892 resultados para Three carrier ambiguity resolution, Phase bias calibration, Network adjustment
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The paper presents a detailed analysis on the collective dynamics and delayed state feedback control of a three-dimensional delayed small-world network. The trivial equilibrium of the model is first investigated, showing that the uncontrolled model exhibits complicated unbounded behavior. Then three control strategies, namely a position feedback control, a velocity feedback control, and a hybrid control combined velocity with acceleration feedback, are then introduced to stabilize this unstable system. It is shown in these three control schemes that only the hybrid control can easily stabilize the 3-D network system. And with properly chosen delay and gain in the delayed feedback path, the hybrid controlled model may have stable equilibrium, or periodic solutions resulting from the Hopf bifurcation, or complex stranger attractor from the period-doubling bifurcation. Moreover, the direction of Hopf bifurcation and stability of the bifurcation periodic solutions are analyzed. The results are further extended to any "d" dimensional network. It shows that to stabilize a "d" dimensional delayed small-world network, at least a "d – 1" order completed differential feedback is needed. This work provides a constructive suggestion for the high dimensional delayed systems.
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Despite the prominent use of the Suchey-Brooks (S-B) method of age estimation in forensic anthropological practice, it is subject to intrinsic limitations, with reports of differential inter-population error rates between geographical locations. This study assessed the accuracy of the S-B method to a contemporary adult population in Queensland, Australia and provides robust age parameters calibrated for our population. Three-dimensional surface reconstructions were generated from computed tomography scans of the pubic symphysis of male and female Caucasian individuals aged 15–70 years (n = 195) in Amira® and Rapidform®. Error was analyzed on the basis of bias, inaccuracy and percentage correct classification for left and right symphyseal surfaces. Application of transition analysis and Chi-square statistics demonstrated 63.9% and 69.7% correct age classification associated with the left symphyseal surface of Australian males and females, respectively, using the S-B method. Using Bayesian statistics, probability density distributions for each S-B phase were calculated, providing refined age parameters for our population. Mean inaccuracies of 6.77 (±2.76) and 8.28 (±4.41) years were reported for the left surfaces of males and females, respectively; with positive biases for younger individuals (<55 years) and negative biases in older individuals. Significant sexual dimorphism in the application of the S-B method was observed; and asymmetry in phase classification of the pubic symphysis was a frequent phenomenon. These results recommend that the S-B method should be applied with caution in medico-legal death investigations of Queensland skeletal remains and warrant further investigation of reliable age estimation techniques.
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In this article, we analyze the three-component reaction-diffusion system originally developed by Schenk et al. (PRL 78:3781–3784, 1997). The system consists of bistable activator-inhibitor equations with an additional inhibitor that diffuses more rapidly than the standard inhibitor (or recovery variable). It has been used by several authors as a prototype three-component system that generates rich pulse dynamics and interactions, and this richness is the main motivation for the analysis we present. We demonstrate the existence of stationary one-pulse and two-pulse solutions, and travelling one-pulse solutions, on the real line, and we determine the parameter regimes in which they exist. Also, for one-pulse solutions, we analyze various bifurcations, including the saddle-node bifurcation in which they are created, as well as the bifurcation from a stationary to a travelling pulse, which we show can be either subcritical or supercritical. For two-pulse solutions, we show that the third component is essential, since the reduced bistable two-component system does not support them. We also analyze the saddle-node bifurcation in which two-pulse solutions are created. The analytical method used to construct all of these pulse solutions is geometric singular perturbation theory, which allows us to show that these solutions lie in the transverse intersections of invariant manifolds in the phase space of the associated six-dimensional travelling wave system. Finally, as we illustrate with numerical simulations, these solutions form the backbone of the rich pulse dynamics this system exhibits, including pulse replication, pulse annihilation, breathing pulses, and pulse scattering, among others.
