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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Green networking : analyses of power consumption of real and complex IFFT/FFT used in Next-Generation Networks and optical Orthogonal Frequency Division Multiplexing

Al-Obaidi, Sameer Sami Hassan January 2018 (has links)
The Orthogonal Frequency Division Multiplexing is a promising technology for the Next Generation Networks. This technique was selected because of the flexibility for the various parameters, high spectral efficiency, and immunity to ISI. The OFDM technique suffers from significant digital signal processing, especially inside the Inverse/ Fast Fourier Transform IFFT/FFT. This part is used to perform the orthogonality/De-orthogonality between the subcarriers which the important part of the OFDM system. Therefore, it is important to understand the parameter effects on the increase or to decrease the FPGA power consumption for the IFFT/FFT. This thesis is focusing on the FPGA power consumption of the IFFT/FFT uses in the OFDM system. This research finds a various parameters effect on FPGA power of the IFFT/FFT. In addition, investigate the computer software used to measure and analyse the FPGA power consumption of OFDM transceivers, and selects the target hardware used in the computer software. The researched parameters include the number of bits used in calculating the phase factor precision; Cyclic Prefix length effected on IP core IFFT, Subcarrier modulation type, word length width, Real and Complex Value IFFT, IFFT length, and subcarriers sampling frequency. The real value IFFT is proposed in 1987 and implemented in this thesis. These parameters above are discussed by comparing the result between the Real and Complex value IFFT used inside the OFDM system.
12

The Growth Potential of the 'Next-11': The Importance of Emerging Markets for Canadian Agrifood Trade

Cairns, Alexander Philip 16 September 2011 (has links)
The capacity of Canada’s export-oriented agrifood sectors to cope with contemporary challenges may hinge on their ability to identify new export markets. This thesis uses an import demand model, developed by Hallak (2006), to assess how per capita expenditure on Canadian agrifood exports is influenced by income growth and the presence of a preferential trade agreement for a group of emerging economies, known as ‘the Next-11.’ Results reveal that while as a group the Next-11 does not appear to be distinct from other income groups or the BRICs in terms of their expenditures on agrifood imports, Vietnam and South Korea demonstrate expenditure elasticities notably higher then other Next-11 and BRIC members. Finally, the findings cast doubt on the capacity of PTAs to enhance Canadian agrifood trade. However, this result may be indicative of Canada’s longstanding commitment to multilateral trade liberalization and the corresponding delay in the adoption of PTAs.
13

