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Improving Object-Oriented Programming by Integrating Language Features to Support Immutability
Get PDFNowadays developers consider Object-Oriented Programming (OOP) the de-facto general programming paradigm. While successful, OOP is not without problems. In 1994, Gamma et al. published a book with a set of 23 design patterns addressing recurring problems found in OOP software. These patterns are well-known in the industry and are taught in universities as part of software engineering curricula. Despite their usefulness in solving recurring problems, these design patterns bring a certain complexity in their implementation. That complexity is influenced by the features available in the implementation language. In this thesis, we want to decrease this complexity by focusing on the problems that design patterns attempt to solve and the language features that can be used to solve them. Thus, we aim to investigate the impact of specific language features on OOP and contribute guidelines to improve OOP language design.
We first perform a mapping study to catalogue the language features that have been proposed in the literature to improve design pattern implementations. From those features, we focus on investigating the impact of immutability-related features on OOP.
We then perform an exploratory study measuring the impact of introducing immutability in OOP software with the objective of establishing the advantages and drawbacks of using immutability in the context of OOP. Results indicate that immutability may produce more granular and easier-to-understand programs.
We also perform an experiment to measure the impact of new language features added into the C\# language for better immutability support. Results show that these specific language features facilitate developers' tasks when aiming to implement immutability in OOP.
We finally present a new design pattern aimed at solving a problem with method overriding in the context of immutable hierarchies of objects. We discuss the impact of language features on the implementations of this pattern by comparing these implementations in different programming languages, including Clojure, Java, and Kotlin.
Finally, we implement these language features as a language extension to Common Lisp and discuss their usage
Performance Modeling of Vehicular Clouds Under Different Service Strategies
Get PDFThe amount of data being generated at the edge of the Internet is rapidly rising as a result of the Internet of Things (IoT). Vehicles themselves are contributing enormously to data generation with their advanced sensor systems. This data contains contextual information; it's temporal and needs to be processed in real-time to be of any value. Transferring this data to the cloud is not feasible due to high cost and latency. This has led to the introduction of edge computing for processing of data close to the source. However, edge servers may not have the computing capacity to process all the data. Future vehicles will have significant computing power, which may be underutilized, and they may have a stake in the processing of the data. This led to the introduction of a new computing paradigm called vehicular cloud (VC), which consists of interconnected vehicles that can share resources and communicate with each other. The VCs may process the data by themselves or in cooperation with edge servers.
Performance modeling of VCs is important, as it will help to determine whether it can provide adequate service to users. It will enable determining appropriate service strategies and the type of jobs that may be served by the VC such that Quality of service (QoS) requirements are met. Job completion time and throughput of VCs are important performance metrics. However, performance modeling of VCs is difficult because of the volatility of resources. As vehicles join and leave the VC, available resources vary in time. Performance evaluation results in the literature are lacking, and available results mostly pertain to stationary VCs formed from parked vehicles. This thesis proposes novel stochastic models for the performance evaluation of vehicular cloud systems that take into account resource volatility, composition of jobs from multiple tasks that can execute concurrently under different service strategies. First, we developed a stochastic model to analyze the job completion time in a VC system deployed on a highway with service interruption. Next, we developed a model to analyze the job completion time in a VC system with a service interruption avoidance strategy. This strategy aims to prevent disruptions in task service by only assigning tasks to vehicles that can complete the tasks’ execution before they leave the VC. In addition to analyzing job completion time, we evaluated the computing capacity of VC systems with a service interruption avoidance strategy, determining the number of jobs a VC system can complete during its lifetime. Finally, we studied the computing capacity of a robotaxi fleet, analyzing the average number of tasks that a robotaxi fleet can serve to completion during a cycle. By developing these models, conducting various analyses, and comparing the numerical results of the analyses to extensive Monte Carlo simulation results, we gained insights into job completion time, computing capacity, and overall performance of VC systems deployed in different contexts
Development of a Tablet-Based Sensor for Point-of-Care Analyses Utilizing Pullulan-Stabilized Gold Nanoparticles
No full textThe quickly expanding fields of nanotechnology and engineered nanomaterials helped solve serious issues that environments and human health suffer from for a long period of time. By accelerating the diagnoses and providing portable sensors that enable the demarcation of processes in biological systems to a previously unattainable degree, this nanotechnology will have an impact on clinical research and the detection of many analytes.
