3,827 research outputs found
UMSL Bulletin 2023-2024
The 2023-2024 Bulletin and Course Catalog for the University of Missouri St. Louis.https://irl.umsl.edu/bulletin/1088/thumbnail.jp
Modern computing: Vision and challenges
Over the past six decades, the computing systems field has experienced significant transformations, profoundly impacting society with transformational developments, such as the Internet and the commodification of computing. Underpinned by technological advancements, computer systems, far from being static, have been continuously evolving and adapting to cover multifaceted societal niches. This has led to new paradigms such as cloud, fog, edge computing, and the Internet of Things (IoT), which offer fresh economic and creative opportunities. Nevertheless, this rapid change poses complex research challenges, especially in maximizing potential and enhancing functionality. As such, to maintain an economical level of performance that meets ever-tighter requirements, one must understand the drivers of new model emergence and expansion, and how contemporary challenges differ from past ones. To that end, this article investigates and assesses the factors influencing the evolution of computing systems, covering established systems and architectures as well as newer developments, such as serverless computing, quantum computing, and on-device AI on edge devices. Trends emerge when one traces technological trajectory, which includes the rapid obsolescence of frameworks due to business and technical constraints, a move towards specialized systems and models, and varying approaches to centralized and decentralized control. This comprehensive review of modern computing systems looks ahead to the future of research in the field, highlighting key challenges and emerging trends, and underscoring their importance in cost-effectively driving technological progress
UMSL Bulletin 2022-2023
The 2022-2023 Bulletin and Course Catalog for the University of Missouri St. Louis.https://irl.umsl.edu/bulletin/1087/thumbnail.jp
Navigating the Skies: An Exploration of Stakeholder Perspectives on Rules for Orbital Traffic Coordination using Grounded Theory and Case Study Research Methodologies
This dissertation explored standards, rules, or regulations ( rules ) of orbital traffic coordination to reduce the risk of collisions in space between active space objects. The research questions explored topics associated with areas for potential implementation of rules include maneuvering capabilities, liability and insurance, zoning, right-of-way, and tracking of objects in space.
The researcher utilized an exploratory qualitative research method because of the developing field of study and a growing domain for potential regulation. The research design is a mixture of a case study for bounding and structuring the data collection and grounded theory for a rigorous and well-defined analysis approach. The primary data source is semi-structured interviews used to explore the perspectives of three stakeholder groups with a vested interest in space traffic management. The three groups are space industry, space insurance industry, and space law and policy experts. Amongst the three groups, 19 interviews were conducted.
The data were analyzed to summarize and compare the different perspectives of each group and across the groups. From the summarized perspectives, the intent was to recommend a set of rules, but participants offered few specific rules. Instead, the dissertation’s results present shared considerations across the six research questions to provide the current state of thinking across the community.
Results from this dissertation will provide valuable insight to policymakers beyond feedback generally received during comment periods associated with federal rulemaking. National space traffic management legal frameworks need to harmonize globally to optimize space transportation operations and practices. This dissertation contributes to a larger global effort to standardize and solidify rules defining interactions between space operators by capturing the perspectives of experts primarily in and concerning the United States
Artificial Intelligence and International Conflict in Cyberspace
This edited volume explores how artificial intelligence (AI) is transforming international conflict in cyberspace. Over the past three decades, cyberspace developed into a crucial frontier and issue of international conflict. However, scholarly work on the relationship between AI and conflict in cyberspace has been produced along somewhat rigid disciplinary boundaries and an even more rigid sociotechnical divide – wherein technical and social scholarship are seldomly brought into a conversation. This is the first volume to address these themes through a comprehensive and cross-disciplinary approach. With the intent of exploring the question ‘what is at stake with the use of automation in international conflict in cyberspace through AI?’, the chapters in the volume focus on three broad themes, namely: (1) technical and operational, (2) strategic and geopolitical and (3) normative and legal. These also constitute the three parts in which the chapters of this volume are organised, although these thematic sections should not be considered as an analytical or a disciplinary demarcation
Engineering Blockchain Based Software Systems: Foundations, Survey, and Future Directions
Many scientific and practical areas have shown increasing interest in reaping
the benefits of blockchain technology to empower software systems. However, the
unique characteristics and requirements associated with Blockchain Based