Long-Term Ongoing Structured Support in Early Stage of Dementia: A Family Affair

Kjällman Alm, Annika January 2014 (has links)
Demenssjukdomar drabbar mer än 35 miljoner människor världen över, en summa som kommer att fördubblas vart tjugonde år.    Demens är en global störning av intellektuella funktioner: förmågan att minnas försämras, och förmågor som att orientera sig i tid och rum, språklig förmåga, tankeprocesser som att gå från tanke till handling, problemlösande, utföra saker praktiskt och känna igen föremål. Symtomen följs ofta av förändringar i beteende och personlighet, som låg initiativförmåga, irritation, grovt socialt beteende och humörsvängningar. I Sverige diagnostiseras 25 000 personer per år, totalt så lever 160 000 personer med sjukdomen i Sverige idag. I Sverige ställs diagnosen ofta utifrån blodprover, hjärnröntgen och Mini Mental Score Evaluation-Swedish Revision tillsammans med personens sjukdomshistoria.   Efter diagnosen har ofta anhöriga många frågor om hur livet kommer att te sig framöver, är det bra att flytta eller ska man bo kvar? Hur kommer sjukdomen att förändra livet och personligheten hos den drabbade? Tidigare studier visar att dessa frågor ofta förblir obesvarade, det är svårt att få en uppföljning hos läkare och det finns få länder där stöd efter diagnosen är vanligt förekommande.    Sverige har sen 2009 lagstiftat om rätten till stöd till anhöriga och närstående med demenssjukdom eller andra kroniska sjukdomar med funktionshinder. Typen av stöd som ges skiljer sig däremot åt, Socialstyrelsen kom därför hösten 2013 ut med riktlinjer för hur stödet bör se ut för att vara effektivt: 8-10 träffar under 3-6 månader med information och socialt stöd till anhöriga. En kommun i norra delen av Sverige har gett långvarigt stöd till personer med demenssjukdom och deras anhöriga sen 2006. Ett nära samarbete med Landstinget i regionen och på senare tid även privata vårdcentraler i området har lett till att stöd kan erbjudas i direkt samband med diagnostillfället. Personerna deltar ofta i stödgrupp inom ca 4-6 veckor efter sin diagnos. Avhandlingens syfte var att fördjupa kunskapen om personernas upplevelse av att vara i stödgrupp under lång tid; den längsta i 4 år. Intervjuer gjordes med anhöriga och personer med demenssjukdom. Resultaten visade att de par som varit med längst i stödgrupp kände sig trygga, de upplevde att de fick god kunskap om demens och var förberedda på den förändring som skulle komma. Resultaten visade också att vara vuxet barn till en person med demens innebar att vara tyngd av ansvar för att agera i den sjuka förälderns intresse trots en djup känsla av sorg of förlust vilket ofta leder till frustration med situationen. Relationerna inom familjen kan förändras efter demens diagnosen både till det bättre; att man sluter upp kring den demenssjuke föräldern men också till det sämre; att familjen splittras då relationerna utsätts för påfrestningar. Personerna med demenssjukdom som deltog i stödgrupperna upplevde och skattade sin känsla av sammanhang högt; att livet var meningsfullt, begripligt och hanterbart. Deras friska partner upplevde mindre begriplighet och hanterbarhet och de vuxna barnen mer meningsfullhet. Avhandlingens resultat har legat till grund för en modell för stöd till personer med demenssjukdom och deras anhöriga kallat PER-modellen®; Pedagogisk, Emotionell och Relationsbaserad modell för stöd. / Dementia disorders affect more than 35 million people around the world, which will double every twenty years. Dementia is a global disruption of intellectual functioning; there is a decrease of memory ability and other intellectual abilities such as orientation, visuospatial- perceptive ability, language, thinking, executive abilities, problem solving, apraxia and agnosia.  These symptoms are often followed by behavioral changes and changes in the personality, such as loss of initiative, emotional instability, irritation, apathy, coarse social behaviour and mood changes. The most frequent symptoms were apathy, depression, irritability, and agitation. About 25, 000 persons are diagnosed with dementia each year in Sweden. Today, estimates are that 160, 000 persons in total are suffering from dementia in Sweden. In Sweden, most diagnoses are done in the primary health care setting by general practitioners  and are based on the person´s own history, interviews with next of kin and an Mini Mental Score Evaluation- Swedish Revision (MMSE-SR) along with blood work and a brain scan to rule out any other diseases. After diagnosis the next of kin often have many questions about the coming lifestyle changes and ways to handle the personality changes that the person suffering from dementia may go through. Previous studies show that in many cases these questions are left unanswered, because it is difficult to get a follow up with a physician and there are few countries where support after diagnose is common.    In 2009, the Swedish Parliament passed a new law that states that support is to be given to persons caring for people with chronic illnesses, elderly people, or people with functional disabilities. There was, however, no detailed description of the extent or kind of services to be provided, and the municipalities had extensive freedom in implementing the legislation. In the autumn of 2013 the Swedish National Health Board therefore, issued guidelines where eight to ten meetings during a three- to six-month period with information and social support were recommended.A municipality in northern Sweden have a long term ongoing support to persons with dementia and their next of kin since 2006. A close collaboration with the geriatric clinic and private health centers has resulted in support being offered within 4-6 weeks after diagnose.     The overall aim of this thesis was to explore experiences of living with dementia both as a sufferer and as a next of kin; and being part of a long-term ongoing support group, the longest for four years.     Interviews were done with persons with dementia and their next of kin. Results showed that couples who had been the longest in a support group felt great comfort and support. They experienced that their knowledge about the disorder was good and that they could prepare for the changes to come. Results also showed that to be an adult child of a person with dementia disease means being burdened with the responsibility to act on behalf of the diseased parent despite a deep sense of grief and loss, which leads to frustration with the situation.     Relationships within the family can sometimes change when a family member is affected by dementia. Sometimes for the better; where the family rallied to support the affected member and sometimes for worse; where the relationships were strained when pressure became too much. The persons with dementia who participated in the support groups experienced a great sense of coherence and felt that life was manageable, comprehensible and meaningful. Their healthy partners experienced less comprehensibility and manageability and the adult children more meaningfulness.   The results of the thesis have founded a model for support called PER-model®; Pedagogical, Emotional and Relationship based model of support.
14

