Malicious attacks on computer systems attempt to obtain and maintain illicit control over the victim system. To obtain unauthorized access, they often exploit vulnerabilities in the victim system, and to maintain illicit control, they apply various hiding techniques to remain stealthy. In this dissertation, we discuss and present solutions for two classes of security problems: TOCTTOU (time-of-check-to-time-of-use) and K-Queue. TOCTTOU is a vulnerability that can be exploited to obtain unauthorized root access, and K-Queue is a hiding technique that can be used to maintain stealthy control of the victim kernel. The first security problem is TOCTTOU, a race condition in Unix-style file systems in which an attacker exploits a small timing gap between a file system call that checks a condition and a use kernel call that depends on the condition. Our contributions on TOCTTOU include: (1) A model that enumerates the complete set of potential TOCTTOU vulnerabilities; (2) A set of tools that detect TOCTTOU vulnerabilities in Linux applications such as vi, gedit, and rpm; (3) A theoretical as well as an experimental evaluation of security risks that shows that TOCTTOU vulnerabilities can no longer be considered "low risk" given the wide-scale deployment of multiprocessors; (4) An event-driven protection mechanism and its implementation that defend Linux applications against TOCTTOU attacks at low performance overhead. The second security problem addressed in this dissertation is kernel queue or K-Queue, which can be used by the attacker to achieve continual malicious function execution without persistently changing either kernel code or data, which prevents state-of-the-art kernel integrity monitors such as CFI and SBCFI from detecting them. Based on our successful defense against a concrete instance of K-Queue-driven attacks that use the soft timer mechanism, we design and implement a solution to the general class of K-Queue-driven attacks, including (1) a unified static analysis framework and toolset that can generate specifications of legitimate K-Queue requests and the checker code in an automated way; (2) a runtime reference monitor that validates K-Queue invariants and guards such invariants against tampering; and (3) a comprehensive experimental evaluation of our static analysis framework and K-Queue Checkers.

<p>Healthcare is very information-intensive. Hence, it has become necessary to use the support of computers in order to efficiently improve such an information-intensive organisation.</p><p>This thesis points out deficiencies in the area of information security in home healthcare regarding personal integrity and secrecy. Home healthcare is, in Sweden, performed by the municipalities. The work is based on the recommendations and common advice for processing of personal data compiled by the Data Inspection Board. Two municipalities in the Västra Götaland Region have been investigated. One of the municipalities has a manual system and the other has a computerized system for personal data management.</p><p>The work includes a field study where persons from both municipalities have been observed. It also includes interviews based on the comprehensive questions from the Data Inspection Board and questions arisen from the observations.</p><p>The work shows that a very clear need of training among personnel involved in home healthcare. It also shows the need for elaborate security measures including levels on access profiles. A weak point concerning security is also the heavy use of facsimile transmission for information distribution.</p>

Hardwood bottomland ecosystems provide critical habitat for various wildlife among numerous ecosystem services. Since the 1800s, these forested wetlands have been logged and drained for agriculture. The federal government passed a series of legislative acts that protected wetlands and provided monetary support for restoration. The Wetlands Reserve Program (WRP) was established in 1990 with the goal of restoring ecological function in wetlands. Although several studies have measured plant and wildlife responses to WRP restorations, no standard protocol has been developed to monitor the state of ecological restoration at sites. Index of biotic integrity (IBI) models are commonly used to evaluate ecological function by assigning scores derived from biological characteristics measured at disturbed sites and comparing them with reference sites. Therefore, the objectives of my study were to: (1) characterize vegetation, amphibian and bird communities among 17 WRP restoration and 4 reference bottomland sites, and (2) develop IBI models for these communities to use in monitoring ecological restoration. My study was conducted across 10 counties in western Tennessee from March – August 2008, and communities were measured using standard sampling techniques. I detected 15 amphibian and 95 bird species at bottomland WRP sites, which ranged 2 – 21 years old. Anurans were common among sites, but salamanders were only detected at reference sites containing mature forests. The bird community changed predictably in response to succession, with grassland birds dominating young restoration sites and scrub-shrub and forest birds dominating older restoration and reference sites. Vegetation structure was related to site age, and a good predictor of bird community composition. Variables retained in the vegetation IBI model included density of snags, logs and overstory trees, basal area, and percent vertical cover measured using a profile board. The bird IBI model contained relative abundance of bark feeding, branch nesting, and twig nesting guilds. Presence of salamanders was the only variable in the amphibian IBI model. My results indicate that the WRP is contributing to the regional biodiversity of western Tennessee. The IBI models that I developed can be used for monitoring ecological restoration in Tennessee hardwood bottomlands; however, their applicability outside this region should be validated.