Software (BBS) systems raise new challenges across the development lifecycle
that entail an extensive improvement of conventional software engineering. This
article presents a systematic literature review of the state-of-the-art in BBS
engineering research from a software engineering perspective. We characterize
BBS engineering from the theoretical foundations, processes, models, and roles
and discuss a rich repertoire of key development activities, principles,
challenges, and techniques. The focus and depth of this survey not only gives
software engineering practitioners and researchers a consolidated body of
knowledge about current BBS development but also underpins a starting point for
further research in this field
Responsible Composition and Optimization of Integration Processes under Correctness Preserving Guarantees
Enterprise Application Integration deals with the problem of connecting
heterogeneous applications, and is the centerpiece of current on-premise, cloud
and device integration scenarios. For integration scenarios, structurally
correct composition of patterns into processes and improvements of integration
processes are crucial. In order to achieve this, we formalize compositions of
integration patterns based on their characteristics, and describe optimization
strategies that help to reduce the model complexity, and improve the process
execution efficiency using design time techniques. Using the formalism of timed
DB-nets - a refinement of Petri nets - we model integration logic features such
as control- and data flow, transactional data storage, compensation and
exception handling, and time aspects that are present in reoccurring solutions
as separate integration patterns. We then propose a realization of optimization
strategies using graph rewriting, and prove that the optimizations we consider
preserve both structural and functional correctness. We evaluate the
improvements on a real-world catalog of pattern compositions, containing over
900 integration processes, and illustrate the correctness properties in case
studies based on two of these processes.Comment: 37 page
Exploring maintainability and performance in Ballerina Microservices
Microservices architecture currently is the industry norm for creating applications since it allows teams to focus on individual services related to specific business functionalities, reducing the overall application complexity and improving its maintainability. However, microservices architecture has liabilities regarding service integration, communication, governance, and data management. To solve these liabilities, the industry and academic community have focused on creating new frameworks and solutions. More recently, the focus changed to creating new programming languages focused on microservices. This study aims to investigate the effects of language-oriented approaches in developing microservices. The work focuses on Ballerina, a programming language created to simplify the creation and integration of microservices. From the literature’s analysis, Ballerina demonstrates the ability to be more beneficial than the most common implementations of microservices that use more common frameworks. To further investigate these statements, an experience based on the migration of existing microservices developed in Java with the use of the framework Spring Boot was conducted. This experience used a migration strategy created based on the language’s specificities. The resulting Ballerina microservice is compared with its original counterpart. The experience focused on analyzing both solutions in terms of maintainability and performance. Therefore, the Goals, Questions, Metrics (GQM) approach was used to obtain metrics for the mentioned quality attributes. From the obtained results, it was concluded that the Ballerina solution presents differences from the Spring Boot solution, being superior regarding maintainability and inferior in performance.A arquitetura baseada em microserviços atualmente é dentro da indústria considerada a norma para a criação de aplicações. A arquitetura baseada em microserviços apresenta diversas vantagens, como a possibilidade de distribuir as diferentes funcionalidades da aplicação por diversas equipas, possibilitando também o desenvolvimento dos seus serviços em linguagens de programação diferentes. Esta modularização traduz-se num acréscimo à independência das equipas, possibilitando a implementação dos seus próprios processos de trabalho como também reduz a complexidade total da aplicação, aumentando a sua manutenibilidade. Contudo, a arquitetura baseada em microserviços, dado o aumento na sua utilização, deu origem a novas questões e preocupações para as equipas de desenvolvimento e para as organizações. As equipas de desenvolvimento encontraram dificuldades na integração e comunicação dos seus serviços, principalmente quando estes eram desenvolvidos em linguagens de programação bastante divergentes. Apesar da modularidade e desacoplamento dos serviços, começou a ser detetada uma grande dependência com metodologias de implantação do código, onde o sucesso de microserviços encontrava-se fortemente dependente do uso de contentores e sistemas de orquestração. As organizações identificaram um aumento nos seus custos devido ao aumento de processos, armazenamento em servidores e de software para suporte às diversas equipas. Estas dificuldades advêm do facto de as linguagens de programação habitualmente usadas para a criação de microserviços não terem sido edificadas com o objetivo de suportar microserviços bem como não salvaguardam algumas das preocupações identificadas anteriormente. De forma a combater