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- Creators: Arizona State University
- Creators: Samuelson, Melissa
- Member of: Theses and Dissertations
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
- Status: Published
Description
Blockchain scalability is one of the issues that concerns its current adopters. The current popular blockchains have initially been designed with imperfections that in- troduce fundamental bottlenecks which limit their ability to have a higher throughput and a lower latency.
One of the major bottlenecks for existing blockchain technologies is fast block propagation. A faster block propagation enables a miner to reach a majority of the network within a time constraint and therefore leading to a lower orphan rate and better profitability. In order to attain a throughput that could compete with the current state of the art transaction processing, while also keeping the block intervals same as today, a 24.3 Gigabyte block will be required every 10 minutes with an average transaction size of 500 bytes, which translates to 48600000 transactions every 10 minutes or about 81000 transactions per second.
In order to synchronize such large blocks faster across the network while maintain- ing consensus by keeping the orphan rate below 50%, the thesis proposes to aggregate partial block data from multiple nodes using digital fountain codes. The advantages of using a fountain code is that all connected peers can send part of data in an encoded form. When the receiving peer has enough data, it then decodes the information to reconstruct the block. Along with them sending only part information, the data can be relayed over UDP, instead of TCP, improving upon the speed of propagation in the current blockchains. Fountain codes applied in this research are Raptor codes, which allow construction of infinite decoding symbols. The research, when applied to blockchains, increases success rate of block delivery on decode failures.
One of the major bottlenecks for existing blockchain technologies is fast block propagation. A faster block propagation enables a miner to reach a majority of the network within a time constraint and therefore leading to a lower orphan rate and better profitability. In order to attain a throughput that could compete with the current state of the art transaction processing, while also keeping the block intervals same as today, a 24.3 Gigabyte block will be required every 10 minutes with an average transaction size of 500 bytes, which translates to 48600000 transactions every 10 minutes or about 81000 transactions per second.
In order to synchronize such large blocks faster across the network while maintain- ing consensus by keeping the orphan rate below 50%, the thesis proposes to aggregate partial block data from multiple nodes using digital fountain codes. The advantages of using a fountain code is that all connected peers can send part of data in an encoded form. When the receiving peer has enough data, it then decodes the information to reconstruct the block. Along with them sending only part information, the data can be relayed over UDP, instead of TCP, improving upon the speed of propagation in the current blockchains. Fountain codes applied in this research are Raptor codes, which allow construction of infinite decoding symbols. The research, when applied to blockchains, increases success rate of block delivery on decode failures.
ContributorsChawla, Nakul (Author) / Boscovic, Dragan (Thesis advisor) / Candan, Kasim S (Thesis advisor) / Zhao, Ming (Committee member) / Arizona State University (Publisher)
Created2018
Description
Executive compensation is broken into two parts: one fixed and one variable. The fixed component of executive compensation is the annual salary and the variable components are performance-based incentives. Clawback provisions of executive compensation are designed to require executives to return performance-based, variable compensation that was erroneously awarded in the year of a misstatement. This research shows the need for the use of a new clawback provision that combines aspects of the two currently in regulation. In our current federal regulation, there are two clawback provisions in play: Section 304 of Sarbanes-Oxley and section 954 of The Dodd\u2014Frank Wall Street Reform and Consumer Protection Act. This paper argues for the use of an optimal clawback provision that combines aspects of both the current SOX provision and the Dodd-Frank provision, by integrating the principles of loss aversion and narcissism. These two factors are important to consider when designing a clawback provision, as it is generally accepted that average individuals are loss averse and executives are becoming increasingly narcissistic. Therefore, when attempting to mitigate the risk of a leader keeping erroneously awarded executive compensation, the decision making factors of narcissism and loss aversion must be taken into account. Additionally, this paper predicts how compensation structures will shift post-implementation. Through a survey analyzing the level of both loss- aversion and narcissism in respondents, the research question justifies the principle that people are loss averse and that a subset of the population show narcissistic tendencies. Both loss aversion and narcissism drove the results to suggest there are benefits to both clawback provisions and that a new provision that combines elements of both is most beneficial in mitigating the risk of executives receiving erroneously awarded compensation. I concluded the most optimal clawback provision is mandatory for all public companies (Dodd-Frank), targets all executives (Dodd-Frank), and requires the recuperation of the entire bonus, not just that which was in excess of what should have been received (SOX).