Tablet-based sensors have emerged as a powerful tool for point-of-care analyses, revolutionizing the way healthcare professionals diagnose and monitor patients. These sensors, when integrated with tablets, offer numerous advantages and play a crucial role in enhancing healthcare delivery. This advancement in tablet-based sensors for point-of-care analyses should include features such as; enabling healthcare professionals to conduct rapid and accurate diagnostics of various biomarkers, pathogens, and diseases by providing instant results. This real-time information allows for timely interventions and treatment decisions, reducing the need for sending samples to a laboratory and waiting for results, which can lead to delays in treatment. Importantly, the portability and compactness of tablets are highly required especially in remote or resource-limited settings. Furthermore, tablet-based sensors offer a cost-effective alternative to traditional laboratory-based diagnostics where the need for expensive laboratory equipment is eliminated, reducing the overall cost of diagnostics.
Additionally, portable tablet sensors do not require training, enabling healthcare professionals to perform tests without extensive specialized expertise. Notably, patients can interact with the sensors and see the results in real-time, empowering them to actively participate in their healthcare. This engagement fosters better patient-provider communication, improves treatment adherence, and increases patient satisfaction. Finally, tablet-based sensors not only aid in diagnostics but also facilitate continuous monitoring of patients by tracking vital signs, glucose levels, and drug concentrations. This routine monitoring helps healthcare professionals make informed decisions, promptly adjust treatments, prevent health complications, and save the lives of millions of people.
Following nanotechnology and based on encapsulation of materials, in this work the fabrication of pullulan stabilized gold nanoparticles tablet (AuNPs-pTab) was used as a point-of-care (POC) analytical device utilizing pullulan-AuNPs solution (AuNPs-pSol) without the need for any extra ingredients, which were subsequently used as colorimetric sensors for glucose and cysteamine detection in human saliva and serum samples, respectively. This newly offered AuNPs-pTab sensor has demonstrated excellent peroxidase-like activity and gives an easy substitute for AuNPs solution with enhanced catalytic efficiency. Additionally, the AuNPs-pTab sensor is a promising platform for point-of-care devices due to its fulfillment of RE-ASSURED criteria (Real-time, Ease of specimen collection, Affordable, Sensitive, Specific, User-friendly, Rapid and robust, Equipment-free, and Deliverable to end users) which is considered of great importance in the field of diagnosis and detection. AuNPs-pTab sensor is an attractive tool that has the potential to open a new horizon in disease diagnosis due to its functionality in H2O2 detection which is a possible biomarker for many diseases. Even though a range of nanozymes has been reported to date for their enzyme-mimicking catalytic activity as a solution-based sensor. However, in remote areas, the need for portable, cost-effective, and one-pot preparation is extremely demanding. Therefore, this work is appealing to researchers working in nanotechnology, and the advancement of innovative portable bioassays as well as point-of-care devices
Arithmetic Biases for Binary Quadratic Forms
Get PDFThe prime number theorem for arithmetic progressions tells us that there are asymptotically as many primes congruent to as there are congruent to . That being said, Chebyshev noticed that (numerically) there almost always seems to be slightly more primes congruent to . This simple fact has a highly non-trivial explanation. Rubinstein and Sarnak proved that the assumption of some natural (yet still unproven) conjectures, there is a way to prove that there are more primes congruent to than congruent to more than half of the time (in an appropriate sense).
Many other sets of integers demonstrate a bias towards a certain residue class modulo some number . Recently, Gorodetsky showed that the sums of two squares exhibit a Chebyshev-type bias, and that in this case the conjectures one must assume to prove the existence of the bias are weaker. In this thesis, we present two papers which demonstrate some bias in arithmetic progressions for sets of integers that are represented by a given binary quadratic form.