estas dificuldades, a indústria e a comunidade académica incidiram as suas investigações em novas frameworks e soluções. Recentemente, dado o novo foco na otimização para o "desenvolvimento", surgiram novas linguagens de programação orientadas a microserviços. Este estudo tem como objetivo investigar os efeitos da utilização de linguagens de programação orientadas a microserviços e subsequentemente a análise do seu impacto relativamente a atributos de qualidade relevantes para os mesmos. O foco deste estudo incidirá na linguagem de programação Ballerina, uma linguagem de programação criada com o intuito de facilitar a criação de serviços resilientes capazes de se integrarem e orquestrarem através de pontos de saída distribuídos. Foi realizada uma investigação à literatura existente sobre microserviços e sobre Ballerina, com especial atenção na literatura referente à utilização de Ballerina em microserviços. Esta investigação objetivou a identificação dos atributos de qualidade relevantes, de onde se precisou a manutenibilidade e a performance como sendo os atributos a avaliar. Derivada da análise da literatura, quando confrontada com implementações de linguagens de programação mais tradicionais, Ballerina demonstra a capacidade de proporcionar benefícios aquando da sua utilização em microserviços. Ballerina apresenta vantagens tais como o suporte nativo para a utilização de contentores, suporte a DevOps e funcionalidades focadas na segurança e resiliência das aplicações. De forma a aferir estas afirmações, foi efetuada uma experiência controlada baseada na migração de microserviços desenvolvidos na linguagem de programação Java com recurso à framework Spring Boot para a linguagem Ballerina. Para a realização desta experiência, primeiramente foi escolhido um projeto base do qual se realizaria a migração. O projeto a migrar teria de cumprir alguns requisitos, tais como: ser open-source, ter atividade recente e um número significativo de microserviços. Com base nestes requisitos, foi selecionado o projeto Lakeside Mutual, um projeto sobre uma companhia de seguros fictícia, desenvolvido com o propósito de demonstrar a utilização de padrões sobre APIs e design orientado ao domínio. Seguidamente, foi desenhada uma estratégia de migração com base nas especificidades da linguagem. Dada a implementação da estratégia, foi edificado um serviço em Ballerina à semelhança do original implementado em Java, mantendo todos os seus atributos e funcionalidades. As soluções foram comparadas em termos de manutenibilidade e performance, em que para tal foi utilizada a abordagem Goal, Question, Metrics (GQM) de forma a obter métricas para os atributos de qualidade previamente mencionados. Em termos de manutenibilidade, foram analisados os números de linhas de código existentes e a complexidade calculada através dos níveis de indentação dado que Ballerina ainda não suporta ferramentas como o Sonarqube. Relativamente à performance, foi desenhado e implementado um plano de testes com um número variado de utilizadores virtuais que executavam um conjunto de pedidos REST. Dos resultados obtidos, foi concluído que existem diferenças notáveis entre ambas as soluções. A solução em Ballerina apresenta melhores resultados do que a solução em Spring Boot relativamente à manutenibilidade. Contudo, relativamente à performance, a solução em Spring Boot demonstra obter melhores resultados
Digital Twins and Blockchain for IoT Management
We live in a data-driven world powered by sensors getting data from anywhere at any time. This advancement is possible thanks to the Internet of Things (IoT). IoT embeds common physical objects with heterogeneous sensing, actuating, and communication capabilities to collect data from the environment and people. These objects are generally known as things and exchange data with other things, entities, computational processes, and systems over the internet. Consequently, a web of devices and computational processes emerges involving billions of entities collecting, processing, and sharing data. As a result, we now have an internet of entities/things that process and produce data, an ever-growing volume that can easily exceed petabytes. Therefore, there is a need for novel management approaches to handle the previously unheard number of IoT devices, processes, and data streams.
This dissertation focuses on solutions for IoT management using decentralized technologies. A massive number of IoT devices interact with software and hardware components and are owned by different people. Therefore, there is a need for decentralized management. Blockchain is a capable and promising distributed ledger technology with features to support decentralized systems with large numbers of devices. People should not have to interact with these devices or data streams directly. Therefore, there is a need to abstract access to these components. Digital twins are software artifacts that can abstract an object, a process, or a system to enable communication between the physical and digital worlds. Fog/edge computing is the alternative to the cloud to provide services with less latency. This research uses blockchain technology, digital twins, and fog/edge computing for IoT management. The systems developed in this dissertation enable configuration, self-management, zero-trust management, and data streaming view provisioning from a fog/edge layer. In this way, this massive number of things and the data they produce are managed through services distributed across nodes close to them, providing access and configuration security and privacy protection
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