62 research outputs found
Realtime In-Network Cyberattack Detection in Power Grid Systems using a Programmable Network
Power grid communication networks are important systems to detect intrusions from an attacker due to them being necessary to maintain critical infrastructure. This thesis applies recent advancements in P4 technology to detect cyberattacks in SCADA systems. In previous work, a list has been compiled of potential attacks that exploit one of the most common protocols in SCADA systems, DNP3. Solutions for detecting these attacks can be categorized by the broad methods that they use. The two methods that are focused on are single-packet inspection and multiple-packet inspection. For each of these, a specific attack is chosen and a detection algorithm is developed. These attacks are the length overflow attack and the outstation write attack. The detection algorithm for these attacks can act as an example of the methods that they were chosen for. For one of these attacks, the outstation write attack, the effectiveness of the algorithm is evaluated. This is done in a simulated network using a network simulation tool called Mininet, and a virtual attack scenario is created. When the detection algorithm detects a malicious packet, it is simply dropped. This algorithm is compared to a simple forwarding program to determine its effectiveness in preventing the attacker’s desired effect on the network. The results show that the attack is effective at dropping malicious traffic in the network, making the attack unsuccessful
Realtime In-Network Cyberattack Detection in Power Grid Systems using a Programmable Network
Power grid communication networks are important systems to detect intrusions from an attacker due to them being necessary to maintain critical infrastructure. This thesis applies recent advancements in P4 technology to detect cyberattacks in SCADA systems. In previous work, a list has been compiled of potential attacks that exploit one of the most common protocols in SCADA systems, DNP3. Solutions for detecting these attacks can be categorized by the broad methods that they use. The two methods that are focused on are single-packet inspection and multiple-packet inspection. For each of these, a specific attack is chosen and a detection algorithm is developed. These attacks are the length overflow attack and the outstation write attack. The detection algorithm for these attacks can act as an example of the methods that they were chosen for. For one of these attacks, the outstation write attack, the effectiveness of the algorithm is evaluated. This is done in a simulated network using a network simulation tool called Mininet, and a virtual attack scenario is created. When the detection algorithm detects a malicious packet, it is simply dropped. This algorithm is compared to a simple forwarding program to determine its effectiveness in preventing the attacker’s desired effect on the network. The results show that the attack is effective at dropping malicious traffic in the network, making the attack unsuccessful
Doctor of Philosophy
dissertationAtomization is chaos. The breakup of liquid structures by a gas encompasses such a wide range of possible configurations that a definitive mechanism describing breakup in any and all situations is an impossibility. However, when focus is applied, trends can be teased out of experimental data that seem to appropriately describe the action undertaken. These studies sought to better understand atomization, specifically coaxial, two-stream, airblast (or air-assist) atomization in which a central liquid jet is broken up by an annular, high-velocity gas stream. The studies enclosed focused on identifying the effect of changing the atomizer's scale on atomization. While most (but not all) atomization studies only focus on the resulting far-field drop diameters, these studies placed the focus largely on the intermediate structures, in the form of the intact liquid jet (ILJ), while also quantifying the resulting drop diameters. The location and shape of the ILJ constantly change, and on its surface, wavelengths were seen to form and grow, which have been correlated to the resulting drop diameters in previous studies. The studies enclosed herein are unique in that they attempt to apply and explain exiting mechanism-based breakup mechanisms to regimes, fluids, and geometry changes not yet evaluated in the literature. Existing correlations were compared to the experimental data for a range of atomizer geometries, and when they were found lacking, Buckingham- theorem was used to develop new correlations for predicting behavior. Additionally, the method developed for the calculation of these parameters for other image sets is included, allowing for easy comparison and value verification. A small-scale, coaxial atomization system was used to atomize water and two silicone oils with air. The atomizers used in these studies had the same general geometry type, but had varying