In Chapter 2, we examine a bias towards the zero residue class for the integers represented by binary quadratic forms. In many cases, we are able to prove that the bias comes from a secondary term in the associated asymptotic expansion (unlike Chebyshev's bias, which lives somewhere at the level of .) In some other cases, we are unable to prove that a bias exists, even though it is present numerically. We then make a conjecture on the general situation which includes the cases we could not prove. Many interesting results on the distribution of the integers represented by a quadratic form are proven, and the paper finishes with some numerical data that is illustrative of the generic data for any quadratic form.
In Chapter 3, we examine a different kind of bias. We ask for the distribution of pairs of sums of two squares in arithmetic progressions, i.e. how many numbers are the sum of two squares, congruent to , and are such that the next largest sum of two squares is congruent to . We prove that when , we have equidistribution among the possible pairs of residue classes. That being said, there exist bizarre numerical biases, most notably a negative bias towards repetition. The main purpose of the second paper is to provide a conjecture which explains the bias, via a secondary and tertiary term in the associated asymptotic expansion. We then support this conjecture with both numerical and theoretical evidence. The paper contains many partial results in the direction of the conjecture, as well as some theorems on the sums of two squares that are of independent interest. For example, we provide an integral representation for the number of integers not exceeding which are the sum of two squares. This integral representation is akin to for primes, in that it has a error term under the Generalized Riemann Hypothesis
A Shadow Cannot Feel Pain: Meditations on the Human Emotions & Suffering of Christ
Get PDFThe Western world is currently undergoing a mass destigmatization regarding the issues of mental health - societal ideas of masculinity and femininity, definitions of weakness, the blemish of seeking help, and the complexities of personal identity are being tossed on their heads in favour of a push toward acceptance and personal liberation, with help at the ready. With that in mind, this thesis argues that the character of Jesus Christ can be recontextualized through the example of his own mental health struggles as a figure by which to model oneself in an effort to navigate the tumults of suffering. The patristic theologian, Cyril of Alexandria, in response to the Nestorian Controversy, galvanizes the necessary human nature of Christ - a nature that is witnessed most keenly in the biblical scene of the Garden of Gethsemane, where Christ underwent emotions of doubt, fear, and temptation. Cyril's own ideas on an emotional human Christ, an individual that bore the full extent of the human soul, can be further explicated by the 19th century Danish philosopher, Søren Kierkegaard. Though Kierkegaard doesn't single-out Cyril, nor indeed Christ, his explorations into the liberational components of anxiety illuminate how Christ's anxiety, as well as our own, might serve as an orientation toward faith. More contemporary theologians, such as Bernard Lonergan and John D. Caputo, understand this liberation as a way in which to extract and adjoin meaning to that faith. By witnessing this process in Jesus: an understanding of his human nature, anxiety leading to faith, and the appearance of meaning and purpose, the individual might then use the model of Christ, a contemporary imitatio christi, as a way to understand, witness, and assign meaning to their own suffering
A Machine Learning Approach for Generating a Recursive Object Model from a Natural Language Text
Get PDFThis research investigates the potential of machine learning algorithms as an alternative approach to rule-based systems for generating Recursive Object Model (ROM) diagrams. The existing rule-based approach suffers from limitations and challenges, and this study aims to explore the possibility of overcoming these limitations by leveraging machine learning techniques.
To achieve the research objectives, software was developed to gather labelled data for our supervised learning problem. A model comprised of Multilayer Perceptron (MLP) and Long Short-Term Memory (LSTM) models was created and trained using the labelled data. The proposed model takes a pair of words and a sentence as inputs and classifies the appropriate relations among the pairs. Subsequently, a comprehensive evaluation was conducted to assess the effectiveness of the proposed model.