ContributorsLarscheid, Elizabeth (Author) / Samuelson, Melissa (Thesis director) / Casas-Arce, Pablo (Committee member) / WPC Graduate Programs (Contributor) / School of Accountancy (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
Blockchain is a sophisticated and complex technology that will have a massive impact on the public accounting industry. Currently there is concern surrounding how blockchain may impact the industry as a whole. Auditors and accountants are worried that this technology has the potential to replace the responsibilities they fulfill. However, blockchain technology will not replace accountants and will enhance their daily activities by eliminating menial tasks, providing increased transparency, and allowing time to be spent in areas that require more consideration. This will change the role of accountants and professionals, requiring them to be more technologically proficient and analytically minded. This paper is organized as follows. There will be an initial explanation of the technology to inform the reader of what blockchain is and how it works. Then there will be a discussion regarding how blockchain technology relates to, and can be utilized by, public accounting firms as well as the implications of blockchain on the public accounting industry. These implications will be discussed followed by why they are extraneous, and how to combat them in both the assurance and advisory practices. In conclusion, recommendations will be provided for public accounting firms on how to effectively utilize the technology to their benefit.
ContributorsLomsdalen, Stephen A (Co-author) / Charen, Stephanie (Co-author) / Samuelson, Melissa (Thesis director) / Garverick, Michael (Committee member) / School of Accountancy (Contributor) / WPC Graduate Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
Given its impact on the accounting profession and public corporations, Sarbanes-Oxley Act of 2002(SOX) is a widely researched regulation among accounting scholars. Research typically focuses on the impact it has had on corporations, executives and auditors, however, there is limited research that illustrates the impact SOX may have on average Americans. There were several US criminal code sections that resulted from the passing of SOX. Statute 1519, which is often referred to as the "anti-shredding provision", penalizes anyone who "knowingly alters, destroys, mutilates, conceals, covers up, falsifies, or makes a false entry in any record, document, or tangible object with the intent to" obstruct a current or foreseeable federal investigation. This statute, although intended to punish behavior similar to that which occurred in the early 2000s by corporations and auditors, has been used to charge people beyond its original intent. Several issues with the crafting of the statute cause its broad application and some litigation even reached the Supreme Court due to its vague wording. Not only is the statute being applied beyond the intent, there are other issues that legal scholars have critiqued it for. This statute is far from being the only law facing these issues as the same issues and critiques are found in the 14th amendment. Rewriting the statute seems to be the most effective way to address the concerns of judges, lawyers and defendants regarding the statute. In addition, Congress could have passed this statute outside of SOX to avoid being seen as overreaching if obstruction of justice related to documents was actually an issue outside of corporate fraud.
ContributorsGonzalez, Joana (Author) / Samuelson, Melissa (Thesis director) / Lowe, Jordan (Committee member) / School of Accountancy (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
The United States is arguably the most powerful country in the world boasting the largest GDP and yet there are over half a million homeless Americans as of November 2015. While traditional solutions to combat homelessness adequately assist the majority of people experiencing homelessness as a short-term issue, traditional solutions do not serve the complex needs of the chronically homeless. One creative solution being applied across the nation to end chronic homelessness is Housing First. This report assesses the feasibility of a Housing First program in Tucson Arizona to reduce unsheltered rates. It discusses the current state of homelessness across the nation and in Tucson, explains the existing methods used to reduce unsheltered rates and explores the cost and benefits of implementing such a program. This report concludes with recommendations for implementing a Housing First program in Tucson, Arizona.
ContributorsZamora, Emilia Faye (Author) / Samuelson, Melissa (Thesis director) / Lamoreaux, Phillip (Committee member) / Department of Supply Chain Management (Contributor) / School of Accountancy (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
This research is about urban homeless people's vulnerability to extreme temperatures and the related socio-spatial dynamics. Specifically, this research investigates heat related coping strategies homeless people use and how the urban environment setting impacts those coping strategies. Semi-structured interviews were conducted with homeless people in Phoenix, Arizona during the summer of 2010. The findings demonstrate that homeless people have a variety of coping strategies and the urban environment setting unjustly impacts those strategies. The results suggest a need for further studies that focus spatial environmental effects on homeless people and other vulnerable populations.
