DC/DC converter 3D assembly for autonomous sensor nodes

This paper reports on the design and the manufacturing of an integrated DCDC converter, which respects the specificity of sensor node network: compactness, high efficiency in acquisition and transmission modes, and compatibility with miniature Lithium batteries. A novel integrated circuit (ASIC) has been designed and manufactured to provide regulated Voltage to the sensor node from miniaturized, thin film Lithium batteries. Then, a 3D integration technique has been used to integrate this ASIC in a 3 layers stack with high efficiency passives components, mixing the wafer level technologies from two different research institutions. Electrical results have demonstrated the feasibility of this integrated system and experiments have shown significant improvements in the case of oscillations in regulated voltage. However, stability of this output voltage toward the input voltage has still to be improved.

A simulation-based design method to transfer surface mount RF system to flip-chip die implementation

The flip-chip technology is a high chip density solution to meet the demand for very large scale integration design. For wireless sensor node or some similar RF applications, due to the growing requirements for the wearable and implantable implementations, flip-chip appears to be a leading technology to realize the integration and miniaturization. In this paper, flip-chip is considered as part of the whole system to affect the RF performance. A simulation based design is presented to transfer the surface mount PCB board to the flip-chip die package for the RF applications. Models are built by Q3D Extractor to extract the equivalent circuit based on the parasitic parameters of the interconnections, for both bare die and wire-bonding technologies. All the parameters and the PCB layout and stack-up are then modeled in the essential parts' design of the flip-chip RF circuit. By implementing simulation and optimization, a flip-chip package is re-designed by the parameters given by simulation sweep. Experimental results fit the simulation well for the comparison between pre-optimization and post-optimization of the bare die package's return loss performance. This design method could generally be used to transfer any surface mount PCB to flip-chip package for the RF systems or to predict the RF specifications of a RF system using the flip-chip technology.

Job retention and turnover: a study of child protection and welfare social workers in Ireland

Retaining social workers in child protection and welfare organisations has been identified as a problem in Ireland (McGrath, 2001; Ombudsman for Children, 2006; Houses of the Oireachtas, 2008) and internationally (Ellet et al., 2006; Mor Barak et al., 2006; Tham, 2006). While low levels of retention have been identified, there is no research that examines the factors in Ireland that influence the retention of social workers. In this thesis, data is analysed from qualitative interviews with 45 social workers in the Health Service Executive South about what influences their decisions to stay in or leave child protection and welfare social work. These social workers’ views are examined in relation to quantitative research on the levels of turnover and employment mobility of child protection and welfare social workers employed in the same organisation. Contrary to expectations, the study found that the retention rate of social workers during the period of data collection (March 2005 to December 2006) was high and that the majority of social workers remained positive about this work and their retention. The quality of social workers’ supervision, social supports from colleagues, high levels of autonomy, a commitment to child protection and welfare work, good variety in the work, and a perception that they were making a difference, emerged as important factors in social workers’ decisions to stay. Perceptions of being unsupported by the organisation, which was usually described in terms of high caseloads and demanding workloads, a lack of resources, work with involuntary clients and not being able to make a difference, were the most significant factors in social workers’ decisions to leave and/or to want to leave. Social workers felt particularly professionally unsupported when they received low quality and/or infrequent professional supervision. This thesis critiques the theories of perceived organisational support theory, social exchange theory and job characteristics theory, and uses the concept of ‘professional career’, to help analyse the retention of social workers in child protection and welfare.

Planning the deployment of fault-tolerant wireless sensor networks

Since Wireless Sensor Networks (WSNs) are subject to failures, fault-tolerance becomes an important requirement for many WSN applications. Fault-tolerance can be enabled in different areas of WSN design and operation, including the Medium Access Control (MAC) layer and the initial topology design. To be robust to failures, a MAC protocol must be able to adapt to traffic fluctuations and topology dynamics. We design ER-MAC that can switch from energy-efficient operation in normal monitoring to reliable and fast delivery for emergency monitoring, and vice versa. It also can prioritise high priority packets and guarantee fair packet deliveries from all sensor nodes. Topology design supports fault-tolerance by ensuring that there are alternative acceptable routes to data sinks when failures occur. We provide solutions for four topology planning problems: Additional Relay Placement (ARP), Additional Backup Placement (ABP), Multiple Sink Placement (MSP), and Multiple Sink and Relay Placement (MSRP). Our solutions use a local search technique based on Greedy Randomized Adaptive Search Procedures (GRASP). GRASP-ARP deploys relays for (k,l)-sink-connectivity, where each sensor node must have k vertex-disjoint paths of length ≤ l. To count how many disjoint paths a node has, we propose Counting-Paths. GRASP-ABP deploys fewer relays than GRASP-ARP by focusing only on the most important nodes – those whose failure has the worst effect. To identify such nodes, we define Length-constrained Connectivity and Rerouting Centrality (l-CRC). Greedy-MSP and GRASP-MSP place minimal cost sinks to ensure that each sensor node in the network is double-covered, i.e. has two length-bounded paths to two sinks. Greedy-MSRP and GRASP-MSRP deploy sinks and relays with minimal cost to make the network double-covered and non-critical, i.e. all sensor nodes must have length-bounded alternative paths to sinks when an arbitrary sensor node fails. We then evaluate the fault-tolerance of each topology in data gathering simulations using ER-MAC.

