aware that their behaviours may put them at risk; however, they are not educated to follow best practices, such as protecting their passwords. Mass cyber education may serve as a means to offset poor cyber security behaviours; however, mandatory education becomes a questionable point if the content is not focused on human factors, using human-centric approaches and taking into account end users’ behaviours, which is currently the case. The nature of the present paper is largely exploratory, and the purpose is two-fold: To present and explore the cyber hygiene definition, context and habits of end users in order to strengthen our understanding of users. Our paper reports the best practices that should be used by healthcare organisations and healthcare professionals to maintain good cyber hygiene and how these can be applied via a healthcare use case scenario to increase awareness related to data privacy and cybersecurity. This is an issue of great importance and urgency considering the rapid increase of cyberattacks in healthcare organisations, mainly due to human errors. Further to that, based on human-centric approaches, our long-term vision and future work involves facilitating the development of efficient practices and education associated with cybersecurity hygiene via a flexible, adaptable and practical framework

    Digital support for alcohol moderation and smoking cessation in cancer survivors

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