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Flood related scientific and community-based data are rarely systematically collected and analysed in the Philippines. Over the last decades the Pagsangaan River Basin, Leyte, has experienced several flood events. However, documentation describing flood characteristics such as extent, duration or height of these floods are close to non-existing. To address this issue, computerized flood modelling was used to reproduce past events where there was data available for at least partial calibration and validation. The model was also used to provide scenario-based predictions based on A1B climate change assumptions for the area. The most important input for flood modelling is a Digital Elevation Model (DEM) of the river basin. No accurate topographic maps or Light Detection And Ranging (LIDAR)-generated data are available for the Pagsangaan River. Therefore, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Map (GDEM), Version 1, was chosen as the DEM. Although the horizontal spatial resolution of 30 m is rather desirable, it contains substantial vertical errors. These were identified, different correction methods were tested and the resulting DEM was used for flood modelling. The above mentioned data were combined with cross-sections at various strategic locations of the river network, meteorological records, river water level, and current velocity to develop the 1D-2D flood model. SOBEK was used as modelling software to create different rainfall scenarios, including historic flooding events. Due to the lack of scientific data for the verification of the model quality, interviews with local stakeholders served as the gauge to judge the quality of the generated flood maps. According to interviewees, the model reflects reality more accurately than previously available flood maps. The resulting flood maps are now used by the operations centre of a local flood early warning system for warnings and evacuation alerts. Furthermore these maps can serve as a basis to identify flood hazard areas for spatial land use planning purposes.
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The assembly of retroviruses such as HIV-1 is driven by oligomerization of their major structural protein, Gag. Gag is a multidomain polyprotein including three conserved folded domains: MA (matrix), CA (capsid) and NC (nucleocapsid)(1). Assembly of an infectious virion proceeds in two stages(2). In the first stage, Gag oligomerization into a hexameric protein lattice leads to the formation of an incomplete, roughly spherical protein shell that buds through the plasma membrane of the infected cell to release an enveloped immature virus particle. In the second stage, cleavage of Gag by the viral protease leads to rearrangement of the particle interior, converting the non-infectious immature virus particle into a mature infectious virion. The immature Gag shell acts as the pivotal intermediate in assembly and is a potential target for anti-retroviral drugs both in inhibiting virus assembly and in disrupting virus maturation(3). However, detailed structural information on the immature Gag shell has not previously been available. For this reason it is unclear what protein conformations and interfaces mediate the interactions between domains and therefore the assembly of retrovirus particles, and what structural transitions are associated with retrovirus maturation. Here we solve the structure of the immature retroviral Gag shell from Mason-Pfizer monkey virus by combining cryo-electron microscopy and tomography. The 8-angstrom resolution structure permits the derivation of a pseudo-atomic model of CA in the immature retrovirus, which defines the protein interfaces mediating retrovirus assembly. We show that transition of an immature retrovirus into its mature infectious form involves marked rotations and translations of CA domains, that the roles of the amino-terminal and carboxy-terminal domains of CA in assembling the immature and mature hexameric lattices are exchanged, and that the CA interactions that stabilize the immature and mature viruses are almost completely distinct.
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Organizations from every industry sector seek to enhance their business performance and competitiveness through the deployment of contemporary information systems (IS), such as Enterprise Systems (ERP). Investments in ERP are complex and costly, attracting scrutiny and pressure to justify their cost. Thus, IS researchers highlight the need for systematic evaluation of information system success, or impact, which has resulted in the introduction of varied models for evaluating information systems. One of these systematic measurement approaches is the IS-Impact Model introduced by a team of researchers at Queensland University of technology (QUT) (Gable, Sedera, & Chan, 2008). The IS-Impact Model is conceptualized as a formative, multidimensional index that consists of four dimensions. Gable et al. (2008) define IS-Impact as "a measure at a point in time, of the stream of net benefits from the IS, to date and anticipated, as perceived by all key-user-groups" (p.381). The IT Evaluation Research Program (ITE-Program) at QUT has grown the IS-Impact Research Track with the central goal of conducting further studies to enhance and extend the IS-Impact Model. The overall goal of the IS-Impact research track at QUT is "to develop the most widely employed model for benchmarking information