sizes, allowing for the effect of both scale and geometry to be evaluated. These studies quantified instability development and growth along with the resulting spray characteristics, allowing for correlations to be made between the two data sets as the more recent mechanism-based atomization models do. Existing mechanism-based models from the literature are compared to the experimental results, as these existing models have not been evaluated significantly with changing atomizer geometry, high-viscosity fluids, and high flow regimes as was done here. Additionally, two experimental campaigns were undertaken with atomizers used to operate the University of Utah's PDU-scale (process development unit) entrained flow gasifier. The first campaign showed the effect of gas velocity, atomizer load (total flow), and gas-liquid impingement angle on the qualitative cold-flow atomizer performance. These trends are then tied to behavior of the entrained flow gasifier, showing the existence of a minimum required degree of atomization to avoid substantial losses in fuel conversion and efficiency in a gasifier. The second campaign showed the effect of gas flow, liquid flow, and fluid on the quantitative cold-flow atomizer performance. While in the literature, changing fluid properties of Newtonian fluids are shown to have a relatively linear response on atomizer performance, the behavior of non-Newtonian fluids was shown to be much more complex and difficult to predict. The correlations developed for the small-scale atomizers are applied to the micro-hole atomizers and found to be erroneous for the change in atomizer geometry. Buckingham- theorem is then used to develop correlations to predict the spray Sauter mean diameter for the micro-hole atomizers. Slurry-fed combustion and gasification systems are but one industrial implementation of atomization. Atomization plays important roles in numerous other industries, and despite decades of study, it is not well understood. This document serves to shed some light on a few small, specific subsets of the topic
Quality of Life Occupational Therapy Measurement Tool for Patients with Lymphedema/Chronic Venous Edema
The objective of this project was the development of a tool in the form of a patient questionnaire to be used by Occupational Therapists (OT) treating patients with lymphedema/chronic venous edema. This questionnaire was designed to identify life factors beyond limb volume reduction and activity independence that correlate with the patients\u27 perceptions of an improved quality of life, therefore promoting Health Related Quality of Life (HRQoL).
Literature reviewed supported the premise that attainment of the typical OT goals of activity completion will not accomplish the desired result of lymphedema treatment, nor will lymphedema goal attainment of reduced limb measures achieve long-standing patient satisfaction. The Occupational Therapy Framework (AOTA, 2002) and the Ecological Model of Occupation (Dunn et al., 2003) constructs were applied to address patient specific factors to be included in the treatment planning for patients with edema/lymphedema.
A HRQoL measurement tool, called the Lymphedema/Chronic Venous Edema Patient Questionnaire, was developed to be used by lymphedema trained occupational therapists as an outcome measure of patient satisfaction after treatment. Further, through clinical use of this questionnaire, Health Related Quality of Life is more likely to be an intentional outcome of the occupational therapy lymphedema treatment process
Interview with Marsha Waind, OTR/L
This project, one of 29 life history interviews which are a part of a larger project, is titled Life Histories of Individuals Who Have Been Influential in Developing Occupational Therapy (OT) in North Dakota and Wyoming. The purpose of the project is to gather information about the history and evolution of occupational therapy (OT) practice in North Dakota and Wyoming through life histories of individuals who have been influential in developing OT in these two states. It is anticipated that the life history process will be a powerful way to gather this information. This study is intended to provide current and future generations of occupational therapists a view of the history and how occupational therapy practice has evolved from its inception to current practice in North Dakota and Wyoming.
The focus of this section was on Marsha Waind an occupational therapist practicing since 1975, with a majority of her career spent in Grand Forks, North Dakota. She was a graduate of the University of North Dakota Occupational Therapy Program in 1975. Marsha currently works for Altru Health System as the regional services manager. The interview with Marsha took place at her office in the Altru Hospital in Grand Forks, North Dakota. The interview was based on a qualitative research design with a focus on a life history approach. The Kawa Model helped to guide the development of some of the interview questions.