Using next generation sequencing to investigate the generation of diversity in the genus Begonia

Emelianova, Katie January 2017 (has links)
Begonia is one of the most diverse genera on the planet, with a species count approaching 2000 and a distribution across tropics in South America, Africa and South East Asia. The genus has occupied a vast range of niches; many highly variable growth forms can be found across the distribution, and species exhibit very diverse morphologies, even in closely related species. A recent study has revealed a putative whole genome duplication (WGD) event in the evolutionary history of Begonia, which has prompted an interest in investigating the impact gene and genome duplication has had on the diversification of Begonia. To answer questions about phenotypic and ecological diversification in Begonia, two species from South America, B. conchifolia and B. plebeja were chosen as study species based on their close phylogenetic relationship and divergent ecology and phenotype. RNA-seq data for six tissues from B. conchifolia and B. plebeja was generated using the Illumina sequencing platform, and normalised relative expression data was obtained by mapping reads to transcripts predicted from the B. conchifolia draft genome. A bioinformatics pipeline was devised to compare expression profiles across 6 different tissues between duplicated gene pairs shared between B. conchifolia and B. plebeja. Gene duplicate pairs were selected as candidates if they showed divergent expression in one species but not in another. Such duplicate pairs are suggestive of neofunctionalization in one species, providing evidence of a potential basis for phenotypic divergence and diversification between B. conchifolia and B. plebeja. Two duplicate pairs were identified as showing such divergent expression patterns as well as being functionally ecologically relevant, Chalcone Synthase and 3-Ketoacyl-CoA synthase, involved in anthocyanin biosynthesis and wax biosynthesis respectively. Investigation of expression and duplication patterns in both gene families showed the candidate gene families to be strikingly different. While 3-Ketoacyl-CoA synthase showed deeper duplications shared with outgroup taxa, Chalcone Synthase appeared to be expanded very recently, with a burst of duplications specific to the genus. 3-Ketoacyl-CoA synthase showed examples of partitioned expression by tissue for different gene family members, with at least five members of the gene family being highly expressed in one or two tissues only. Chalcone Synthase, however, showed dominance of one basal gene family member. Other Chalcone Synthase members, though expressed at lower levels, showed some evidence of reciprocal silencing in B. plebeja, though this pattern was not observed in B. conchifolia. Further investigation of the Chalcone Synthase gene family revealed lineage specific duplication in B. plebeja, and more extensive differential duplication patterns were found across other South American Begonias. Additionally, signals of positive selection were found in two branches on the Chalcone Synthase phylogeny.
15

SOUTHERN ILLINOIS GIS MAPPING FOR NEXT GENERATION 9-1-1

Barrett, William Lee 01 December 2012 (has links)
Next Generation 9-1-1 (NG 9-1-1) will revolutionize how the public accesses emergency services and will alter the technological landscape within which existing public safety agencies operate. A lack of systematic methodologies exists for quality control of the required geospatial data layers for NG 9-1-1 systems. The primary objective of this study was to develop and systematize a highly accurate NG 9-1-1 GIS database for Counties of Southern Illinois (CSI). The project goals included mapping relevant geospatial data layers required by and based on NENA standard data formats; conducting data quality control and standardization; and providing standardized spatial datasets for NG 9-1-1 to relevant stakeholders. The approach was developed using a conceptual model for error and uncertainty analysis of the GIS-based NG 9-1-1 system. This included the identification of various sources of input uncertainties often associated with spatial data layers; modeling the accumulation and propagation of errors; analyzing their impact on the quality of the spatial data layers; and correcting the errors. Modeling uncertainty propagation focused on positional errors and was conducted through a simulation procedure. The results showed that the original spatial datasets possessed a large account of uncertainties, especially location errors of railroads and roads. The errors had different sources, including input map errors, the use of different map projection and coordinate systems, a lack of topological structures, etc. In addition, they varied from county to county. From the error propagation simulation, it was also found that the location errors measured as root mean square error (RMSE) fluctuated when the perturbed distance of the ground control points (GCP) was less than 15 m. After that, the RMSE increased as the perturbed distance of GCPs increased. This relationship was significantly linear. In addition, the location errors from railroads were larger than those from roads.
16