systems in organizations for the joint benefit of both research and practice" (Gable, 2009). In order to achieve that, the IS-Impact research track advocates programmatic research having the principles of tenacity, holism, and generalizability through extension research strategies. This study was conducted within the IS-Impact Research Track, to further generalize the IS-Impact Model by extending it to the Saudi Arabian context. According to Hofsted (2012), the national culture of Saudi Arabia is significantly different from the Australian national culture making the Saudi Arabian culture an interesting context for testing the external validity of the IS-Impact Model. The study re-visits the IS-Impact Model from the ground up. Rather than assume the existing instrument is valid in the new context, or simply assess its validity through quantitative data collection, the study takes a qualitative, inductive approach to re-assessing the necessity and completeness of existing dimensions and measures. This is done in two phases: Exploratory Phase and Confirmatory Phase. The exploratory phase addresses the first research question of the study "Is the IS-Impact Model complete and able to capture the impact of information systems in Saudi Arabian Organization?". The content analysis, used to analyze the Identification Survey data, indicated that 2 of the 37 measures of the IS-Impact Model are not applicable for the Saudi Arabian Context. Moreover, no new measures or dimensions were identified, evidencing the completeness and content validity of the IS-Impact Model. In addition, the Identification Survey data suggested several concepts related to IS-Impact, the most prominent of which was "Computer Network Quality" (CNQ). The literature supported the existence of a theoretical link between IS-Impact and CNQ (CNQ is viewed as an antecedent of IS-Impact). With the primary goal of validating the IS-Impact model within its extended nomological network, CNQ was introduced to the research model. The Confirmatory Phase addresses the second research question of the study "Is the Extended IS-Impact Model Valid as a Hierarchical Multidimensional Formative Measurement Model?". The objective of the Confirmatory Phase was to test the validity of IS-Impact Model and CNQ Model. To achieve that, IS-Impact, CNQ, and IS-Satisfaction were operationalized in a survey instrument, and then the research model was assessed by employing the Partial Least Squares (PLS) approach. The CNQ model was validated as a formative model. Similarly, the IS-Impact Model was validated as a hierarchical multidimensional formative construct. However, the analysis indicated that one of the IS-Impact Model indicators was insignificant and can be removed from the model. Thus, the resulting Extended IS-Impact Model consists of 4 dimensions and 34 measures. Finally, the structural model was also assessed against two aspects: explanatory and predictive power. The analysis revealed that the path coefficient between CNQ and IS-Impact is significant with t-value= (4.826) and relatively strong with â = (0.426) with CNQ explaining 18% of the variance in IS-Impact. These results supported the hypothesis that CNQ is antecedent of IS-Impact. The study demonstrates that the quality of Computer Network affects the quality of the Enterprise System (ERP) and consequently the impacts of the system. Therefore, practitioners should pay attention to the Computer Network quality. Similarly, the path coefficient between IS-Impact and IS-Satisfaction was significant t-value = (17.79) and strong â = (0.744), with IS-Impact alone explaining 55% of the variance in Satisfaction, consistent with results of the original IS-Impact study (Gable et al., 2008). The research contributions include: (a) supporting the completeness and validity of IS-Impact Model as a Hierarchical Multi-dimensional Formative Measurement Model in the Saudi Arabian context, (b) operationalizing Computer Network Quality as conceptualized in the ITU-T Recommendation E.800 (ITU-T, 1993), (c) validating CNQ as a formative measurement model and as an antecedent of IS Impact, and (d) conceptualizing and validating IS-Satisfaction as a reflective measurement model and as an immediate consequence of IS Impact. The CNQ model provides a framework to perceptually measure Computer Network Quality from multiple perspectives. The CNQ model features an easy-to-understand, easy-to-use, and economical survey instrument.
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Video-based training combined with flotation tank recovery may provide an additional stimulus for improving shooting in basketball. A pre-post controlled trial was conducted to assess the effectiveness of a 3 wk intervention combining video-based training and flotation tank recovery on three-point shooting performance in elite female basketball players. Players were assigned to an experimental (n=10) and control group (n=9). A 3 wk intervention consisted of 2 x 30 min float sessions a week which included 10 min of video-based training footage, followed by a 3 wk retention phase. A total of 100 three-point shots were taken from 5 designated positions on the court at each week to assess three-point shooting performance. There was no clear difference in the mean change in the number of successful three-point shots between the groups (-3%; ±18%, mean; ±90% confidence limits). Video-based training combined with flotation recovery had little effect on three-point shooting performance.