The evaluation process involved a comparative analysis between the proposed model and a baseline model, an evaluation of the proposed model on unseen data, and an investigation into the capability of the design model in addressing the limitations of the rule-based system. The evaluation results demonstrate the superiority of the proposed model. Firstly, the proposed model achieved an exceptional accuracy of 97 percent in the training process, surpassing the baseline model's accuracy of approximately 61 percent. Secondly, the proposed model exhibited an accuracy of 96 percent on unseen data, thus showcasing its ability to generalize effectively to new instances. Lastly, when comparing the proposed intelligent system with the rule-based system, although the proposed methodology exhibited minor errors in generating ROM diagrams for certain scenarios, the findings underscore the potential of the proposed model in mitigating the limitations of the rule-based system
Apology Components and Corporate Recovery: Understanding the Mechanisms Impacting Trust and Brand Equity
Get PDFApologies are crucial components of brand recovery after brand crises, yet the role of the apology components and apologizer's gender and status in shaping consumer responses remains understudied. This thesis aims to contribute to the existing literature on brand crises and apology effectiveness by investigating the impact of apology components (i.e., acknowledgment, remorse, compensation) and apology source (i.e., gender and status of the apologizer) on consumer recovery, with a focus on post-crisis trust and brand equity. Additionally, the study explores the mediating roles of perceived accountability, authenticity, and fairness in this relationship. The research involved an experiment with a 3 (apology component: acknowledgment, remorse, compensation) × 2 (gender of apologizer: male vs. female) × 2 (status of apologizer: CEO vs. employee) between-subject design where participants were exposed to a fictitious brand crisis news article and imagined themselves as affected consumers. Despite non-significant results, the study contributes theoretical insights into the complex interplay between apology components, source, and post-crisis outcomes. Trends in the data suggest potential relationships that warrant further exploration in future research
Ferrite with High Magnetization and Duplex Antenna System for Front-end Communication
Get PDFWireless and satellite communication systems demand a high data rate, which necessitates operating at Millimeter-wave bands. Thus, new efficient antennas and microwave devices are developed, which play an essential role in the design of an efficient front-end future communication system. Many challenges exist related to the present material properties and conventional
challenges related to fabrication. Most printed circuit board (PCB) based guiding systems suffer from high dielectric and radiation losses, support surface waves, and excite cavity modes. In addition, copper cladding surface roughness introduces losses and affects the substrate's equivalent
dielectric constant. Surface roughness would introduce invisible air gaps between two conducting surfaces creating a parallel plate (loosely referred to as PEC-PEC) waveguide supporting substantial signal leakage and losses due to the surface impedance. The newly developed printed gap waveguide technology would resolve such a problem by changing one of the plates with a magnetic conductor surface, thus, suppressing the leakage. This will be loosely referred to as PECPMC. As the magnetic conductor physically does not exist, an engineered artificial magnetic conductor (AMC) surface is realized by a periodic structure that has to be designed for the required
frequency band. The Dissertation aims to highlight some of these issues and solve some electromagnetic problems. In addition, a problem related to the limitation of the commercial ferrite materials that limit the bandwidth and possibly its application at mm-wave frequencies is tackled by building in-house new ferrite material capable of overcoming such problems. In-house disks of ferrite with high-magnetization made of nickel-zinc are presented in terms of their properties and application in the circulator design at mm-wave frequencies, which is considered a significant contribution of this Dissertation.
The dissertation comprises three parts. The first part presents a design of an integrated multilayer horn antenna providing wide bandwidth and high gain. For the first time, a solution is provided to control the leakages due to the surface roughness from imperfect copper cladding using the PECAMC
configuration of the horn radiator that is realized by a multilayer of PEC-AMC. In each layer of the horn, the opening is surrounded by periodic cells to suppress leakage and surface waves. In addition, the upper surface surrounding the horn's opening is covered by EBG mushroom cells to
act as a soft surface that suppresses the surface currents around the horn aperture and reduces edge diffraction, improving the radiation characteristics of the horn. The proposed horn antenna achieved 11 dBi gain and 20.5 % impedance bandwidth, with better than 26.5 dB co- to crosspolarization
in both E- and H-planes within 90∘. Most existing PCB-based circulators encounter massive dielectric losses, leading to spurious radiation and surface waves, degrading the system's overall performance. In the second part, this problem is resolved using printed gap waveguide technology that provides a packaged, low-loss, planar, cost-effective solution. The printed gap waveguide circulator provides 28.5% impedance bandwidth with better than 10 dB return loss and 12 dB isolation level throughout the operating frequency from 28.5-38 GHz. The first and second parts are integrated to form a full-duplex antenna system on the same layer with the proper