Recent interest in "greener" geothermal heating and cooling systems as well as developments in the quality assurance of cast-in-place concrete foundations has heightened the need for properly assessing thermal properties of soils. Therein, the ability of a soil to diffuse or absorb heat is dependent on the surrounding conditions (e.g. mineralogy, saturation, density, and insitu temperature). Prior to this work, the primary thermal properties (conductivity and heat capacity) had no correlation to commonly used soil exploration methods and therefore formed the focus of this thesis. Algorithms were developed in a spreadsheet platform that correlated input boring log information to thermal properties using known relationships between density, saturation, and thermal properties as well as more commonly used strength parameters from boring logs. Limited lab tests were conducted to become better acquainted with ASTM standards with the goal of proposing equipment for future development. Finally, sample thermal integrity profiles from cast-in-place foundations were used to demonstrate the usefulness of the developed algorithms. These examples highlighted both the strengths and weaknesses of present boring log data quality leaving room for and/or necessitating engineering judgment.

Pressure ulcers and related skin integrity threats are a significant problem in current transfer/transport systems used for spinal cord injury patients. To understand this problem twenty-three different slings with varying type, material, and features were analyzed in hopes to identify at-risk areas for skin integrity threats such as pressure ulcers. Population samples included non-disabled (otherwise referred to as "healthy") volunteers as well as SCI patients from the James A. Haley Veterans Hospital. High resolution pressure interface mapping was utilized to directly measure the interface pressures between the patient and sling interface. Overall results provide relevant feedback on the systems used and to suggest a particular type of sling that might reduce and possibly minimize skin integrity threats as well as extend safe patient handling guidelines with sling use. It was found that the highest interface pressures convened along the seams of the sling, regardless of manufacturer or type.

ABSTRACT Spirituality has been recognized as a positive factor in the lives of older adults, especially as it influences their emotional, mental, and physical well-being. This convenience sample study included 17 older adults residing at a faith based continuing care retirement community in Florida. The sample was represented by Caucasian older adults with an average age of 84 years, highly educated, majority Protestant and mostly female. Spiritual life reviews were conducted using spiritual life maps (Hodge, 2005) and semi-structured interview questions. Erikson's epigenetic stage of ego-integrity was used along with Butler's life review process and Tornstam's gerotranscendence as a conceptual framework for understanding late life development and spirituality in older adults. This mostly qualitative study used a hermeneutic phenomenological approach to analyze the responses to the open-ended interview questions about spirituality across the life-time. Ego-integrity was measured at the beginning and end of the spiritual life review study. Paired t-tests found that participation in the spiritual life review did not influence the ego integrity scores of participants. Specifically, there were no statistically significant difference between the pre ego integrity score (M=82.94, SD= 8.235) and the post ego integrity score (M=84.47, SD= 7.551); t (16) = -.769 p= .453. However, in comparison, the qualitative analysis revealed that the spiritual life review does influence ego-integrity in some participants. Additionally, the spiritual life review confirms gerotranscendence and contributes to information about spiritual development in the lives of older adults. The conclusion offers a discussion about the study's limitations, strengths, implications for future research, and suggestions for clinical practice.

published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy

This study evaluated the influence of academic, behavioral, and sociocultural variables on the implementation of Schoolwide Positive Behavior Support (SWPBS), a system intended to improve discipline in school buildings. The number of schools that are implementing SWPBS has been increasing dramatically over the years as school violence continues to rise and solutions are needed to improve school climate. This study examined the relationship between three categories of variables and the level of implementation of SWPBS in three multiple regression analyses. The categories were school demographic variables (i.e., ethnicity, socio-economic status, teacher: student ratio, percentage of teachers who are out-of-field), severity of need for change (suspensions, office referrals, percentage of students below grade level in reading), and team process variables (coaching, team functioning, administrative support). Of these variables, team functioning was the only one found to be sign ificantly related to implementation. A second component of the study involved collecting data relating to factors that were enablers or barriers to the implementation of SWPBS. Two-hundred and thirty-six school personnel completed a survey, Schoolwide Implementation Factor Survey (SWIF). The survey derived three factors through a factor analysis: school, staff, and students; principal; and assistant principal. These factors were all found to have a high Cronbach's alpha for internal consistency. There were significant differences between schools with a high, middle, and low level of implementation on all of these factors, with respondents from high implementing schools scoring the highest on all factors,and respondents from low implementing schools scoring the lowest. The item on the survey rated as the most helpful in the implementation process was "Expectations and rules that are clearly defined," while the item rated as the most problematic in the implementation process was "Adequat e funding for PBS." Overall, the results highlighted the complexity of implementing a system-wide change.(i.e., ethnicity, socio-economic status, teacher: student ratio, percentage of teachers who are out-of-field), severity of need for change (suspensions, office referrals, percentage of students below grade level in reading), and team process variables (coaching, team functioning, administrative support). Of these variables, team functioning was the only one found to be significantly related to implementation. A second component of the study involved collecting data relating to factors that were enablers or barriers to the implementation of SWPBS. Two-hundred and thirty-six school personnel completed a survey,Schoolwide Implementation Factor Survey (SWIF). The survey derived three factors through a factor analysis: school, staff, and students; principal; and assistant principal. These factors were all found to have a high Cronbach's alpha for internal consistency. There were signific ant differences between schools with a high, middle, and low level of implementation on all of these factors, with respondents from high implementing schools scoring the highest on all factors,and respondents from low implementing schools scoring the lowest. The item on the survey rated as the most helpful in the implementation process was "Expectations and rules that are clearly defined," while the item rated as the most problematic in the implementation process was "Adequate funding for PBS." Overall, the results highlighted the complexity of implementing a system-wide change.