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A composite paraffin-based phase change material (PCM) was prepared by blending composite paraffin and calcined diatomite through the fusion adsorption method. In this study, raw diatomite was purified by thermal treatment in order to improve the adsorption capacity of diatomite, which acted as a carrier material to prepare shape-stabilized PCMs. Two forms of paraffin (paraffin waxes and liquid paraffin) with different melting points were blended together by the fusion method, and the optimum mixed proportion with a suitable phase-transition temperature was obtained through differential scanning calorimetry (DSC) analysis. Then the prepared composite paraffin was adsorbed in calcined diatomite. The prepared paraffin/calcined diatomite composites were characterized by the scanning electron microscope (SEM) and Fourier transformation infrared (FT-IR) analysis techniques. Thermal energy storage properties of the composite PCMs were determined by DSC method. DSC results showed that there was an optimum adsorption ratio between composite paraffin and calcined diatomite and the phase-transition temperature and the latent heat of the composite PCMs were 33.04 ◦C and 89.54 J/g, respectively. Thermal cycling test of composite PCMs showed that the prepared material is thermally reliable and chemically stable. The obtained paraffin/calcined diatomite composites have proper latent heat and melting temperatures, and show practical significance and good potential application value.
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Modelling how a word is activated in human memory is an important requirement for determining the probability of recall of a word in an extra-list cueing experiment. Previous research assumed a quantum-like model in which the semantic network was modelled as entangled qubits, however the level of activation was clearly being over-estimated. This paper explores three variations of this model, each of which are distinguished by a scaling factor designed to compensate the overestimation.
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A hydrogen gas sensor based on Pt/nanostructured ZnO Schottky diode has been developed. Our proposed theoretical model allows for the explanation of superior dynamic performance of the reverse biased diode when compared to the forward bias operation. The sensor was evaluated with low concentration H2 gas exposures over a temperature range of 280°C to 430°C. Upon exposure to H2 gas, the effective change in free carrier concentration at the Pt/structured ZnO interface is amplified by an enhancement factor, effectively lowering the reverse barrier, producing a large voltage shift. The lowering of the reverse barrier permits a faster response in reverse bias operation, than in forward bias operation.
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Growing community concerns about the ecological, social, cultural and economic impact of housing and urban projects poses new challenges for those who have to deliver them. It is important that these concerns are addressed as part of the community engagement processes on projects. Community engagement is traditionally perceived as the purview of planners and disconnected from the building construction process. This is despite most project approval processes mandating on-going community engagement over the project’s entire lifetime. There is evidence that point to a culture of ambiguity and ambivalence among building professionals about their roles, responsibilities and expectations of community engagement during the construction phase of projects. This has contributed to a culture of distrust between communities and the construction industry. There is a clear need to build capacity among building professionals to empower them as active participants in community engagement processes which can promote better project outcomes and minimise delays and conflicts. This paper describes a process that utilises the Theory of Planned Behaviour as a framework to equip building professionals with the skills they need to engage effectively with local communities during the construction phase of projects.
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Introduction: Participants may respond to phases of a workplace walking program at different rates. This study evaluated the factors that contribute to the number of steps through phases of the program. The intervention was automated through a web-based program designed to increase workday walking. Methods: The study reviewed independent variable influences throughout phases I–III. A convenience sample of university workers (n=56; 43.6±1.7 years; BMI 27.44±.2.15 kg/m2; 48 female) were recruited at worksites in Australia. These workers were given a pedometer (Yamax SW 200) and access to the website program. For analyses, step counts entered by workers into the website were downloaded and mean workday steps were compared using a seemingly unrelated regression. This model was employed to capture the contemporaneous correlation within individuals in the study across observed time periods. Results: The model predicts that the 36 subjects with complete information took an average 7460 steps in the baseline two week period. After phase I, statistically significance increases in steps (from baseline) were explained by age, working status (full or part time), occupation (academic or professional), and self reported public transport (PT) use (marginally significant). Full time workers walked more than part time workers by about 440 steps, professionals walked about 300 steps more than academics, and PT users walked about 400 steps more than non-PT users. The ability to differentiate steps after two weeks among participants suggests a differential affect of the program after only two weeks. On average participants increased steps from week two to four by about 525 steps, but regular auto users had nearly 750 steps less than non-auto users at week four. The effect of age was diminished in the 4th week of observation and accounted for 34 steps per year of age. In phase III, discriminating between participants became more difficult, with only age effects differentiating their increase over baseline. The marginal effect of age by phase III compared to phase I, increased from 36 to 50, suggesting a 14 step per year increase from the 2nd to 6th week. Discussion: The findings suggest that participants responded to the program at different rates, with uniformity of effect achieved by the 6th week. Participants increased steps, however a tapering off occurred over time. Age played the most consistent role in predicting steps over the program. PT use was associated with increased step counts, while Auto use was associated with decreased step counts.