UTILIZAÇÃO da Bioinformática na Busca de Novos Genes em Osteogênese Imperfeita

COUTINHO, A. S. 26 February 2018 (has links)
Made available in DSpace on 2018-08-01T21:35:03Z (GMT). No. of bitstreams: 1 tese_12056_Dissertação_Amanda Silva Coutinho.pdf: 1166104 bytes, checksum: f4756c682c195491abc65c33b3ce87fc (MD5) Previous issue date: 2018-02-26 / A osteogênese imperfeita (OI) é uma doença genética rara do tecido conjuntivo, causada por mutações em genes que participam, em geral, da formação óssea. A maioria dos pacientes é portadora de mutações nos genes que codificam o colágeno tipo 1, mas já foram descritas mutações em mais de 17 outros genes causando OI e ainda existe uma busca constante de novos genes na área cientifica. Entre as estratégias de diagnóstico molecular destaca-se a técnica de sequenciamento de nova geração (NGS), que pode sequenciar vários genes presentes em uma plataforma customizada, gerando uma grande quantidade de dados genômicos. Esses dados se tornam preciosas fontes de informação na busca de novos genes relacionados a doenças. O objetivo desta pesquisa foi realizar a busca de novos genes potencialmente causadores de OI por meio de recursos de bioinformática. Foram utilizadas estratégias de filtragem pelo programa Microsoft Office Excel 2013, bem como análises de predição de mutação. Como referência genômica foram utilizados os bancos de dados Ensembl e National Center for Biotechnology Information. Foram selecionados quatro pacientes diagnosticados clinicamente com OI que foram submetidos à técnica de NGS e apresentaram resultados normais para os genes conhecidos. Com o intuito de selecionar uma lista de genes candidatos na plataforma customizada de NGS que estivessem relacionados com os sintomas de OI, foi realizada uma busca de genes no banco de dados Ensembl envolvidos com as vias metabólicas de formação óssea, cartilaginosa ou de colágeno, que identificou 643 genes. A lista de genes candidatos foi comparada com os genes sequenciados dos pacientes, onde foram selecionados 70 genes em comum para análise. Foram realizadas filtragens in silico de forma a selecionar alterações raras na população, preditas como patogênicas e que efetivamente codifiquem uma proteína ou uma molécula de RNA funcional. Os resultados mostraram que o paciente P.1 é portador de uma mutação em heterozigose potencialmente patogênica no gene ALX1. O paciente P.2 apresentou apenas uma alteração no gene COL6A3 que foi predita como polimorfismo. O paciente P.3 apresentou mutações patogênicas em heterozigose nos genes ALPL e FKBP10. No paciente P.4 foram encontradas mutações patogênicas em heterozigose nos genes P3H1 e RYR1. Entre os cinco genes identificados, sabe-se que dois deles, FKBP10 e P3H1, estão relacionados com a OI de herança autossômica recessiva. Também já é descrito que mutações no gene ALPL causam sintomas clínicos semelhantes a OI, podendo confundir o diagnóstico. Assim, o presente estudo identificou dois genes, ALX1 e RYR1, potencialmente causadores de OI. O gene ALX1 tem um papel importante no desenvolvimento craniano e dos membros, pois atua na formação da cartilagem. Já o RYR1 codifica a rianodina, um importante receptor de cálcio nos osteoblastos. Estudos funcionais dos genes identificados são necessários para validar esta hipótese em pesquisas futuras. Os resultados deste trabalho sugerem que ferramentas de bioinformática podem direcionar a busca por novos genes relacionados a doenças genéticas. A caracterização de novas mutações em genes relacionados com OI auxilia no planejamento de estratégias mais eficientes que permitam o diagnóstico molecular da doença e o aconselhamento genético.
17

Integrated approaches to elucidate the genetic architecture of congenital heart defects