ContributorsSanchez, Cory (Author) / Johnson, John M. (Thesis advisor) / Harlan, Sharon L (Committee member) / Lauderdale, Pat (Committee member) / Arizona State University (Publisher)
Created2011
Description
Law enforcement officers are frequently tasked with addressing and responding to public safety and community concerns related to issues of homelessness. While interactions between law enforcement and individuals experiencing homelessness occur frequently, issues of homelessness also span public health, policy, and housing spheres. Because of this, several communities in the United States also lean on outreach workers to address issues of homelessness. Recent research has described both law enforcement officers and outreach workers as street-level bureaucrats. Both groups grapple with unique shift demands, lack of supervision, burnout, and issues such as turnover, all while leveraging their personal knowledge and connections to make decisions on a case-by- case basis.In two studies, this dissertation explores the role of the police and outreach workers in responses to issues of homelessness. This is important to address because there is evidence that these two groups have a high degree of contact with individuals experience homelessness and have similar decision-making processes. Yet, they are largely siloed from one another making it difficult to generate policies related to issues of homelessness that are informed by both groups. In study one, responses to close- and open-ended responses (N = 1,163) drawn from a survey distributed to law enforcement personnel are analyzed, merged, and interpreted. The second study of this dissertation is an ethnography of outreach workers in Maricopa County, Arizona. The collective findings from these two studies underscore a remarkable similarity between outreach worker and law enforcement decision making, as well as a growing need to strengthen the relationships between these two groups to support longer-term solutions. Co-created training guides and events can be constructed to enhance the relationship between these two groups and to support mutually beneficial outcomes.
Portions of this research were supported by a Law and Science Dissertation Grant, via the National Science Foundation, award SES-2016661 to Arizona State University. This project was also supported by Arizona State University’s Graduate College and Graduate Student and Professional Association’s Graduate Research Program Award. The findings and conclusions are those of the author and do not reflect the position of the National Science Foundation or Arizona State University.
ContributorsBrown, Katharine L (Author) / Telep, Cody W (Thesis advisor) / Lucio, Joanna (Committee member) / Young, Jacob Tn (Committee member) / Arizona State University (Publisher)
Created2023
Description
Smart cities are the next wave of rapid expansion of Internet of Things (IoT). A smart city is a designation given to a city that incorporates information and communication technologies (ICT) to enhance the quality and performance of urban services, such as energy, transportation, healthcare, communications, entertainments, education, e-commerce, businesses, city management, and utilities, to reduce resource consumption, wastage and overall costs. The overarching aim of a smart city is to enhance the quality of living for its residents and businesses, through technology. In a large ecosystem, like a smart city, many organizations and companies collaborate with the smart city government to improve the smart city. These entities may need to store and share critical data with each other. A smart city has several thousands of smart devices and sensors deployed across the city. Storing critical data in a secure and scalable manner is an important issue in a smart city. While current cloud-based services, like Splunk and ELK (Elasticsearch-Logstash-Kibana), offer a centralized view and control over the IT operations of these smart devices, it is still prone to insider attacks, data tampering, and rogue administrator problems. In this thesis, we present an approach using blockchain to recovering critical data from unauthorized modifications. We use extensive simulations based on complex adaptive system theory, for evaluation of our approach. Through mathematical proof we proved that the approach always detects an unauthorized modification of critical data.
ContributorsMishra, Vineeta (Author) / Yau, Sik-Sang (Thesis advisor) / Goul, Michael K (Committee member) / Huang, Dijiang (Committee member) / Arizona State University (Publisher)
Created2017
Description
Security requirements are at the heart of developing secure, invulnerable software. Without embedding security principles in the software development life cycle, the likelihood of producing insecure software increases, putting the consumers of that software at great risk. For large-scale software development, this problem is complicated as there may be hundreds or thousands of security requirements that need to be met, and it only worsens if the software development project is developed by a distributed development team. In this thesis, an approach is provided for software security requirement traceability for large-scale and complex software development projects being developed by distributed development teams. The approach utilizes blockchain technology to improve the automation of security requirement satisfaction and create a more transparent and trustworthy development environment for distributed development teams. The approach also introduces immutability, auditability, and non-repudiation into the security requirement traceability process. The approach is evaluated against existing software security requirement solutions.
ContributorsKulkarni, Adi Deepak (Author) / Yau, Stephen S. (Thesis advisor) / Banerjee, Ayan (Committee member) / Wang, Ruoyu (Committee member) / Baek, Jaejong (Committee member) / Arizona State University (Publisher)
Created2022
Description
The purpose of an election is for the voice of the voters to be heard. All the participants in an election must be able to trust that the result of an election is actually the opinion of the people, unaltered by anything or anyone that may be trying to sway the vote. In the voting process, any "black boxes" or secrets can lead to mistrust in the system. In this thesis, an approach is developed for an electronic voting framework that is transparent, auditable, and scalable, making it trustworthy and usable for a wide-scale election. Based on my analysis, linkable ring signatures are utilized in order to preserve voter privacy while ensuring that a corrupt authenticating authority could not sway the vote. A hierarchical blockchain framework is presented to make ring signatures a viable signature scheme even when working with large populations. The solution is evaluated for compliance with secure voting requirements and scalability.
ContributorsMarple, Sam (Author) / Yau, Sik-Sang (Thesis advisor) / Huang, Dijiang (Committee member) / Trieu, Ni (Committee member) / Arizona State University (Publisher)
Created2021