Deer forests, game shooting and landed estates in the South West of Ireland, 1840 - 1970

This thesis is concentrated on the historical aspects of the elitist field sports of deer stalking and game shooting, as practiced by four Irish landed ascendancy families in the south west of Ireland. Four great estates were selected for study. Two of these were, by Irish standards, very large: the Kenmare estate of over 136,000 acres in the ownership of the Roman Catholic Earls of Kenmare, and the Herbert estate of over 44,000 acres in the ownership of the Protestant Herbert family. The other two were, in relative terms, small: the Grehan estate of c.7,500 acres in the ownership of the Roman Catholic Grehan family, and the Godfrey estate of c.5,000 acres, in the ownership of the Protestant Barons Godfrey. This mixture of contrasting estate size, owner's religions, nobleman, minor aristocrat and untitled gentry should, it is argued, yield a diversity of the field sports and lifestyles of their owners, and go some way to assess the contributions, good or bad, they have bequeathed to modern Ireland. Equally, it should help in assessing what importance, if any, applied to hunting. In this context, hunting is here used in its broadest meaning, and includes deer stalking and game shooting, as well as hunting with dogs and hounds on foot and horseback. Where a specific type of hunting is involved, it is so described; for example, fox hunting, stag hunting, hare hunting. Similarly, the term game is sometimes used in sporting literature to encompass all species of quarry killed, and can include deer, ground game (hares and rabbits), waterfowl, and various species of game birds. Where it refers to specific species, these are so described; for example grouse, pheasants, woodcork, wild duck, etc. Since two of these estates - the Kenmare and Herbert - each created a deer forest, unique in mid-19th century Ireland, they form the core study estates; the two smaller estates serve as comparative studies. And, equally unique, as these two larger estates held the only remnant population of native Irish red deer, the survival of that herd itself forms a concomitant core area of analysis. The numerary descriptions applied to these animals in popular literature are critically reassessed against prime source historical evidence, as are the so-called deer forest 'clearances'. The core period, 1840 to 1970, is selected as the seminal period, spanning 130 years, from the creation of the deer forests to when a fundamental change in policy and administration was introduced by the state. Comparison is made with similar estates elsewhere, in Britain and especially in Scotland. Their influence on the Irish methods and style of hunting is historically examined.

Practice links [Issue 33, April 2009]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 33 features the Biennial child protection and welfare social work conference.

Practice Links [Issue 34, October 2009]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 34 includes notifications of Barnardos training sessions and details regarding a domestic violence research project.

Practice links [Issue 35, December, 2009]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 35 examines the work of Positive Behaviour Ireland and the new pre-school Curriculum framework; Aistear

Practice links [Issue 36, February 2010]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 36 features articles on equine assisted personal development, the National Child Care Information System and a report on Fieldwork Training for Social Workers

Practice links [Issue 38, June 2010]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 38 contains the text for a proposed constitutional amendment on children’s rights

Practice links [Issue 39, October 2010]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 39 contains information on the new Irish National Strategy on Domestic, Sexual and Gender–based Violence to be managed by COSC.

Practice links [Issue 40, December 2010]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 40 contains details of various international conferences and recently published research and resources designed to further professional development for social workers.

Practice links [Issue 41, February 2011]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 41 features a review of the research thesis which examines the effects of parental imprisonment upon children's behaviour.

Practice links [Issue 42, April 2011]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 42 features a report examining the measures undertaken by schools to reduce bulling and victimization.

Practice Links [Issue 45, December 2011]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 45 unveils a new, regular section in the publication entitled Practice Signposts. This section aims to promote quality research- informed databases.