The semi-structured interview was guided by an interview schedule prepared by the project directors; the questions on the interview schedule were designed to be used with all the individuals as part of the larger project. The researchers were allowed to modify or add interview questions as needed for each specific interview
Exploring a fragile frontier of justice: A critical analysis of Martha Nussbaum's capabilities approach as a theory of children's rights
Contemporary discourse on children's rights is shaped by attempts to account for their full humanity. A core issue centers on the question of whether children's rights should take the cultivation of agency or the experience of vulnerability as their starting point. Martha Nussbaum employs her influential capabilities approach to argue that the cultivation of agency should be prioritized in children's rights if respect for their full humanity is to be demonstrated. This yields two key outcomes. First, Nussbaum's theory is shaped by an anthropology in which one's capacity to strive for self-determining agency in the face of worldly contingencies is a vital sign of his or her humanity. Second, Nussbaum's theory poses a challenge to the emphasis that the international human rights movement has consistently placed on the family since the adoption of the Universal Declaration of Human Rights in 1948. This dissertation argues that prioritizing agency over vulnerability in the manner Nussbaum's capabilities approach advocates will complicate the task of demonstrating respect for children's full humanity. The rights discourse that has unfolded over the last seven decades suggests that human flourishing at childhood is not easily disentangled from the relationship that exists between children and their parents (and biogenetic kin relations). Furthermore, Nussbaum has not critically engaged alternative models of children's rights, like Don Browning's integrationist theory, that take seriously the impact of familial connections in the early and important stages of development. Finally, Nussbaum's theory of social justice fails to satisfactorily account for either the fragility of human agency or the goodness of human vulnerability. Demonstrating respect for the full humanity of children means placing their concrete and particular experience of vulnerability at the center of discourse on their rights.Le discours moderne en matière de droits des enfants repose sur les tentatives de reconnaître la totalité de l'humanité qui les habite. Une question fondamentale consiste à définir si les droits de l'enfant devraient prendre racine dans le développement du soi et de ses potentialités d'action ou dans l'expérience de sa vulnérabilité. Martha Nussbaum se sert de son influente approche des capacités pour argumenter que l'épanouissement des capacités devrait être prioritaire au niveau des droits des enfants si le respect pour leur humanité entière doit être démontré. Cela comporte mène à deux principales issues. Premièrement, la théorie de Nussbaum prend racine dans l'anthropologie selon laquelle une personne qui est motivée par de l'autodétermination lorsqu'elle est confrontée à des imprévus de la vie courante constitue un signe immuable de son humanité. Deuxièmement, la théorie de Nussbaum représente un défi quand vient le temps de soutenir que le mouvement international en matière de droit de la personne repose constamment sur la famille, et ce, depuis l'adoption de la Déclaration universelle des droits de l'homme en 1948. Cette dissertation infirme que la priorisation de ressources intermédiaires aux dépens de la vulnérabilité comme le défend l'approche des capacités de Nussbaum compliquera une démonstration du respect de l'entière humanité des enfants. Le texte de droits qui a été élaboré au cours des sept dernières décennies porte à croire que l'épanouissement humain au moment de l'enfance se dissocie difficilement de la relation qui existe entre l'enfant et ses parents (y compris les relations parentales biogénétiques). De plus, Nussbaum n'a pas entrepris de démarche critique visant l'élaboration de modèles subsidiaires en matière de droits de l'enfant, comme la théorie intégrationniste de Don Browning, qui prend au sérieux l'impact des liens familiaux au cours des premiers stades du développement qui sont si importants. Enfin, la théorie de Nussbaum portant sur la justice sociale échoue au moment de reconnaître la fragilité des ressources humaines ou les bienfaits de la vulnérabilité humaine. Démontrer du respect envers l'entièreté de l'humanité des enfants signifie de placer une expérimentation concrète et particulière de la vulnérabilité au centre du discours portant sur leurs droits
- …