Al Turki, Saeed January 2014 (has links)
Congenital heart defects (CHD) are structural anomalies affecting the heart, are found in 1% of the population and arise during early stages of embryo development. Without surgical and medical interventions, most of the severe CHD cases would not survive after the first year of life. The improved health care for CHD patients has increased CHD prevalence significantly, and it has been estimated that the population of adults with CHD is growing ~5% per year. Understanding the causes of CHD would greatly help improve our knowledge of the pathophysiology, family counseling and planning and possibly prevention and treatment in the future. The aim of my thesis was to identify novel or known CHD genes enriched for rare coding genetic variants in isolated CHD cases and learn about the relative performance of different study designs. High-throughput next generation sequencing (NGS) was used to sequence all coding genes (whole exome) coupled with various analytical pipelines and tools to identify candidate genes in different family-based study designs. Since there is no general consensus on the underlying genetic model of isolated CHD, I developed a suite of software tools to enable different family-based exome analyses of de novo and inherited variants (chapter 2) and then piloted these tools in several gene discovery projects where the mode of inheritance was already known to identify previously described and novel pathogenic genes, before applying them to an analysis of families with two or more siblings with CHD. Based on the tools developed in chapter 2, I designed a two-stage study to investigate isolated parent-offspring trios with Tetralogy of Fallot (chapter 3). In the first stage, I used whole exome sequence data from 30 trios to identify genes with de novo coding variants. This analysis identified six de novo loss-of-function and 13 de novo missense variants. Only one gene showed recurrent de novo mutations in NOTCH1, a well known CHD gene that has mostly been associated with left ventricle outflow tract malformations (LVOT). Besides NOTCH1, the de novo analysis identified several possibly pathogenic novel genes such as ZMYM2 and ARHGAP35, that harbor de novo loss-of-function variants (frameshift and stop gain, respectively). In the second stage of the study, I designed custom baits to capture 122 candidate genes for additional sequencing using NGS in a larger sample size of 250 parent-offspring trios with isolated Tetralogy of Fallot and identified six de novo variants in four genes, half of them are loss-of-function variants. Both of NOTCH1 and its ligand JAG1 harbor two additional de novo mutations (two stop gains in NOTCH1 and one missense and a splice donor in JAG1). The analysis showed a strongly significant over-representation of de novo loss-of-function variants in NOTCH1 (P=3.8 ×10-9). To assess alternative family-based study design in CHD, I combined the analysis from 13 isolated parent-offspring trios with 112 unrelated index cases of isolated atrioventricular septal defects (AVSD) in chapter 4. Initially, I started with a case/control analysis to test the burden of rare missense variants in cases compared with 5,194 ethnically matching controls and identified the gene NR2F2 (Fisher exact test P=7.7×10-07, odds ratio=54). The de novo analysis in the AVSD trios identified two de novo missense variants in the same gene. NR2F2 encodes a pleiotropic developmental transcription factor, and decreased dosage of NR2F2 in mice has been shown to result in abnormal development of atrioventricular septa. The results from luciferase assays show that all coding sequence variants observed in patients significantly alter the activity of NR2F2 target promoters. My work has identified both known and novel CHD genes enriched for rare coding variants using next-generation sequencing data. I was able to show how using single or combined family-based study designs is an effective approach to study the genetic causes of isolated CHD subtypes. Despite the extreme heterogeneity of CHD, combining NGS data with the proper study design has proved to be an effective approach to identify novel and known CHD genes. Future studies with considerably larger sample sizes are required to yield deeper insights into the genetic causes of isolated CHD.
18

Přínos Next Generation Sequencing pro laboratorní diagnostiku / Contribution of Next Generation Sequencing for Laboratory Diagnostics

Votýpka, Pavel January 2015 (has links)
5 ABSTRACT Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Pavel Votýpka Supervisor: Doc. PharmDr. Martin Beránek, Ph.D. Consultant: Mgr. Nikola Ptáková Title of diploma thesis: Contribution of Next Generation Sequencing for Laboratory Diagnostics The endeavor to sequence the whole human genome lead not only to the knowledge acquisition regarding the human genetic information but as well to the development of new sequencing methods and technologies. In order to keep up with progress in genetic field in many clinical and research laboratories the new massive parallel sequencing equipment is being utilized. On the market are currently established four leading platforms - Illumina, Solid, Ion Torrent and 454 Life Technologies. The process of sequencing analysis can be summarized into three main steps - the sequencing library preparation, sequencing itself, variant calling and data analysis. Each part of the sequencing analysis exhibits certain specifics, we need to count with and as well its pitfalls, we need to avoid or to minimalize their impact on the analysis final result. Recently new methods termed sequencing of the 3rd generation are being developed, enabling sequence of a single DNA molecule to be determined without previous...
19

The Desugn of MACPAC - A Graphics Subroutine Library Based on a Design Philosophy for the Next Generation of Graphics Packages