Bakgrund: Över hela världen lever människor med HIV, en kronisk infektion som påverkar individens immunförsvar. Dessa människor har varit en utsatt grupp för diskriminering av samhället under flera år. Det vilar ett etiskt ansvar hos sjuksköterskan att bemöta och vårda människor på lika villkor samt med respekt för den personliga integriteten. Syfte: Syftet med litteraturstudien var att beskriva hur människor som lever med HIV upplever möten med vårdpersonal. Metod: Studien genomfördes som en allmän litteraturöversikt baserad på åtta kvalitativa vetenskapliga artiklar. Resultat: I resultatet framkom fyra huvudkategorier: Att bli dömd och diskriminerad, Känslan av att vara smittsam, Känna tillit eller misstro samt Att bli respekterad. Slutsats: Sjuksköterskan har möjligheter i mötet med människor som lever med HIV, att verka för att individens känslor av utanförskap samt inskränkande av den personliga integriteten reduceras. Då patientens unika erfarenheter och behov tas tillvara i mötet beskriver människor med HIV upplevelser av att bli sedd för den person de är. Vilket är av värde i omvårdnaden, då målet för sjuksköterskan är att stärka patientens hälsoprocesser och verka för en individanpassad vård. / Background: People are living with HIV all over the world, a chronic infection that affects the individual's immune system. These people have been a vulnerable group, discriminated by society for several years. There is an ethical responsibility of the nurse to respond to and nurture people on equal terms and with respect for the personal integrity. Aim: The aim of this study was to describe how people living with HIV experience the encounter with healthcare professionals. Method: The study was conducted as a general literature review based on eight qualitative scientific articles. Results: The results revealed four main categories Being judged and discriminated, Feelings of being contagious, An emotion of trust or distrust and Being respected. Conclusion: The nurse has opportunities in the meetings with people living with HIV, to ensure that the individuals’ feelings of alienation and restrictive of personal privacy are reduced. When the patients’ unique experiences and needs are utilized in the meeting, people with HIV describes that they are being seen for who they are. Which is in the value of nursing care where the aim of the nurse is to strengthen the patients’ health processes and promote individual care.

Porous tungsten is used to manufacture dispenser cathodes due to it refractory properties. Surface porosity is critical to functional performance of dispenser cathodes because it allows for an impregnated ceramic compound to migrate to the emitting surface, lowering its work function. Likewise, surface roughness is important because it is necessary to ensure uniform wetting of the molten impregnate during high temperature service. Current industry practice to achieve surface roughness and surface porosity requirements involves the use of a plastic infiltrant during machining. After machining, the infiltrant is baked and the cathode pellet is impregnated. In this context, cryogenic machining is investigated as a substitutionary process for the current plastic infiltration process. Along with significant reductions in cycle time and resource use, surface quality of cryogenically machined un-infiltrated (as-sintered) porous tungsten has been shown to significantly outperform dry machining. The present study is focused on examining the relationship between machining parameters and cooling condition on the as-machined surface integrity of porous tungsten. The effects of cryogenic pre-cooling, rake angle, cutting speed, depth of cut and feed are all taken into consideration with respect to machining-induced surface morphology. Cermet and Polycrystalline diamond (PCD) cutting tools are used to develop high performance cryogenic machining of porous tungsten. Dry and pre-heated machining were investigated as a means to allow for ductile mode machining, yet severe tool-wear and undesirable smearing limited the feasibility of these approaches. By using modified PCD cutting tools, high speed machining of porous tungsten at cutting speeds up to 400 m/min is achieved for the first time. Beyond a critical speed, brittle fracture and built-up edge are eliminated as the result of a brittle to ductile transition. A model of critical chip thickness (hc) effects based on cutting force, temperature and surface roughness data is developed and used to study the deformation mechanisms of porous tungsten under different machining conditions. It is found that when hmax = hc, ductile mode machining of otherwise highly brittle porous tungsten is possible. The value of hc is approximately the same as the average ligament size of the 80% density porous tungsten workpiece.