Addressing non-linear hardware limitations and extending network coverage area for power aware wireless sensor networks

Science Foundation Ireland (07/CE/11147); Irish Research Council for Science Engineering and Technology (Embark Initiative)

The Ford administration, Angola and the perception of Post-Vietnam US credibility, 1974-1976

This thesis is a study of how the Gerald Ford administration struggled to address a perceived loss of US credibility after the collapse of Vietnam, with a focus on the role of Secretary of State Henry Kissinger in the formulation, implementation and subsequent defence of US Angolan policy. By examining the immediate post-Vietnam period, this thesis shows that Vietnam had a significant impact on Kissinger’s actions on Angola, which resulted in an ill conceived covert operation in another third world conflict. In 1974, Africa was a neglected region in Cold War US foreign policy, yet the effects of the Portuguese revolution led to a rapid decolonization of its African territories, of which Angola was to become the focus of superpower competition. After South Vietnam collapsed in April 1975, Kissinger became fixated on restoring the perceived loss of US prestige, Angola provided the first opportunity to address this. Despite objections from his advisors, Kissinger methodically engineered a covert program to assist two anti-Marxist guerrilla groups in Angola. As the crisis escalated, the media discovered the operation and the Congress decided to cease all funding. A period of heated tensions ensued, resulting in Kissinger creating a new African policy to outmanoeuvre his critics publicly, while privately castigating them to foreign leaders. This thesis argues that Kissinger’s dismissal of internal dissent and opposition from the Congress was influenced by what he perceived as bureaucrats being affected by the Vietnam syndrome, and his obsession with restoring US credibility. By looking at the private and public records – as expressed in government meetings and official reports, US newspaper and television coverage and diplomatic cables – this thesis addresses the question of how the lessons of Vietnam failed to influence Kissinger’s actions in Angola, but the lessons of Angola were heavily influential in the construction of a new US-African policy.

Health of the older worker in Ireland - occupational physical and psychosocial factors in the autumn of work life

Introduction: Worldwide, governments are striving to keep people in work to an older age. However, little is known about the effects of work on an older workforce. This thesis aims to investigate the importance of job characteristics to the antecedents and evolution of cardiovascular disease and functional limitations for the older worker (50+ years). Methods: Three studies were used in this thesis. The 5C (Cork Coronary Care Case- Control) Study investigated the association between job strain and a coronary event in males (n=208) 35-74 years old. The Mitchelstown Study examined the association between job characteristics and positive lifestyle behaviours and further, job characteristics and blood pressure for males and females 50-69 years (n=2,047). Finally, the Cork & Kerry Study investigated the physical effects of manual work and reported functional limitations/disabilities in a sample of 60-80 year olds (n=362). Results: Results from the 5C Study show a clear difference between younger (<50 years) and older (≥50 years) workers, with older workers who had a coronary event more likely to have high job strain and low job control. Data from the Mitchelstown Study showed workers with intermediate possibility for development or high quantitative demands (versus low) at work significantly more likely to have co-occurrence of positive lifestyle behaviours. Further, those who had high possibility for development were more likely to have high systolic blood pressure with no indication of recovery from this activation at night. Physically demanding work as reported by the participants of the Cork & Kerry Study was associated with functional limitations and activities of daily living disability for both the paid and unpaid worker. Discussion: The findings from this piece of work highlight the necessity to examine job characteristics and health outcomes in isolation for the over fifties. The challenge is to get this information into the workplace.

Has your work worked you too hard? Physically demanding work and disability in a sample of the older Irish population

There is a heightened need for the practitioner to be alert to the determinants of functional limitations and disabilities owing to the ageing workforce. This study investigated the association between work type and disability in older age in both the paid and the previously unexplored, unpaid worker (household labour).Data on demographic factors, physical measurements, work history and functional status were collected on three hundred and fifty seven 57-80-year-olds. Past or present work was identified as either physically demanding or not. Functional limitations and activities of daily living (ADL) disabilities were assessed using validated scales. Logistic regression was used to examine the relationship between the dependent variables and work type (physically demanding work or not physically demanding work).Over half of the sample reported doing physically demanding work. 20 % had complete function (n = 67), 65 % (n = 223) functional limitations and 15 % (n = 53) ADL disability. Physically demanding work was associated with functional limitations [OR 2.52 (1.41, 4.51), p = 0.01] and ADL disability [OR 2.10 (1.06, 4.17), p = 0.03] after adjustment for a measure of obesity and gender. When gender stratified, looking only at females, physically demanding work was associated with ADL disability [OR 2.79 (1.10, 7.07), p = 0.03] adjusted for a measure of obesity and household labour. Physically demanding work was related to functional limitations and ADL disability in older age. This is valuable information to inform practitioners in the treatment of older people with functional limitations and disabilities and in guiding interventions in the prevention of work related disability.

Subterfuge-safe trust management for delegation of permissions in open environments

Open environments involve distributed entities interacting with each other in an open manner. Many distributed entities are unknown to each other but need to collaborate and share resources in a secure fashion. Usually resource owners alone decide who is trusted to access their resources. Since resource owners in open environments do not have a complete picture of all trusted entities, trust management frameworks are used to ensure that only authorized entities will access requested resources. Every trust management system has limitations, and the limitations can be exploited by malicious entities. One vulnerability is due to the lack of globally unique interpretation for permission specifications. This limitation means that a malicious entity which receives a permission in one domain may misuse the permission in another domain via some deceptive but apparently authorized route; this malicious behaviour is called subterfuge. This thesis develops a secure approach, Subterfuge Safe Trust Management (SSTM), that prevents subterfuge by malicious entities. SSTM employs the Subterfuge Safe Authorization Language (SSAL) which uses the idea of a local permission with a globally unique interpretation (localPermission) to resolve the misinterpretation of permissions. We model and implement SSAL with an ontology-based approach, SSALO, which provides a generic representation for knowledge related to the SSAL-based security policy. SSALO enables integration of heterogeneous security policies which is useful for secure cooperation among principals in open environments where each principal may have a different security policy with different implementation. The other advantage of an ontology-based approach is the Open World Assumption, whereby reasoning over an existing security policy is easily extended to include further security policies that might be discovered in an open distributed environment. We add two extra SSAL rules to support dynamic coalition formation and secure cooperation among coalitions. Secure federation of cloud computing platforms and secure federation of XMPP servers are presented as case studies of SSTM. The results show that SSTM provides robust accountability for the use of permissions in federation. It is also shown that SSAL is a suitable policy language to express the subterfuge-safe policy statements due to its well-defined semantics, ease of use, and integrability.