Vrenjak, Helen 10 1900 (has links)
This paper presents the design of a graphics subroutine library, MacPac, as a contribution to the development of a standard for future graphics packages. The need for a new graphics standard, and hence the motivation for the development of MacPac, is illustrated through a detailed discussion of existing graphics standards and systems. MacPac is based on a design philosophy developed by Mark Green for the next generation of graphics packages. It addresses the hardware and software ideas of the 80's, incorporating and building upon the valuable and tested ideas of a number of existing graphics systems. The design languages used in the development of MacPac were created by Mark Green for the design of user interfaces. This work examines the effectiveness of these languages in the design of a graphics system. / Thesis / Master of Science (MS)
20

Design of Secure Scalable Frameworks for Next Generation Cellular Networks

Atalay, Tolga Omer 06 June 2024 (has links)
Leveraging Network Functions Virtualization (NFV), the Fifth Generation (5G) core, and Radio Access Network (RAN) functions are implemented as Virtual Network Functions (VNFs) on Commercial-off-the-Shelf (COTS) hardware. The use of virtualized micro-services to implement these 5G VNFs enables the flexible and scalable construction of end-to-end logically isolated network fragments denoted as network slices. The goal of this dissertation is to design more scalable, flexible, secure, and visible 5G networks. Thus, each chapter will present a design and evaluation that addresses one or more of these aspects. The first objective is to understand the limits of 5G core micro-service virtualization when using lightweight containers for constructing various network slicing models with different service guarantees. The initial deployment model consists of the OpenAirInterface (OAI) 5G core in a containerized setting to create a universally deployable testbed. Operational and computational stress tests are performed on individual 5G core VNFs where different network slicing models are created that are applicable to real-life scenarios. The analysis captures the increase in compute resource consumption of individual VNFs during various core network procedures. Furthermore, using different network slicing models, the progressive increase in resource consumption can be seen as the service guarantees of the slices become more demanding. The framework created using this testbed is the first to provide such analytics on lightweight virtualized 5G core VNFs with large-scale end-to-end connections. Moving into the cloud-native ecosystem, 5G core deployments will be orchestrated by middle-men Network-slice-as-a-Service (NSaaS) providers. These NSaaS providers will consume Infrastructure-as-a-service (IaaS) offerings and offer network slices to Mobile Virtual Network Operators (MVNOs). To investigate this future model, end-to-end emulated 5G deployments are conducted to offer insight into the cost implications surrounding such NSaaS offerings in the cloud. The deployment features real-life traffic patterns corresponding to practical use cases which are matched with specific network slicing models. These models are implemented in a 5G testbed to gather compute resource consumption metrics. The obtained data are used to formulate infrastructure procurement costs for popular cloud providers such as Amazon Web Services (AWS), Google Cloud Platform (GCP), and Microsoft Azure. The results show steady patterns in compute consumption across multiple use cases, which are used to make high-scale cost projections for public cloud deployments. In the end, the trade-off between cost and throughput is achieved by decentralizing the network slices and offloading the user plane. The next step is the demystification of 5G traffic patterns using the Over-the-Air (OTA) testbed. An open-source OTA testbed is constructed leveraging advanced features of 5G radio access and core networks developed by OAI. The achievable Quality of Service (QoS) is evaluated to provide visibility into the compute consumption of individual components. Additionally, a method is presented to utilize WiFi devices for experimenting with 5G QoS. Resource consumption analytics are collected from the 5G user plane in correlation to raw traffic patterns. The results show that the open-source 5G testbed can sustain sub-20ms latency with up to 80Mbps throughput over a 25m range using COTS devices. Device connection remains stable while supporting different use cases such as AR/VR, online gaming, video streaming, and Voice-over IP (VoIP). It illustrates how these popular use cases affect CPU utilization in the user plane. This provides insight into the capabilities of existing 5G solutions by demystifying the resource needs of specific use cases. Moving into public cloud-based deployments, creates a growing demand for general-purpose compute resources as 5G deployments continue to expand. Given their existing infrastructures, cloud providers such as AWS are attractive platforms to address this need. Therefore, it is crucial to understand the control and user plane QoS implications associated with deploying the 5G core on top of AWS. To this end, a 5G testbed is constructed using open-source components spanning multiple global locations within the AWS infrastructure. Using different core deployment strategies by shuffling VNFs into AWS edge zones, an