matching between their ports. These studies highlight the advantages of using the gap waveguide technology, which could be a step towards standardizing this technology. The final part of the work focuses on fabricating high-magnetization ferrite powder, which was
baked at a different temperature to verify the structural and magnetic properties. Later, the manufactured powder is pressed with a hydraulic machine to form a disk shape that can be used in the mm-wave spectrum. The microwave industry's highest available saturation magnetization is
around 5300 (G). In this work, different ferrite disks were fabricated with Nickel-zinc ferrite (NZF) composition utilizing different heat treatment atmospheres to heat the powders. The proposed technique provided a magnetization of 9500 (G), 1.8 times higher than the magnetization in
microwave and space industries. This will open a new doorway for the microwave and space industry supporting various future applications in the mm-wave spectrum. From the industrial point of view, only the standard ferrite diameter and thicknesses are available in the market, and a
custom-made disk requires much time and is expensive. A simple technique is described to fabricate the ferrite disk. Later, the same ferrite disk is deployed with a circulator operating in the mm-wave range with excellent measured isolation and return loss below -20 dB at the center frequency of 28 GHz
Cinematic Solidarities: Cinema Amidst Global Vistas of Struggle
No full textThe dissertation "Cinematic Solidarities: Cinema Amidst Global Vistas of Struggle" investigates how has cinema contributed to establishing transnational solidarities in the wake of the uprisings that traversed the globe throughout the 2010s. From the Arab World, across the Balkans, to Latin America, numerous participants in these struggles signaled the necessity of establishing alliances across national borders in order to confront formidable enemies—state oppression and racialized operations of capital. I trace how filmmakers, film festival organizers, programmers, and archival film researchers aligned their work and shaped their practice in response to the urgency of this political call. Three projects are at the center of this dissertation: the Subversive Film Festival, initiated in 2008 in Zagreb, Croatia, which through distinct programming strategy, focused on diverse traditions of political cinema, generated a meeting platform for regional and global leftists; "Luta ca caba inda," the project shaped around efforts to re-animate audio-visual materials from the Guinea-Bissau's Liberation War (1963-1974); and Subversive Film's still ongoing investigation and exhibition of the global reach of Palestinian Militant Cinema (1968-1982). By paying attention to the geography and movement of films and people in these projects, I explore how people behind them mobilized film cultural infrastructures at their hand toward creating new and reviving old solidarities. The transformative capacities of film cultural and filmmaking projects in these instances manifest themselves in two important ways. First, the projects established connections bringing together distant sites and various actors coming from different political and cultural backgrounds. Second, these projects not only changed the participant's perspectives and conceptions about the world. They were instrumental in the creation of new geopolitical imaginaries. In tracing and conceptualizing this transformative dimension of cinematic solidarities, the dissertation demonstrates cinema's potentiality to operate as a repository of tactics and strategies for myriad struggles to come
A Person-Centered Analysis of Help-Seeking Barriers and Facilitators in Emerging Adult Survivors of Sexual Violence
Get PDFSexual violence poses a serious threat to emerging adults’ development and mental health, but few seek help for their mental health. Guided by both developmental and socioecological models of service seeking, the purpose of the present study was to identify profiles of mental health help-seeking barriers (attitudinal, instrumental, and stigma-related) and facilitators (self-compassion) among emerging adult sexual violence survivors. A secondary purpose was to determine whether factors at multiple levels of the ecological system, including the university environment, were associated with profile membership. Undergraduate emerging adult survivors of childhood and past-year sexual violence (N = 286, 87.1% female), aged 18-29 (M = 21.83), completed measures of barriers to help-seeking, self-compassion, and socioecological covariates. Results of the latent profile analysis identified four profiles labeled according to how theoretically well-equipped they were to seek help based on observed patterns of barriers and self-compassion: Well-Equipped (36.71%), Under-Equipped (48.60%), Very Well-Equipped (9.44%), and Very Under-Equipped (5.25%). Findings suggest that over half of the sample was under-equipped to seek help, as evidenced by low levels of self-compassion and high levels of barriers. Greater campus cultural congruity was associated with a higher likelihood of membership in the Well-Equipped profile relative to the Under-Equipped profile. Implications for promoting help-seeking in this population are discussed