operational breakdown of the latency overhead is conducted for 5G procedures. The results show that moving specific VNFs into edge regions reduces the latency overhead for key 5G operations. Multiple user plane connections are instantiated between availability zones and edge regions with different traffic loads. As more data sessions are instantiated, it is observed that the deterioration of connection quality varies depending on traffic load. Ultimately, the findings provide new insights for MVNOs to determine favorable placements of their 5G core entities in the cloud. The transition into cloud-native deployments has encouraged the development of supportive platforms for 5G. One such framework is the OpenRAN initiative, led by the O-RAN Alliance. The OpenRAN initiative promotes an open Radio Access Network (RAN) and offers operators fine-grained control over the radio stack. To that end, O-RAN introduces new components to the 5G ecosystem, such as the near real-time RAN Intelligent Controller (near-RT RIC) and the accompanying Extensible Applications (xApps). The introduction of these entities expands the 5G threat surface. Furthermore, with the movement from proprietary hardware to virtual environments enabled by NFV, attack vectors that exploit the existing NFV attack surface pose additional threats. To deal with these threats, the textbf{xApp repository function (XRF)} framework is constructed for scalable authentication, authorization, and discovery of xApps. In order to harden the XRF microservices, deployments are isolated using Intel Software Guard Extensions (SGX). The XRF modules are individually benchmarked to compare how different microservices behave in terms of computational overhead when deployed in virtual and hardware-based isolation sandboxes. The evaluation shows that the XRF framework scales efficiently in a multi-threaded Kubernetes environment. Isolation of the XRF microservices introduces different amounts of processing overhead depending on the sandboxing strategy. A security analysis is conducted to show how the XRF framework addresses chosen key issues from the O-RAN and 5G standardization efforts. In the final chapter of the dissertation, the focus shifts towards the development and evaluation of 5G-STREAM, a service mesh tailored for rapid, efficient, and authorized microservices in cloud-based 5G core networks. 5G-STREAM addresses critical scalability and efficiency challenges in the 5G core control plane by optimizing traffic and reducing signaling congestion across distributed cloud environments. The framework enhances Virtual Network Function (VNF) service chains' topology awareness, enabling dynamic configuration of communication pathways which significantly reduces discovery and authorization signaling overhead. A prototype of 5G-STREAM was developed and tested, showing a reduction of up to 2× in inter-VNF latency per HTTP transaction in the core network service chains, particularly benefiting larger service chains with extensive messaging. Additionally, 5G-STREAM's deployment strategies for VNF placement are explored to further optimize performance and cost efficiency in cloud-based infrastructures, ultimately providing a scalable solution that can adapt to increasing network demands while maintaining robust service levels. This innovative approach signifies a pivotal advancement in managing 5G core networks, paving the way for more dynamic, efficient, and cost-effective cellular network infrastructures. Overall, this dissertation is devoted to designing, building, and evaluating scalable and secure 5G deployments. / Doctor of Philosophy / Ever since the emergence of the Global System for Mobile Communications (GSM), humanity has relied on cellular communications for the fast and efficient exchange of information. Today, with the Fifth Generation (5G) of mobile networks, what may have passed for science fiction 40 years ago, is now slowly becoming reality. In addition to enabling extremely fast data rates and low latency for user handsets, 5G networks promise to deliver a very rich and integrated ecosystem. This includes a plethora of interconnected devices ranging from smart home sensors to Augmented/Virtual Reality equipment. To that end, the stride from the Fourth Generation (4G) of mobile networks to 5G is yet to be the biggest evolutionary step in cellular networks. In 4G, the backbone entities that glued the base stations together were deployed on proprietary hardware. With 5G, these entities have been moved to Commercial off-the-shelf (COTS) hardware which can be hosted by cloud providers (e.g., Amazon, Google, Microsoft) or various Small to Medium Enterprises (SMEs). This substantial paradigm shift in cellular network deployments has introduced a variety of security, flexibility, and scalability concerns around the deployment of 5G networks. Thus, this thesis is a culmination of a wide range of studies that seek to collectively facilitate the secure, scalable, and flexible deployment of 5G networks in different types of environments. Starting with small-scale optimizations and building up towards the analysis of global 5G deployments, the goal of this work is to demystify the scalability implications of deploying 5G networks. On this journey, several security flaws are identified within the 5G ecosystem, and frameworks are constructed to address them in a fluent manner.

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