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This thesis explores how governance networks prioritise and engage with their stakeholders, by studying three exemplars of “Regional Road Group” governance networks in Queensland, Australia. In the context of managing regionally significant road works programs, stakeholder prioritisation is a complex activity which is unlikely to influence interactions with stakeholders outside of the network. However, stakeholder priority is more likely to influence stakeholder interactions within the networks themselves. Both stakeholder prioritisation and engagement are strongly influenced by the way that the networks are managed, and in particular network operating rules and continuing access to resources.
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The electron Volt Spectrometer (eVS) is an inverse geometry filter difference spectrometer that has been optimised to measure the single atom properties of condensed matter systems using a technique known as Neutron Compton Scattering (NCS) or Deep Inelastic Neutron Scattering (DINS). The spectrometer utilises the high flux of epithermal neutrons that are produced by the ISIS neutron spallation source enabling the direct measurement of atomic momentum distributions and ground state kinetic energies. In this paper the procedure that is used to calibrate the spectrometer is described. This includes details of the method used to determine detector positions and neutron flight path lengths as well as the determination of the instrument resolution. Examples of measurements on 3 different samples are shown, ZrH2, 4He and Sn which show the self-consistency of the calibration procedure.
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Alcohol consumption is enmeshed with Australian culture (Palk, 2008) and the use and misuse of alcohol contributes to considerable health and social harms (Barbor et al., 2010; English et al., 1995; Gutjahr, Gmel, & Rehm, 2001; Palk, 2008; Steenkamp, Harrison, & Allsop, 2002). Despite shifts in the way that alcohol is consumed and how it is used, it has been reported that one-third of all alcohol consumed is done so within licensed premises (Lang, Stockwell, Rydon, & Gamble, 1992). Consequently, licensed premises are over-represented as settings in which alcohol-related harms occur. These harms, particularly those related to violence, are associated with particular licensed premises operating in the night-time economy (Briscoe & Donnelly, 2001b; Chikritzhs, Stockwell, & Masters, 1997; Homel, Tomsen, & Thommeny, 1991; Stockwell, 1997). Police have a role in not only responding to the manifestation of harms, such as crime, injuries, assaults, domestic violence, stealing and sexual offences, but they also have a role in preventing problems, and thereby reducing alcohol and other drug-related harms (Doherty & Roche, 2003). Given the extent of alcohol consumption within licensed premises and the nature and extent of the harms, as well as the lack of opportunity to influence outcomes in other settings (e.g. the home), licensed premises offer police and other stakeholders a significant opportunity to influence positively the reduction of alcoholrelated harm. This research focuses specifically on the police role in policing licensed premises. Primarily, this research aims to investigate the factors which are relevant to why and how police officers respond to alcohol-related incidents inside and outside licensed premises. It examines the attitudes and beliefs of police and assesses their knowledge, capacity and ability to effectively police licensed premises. The research methodology uses three distinct surveys. Each contributes to understanding the motivations and practice of police officers in this important area of harm reduction. Study One involved a survey of police officers within a police district (Brisbane Central District) in Queensland, Australia and used a comprehensive questionnaire involving both quantitative and qualitative techniques. A key research outcome of Study One was the finding that officers had low levels of knowledge of the strategies that are effective in addressing alcohol-related harm both inside and outside licensed premises. Paradoxically, these officers also reported extensive recent experience in dealing with alcohol issues in these locations. In addition, these officers reported that alcohol was a significant contextual factor in the majority of matters to which they responded. Officers surveyed reported that alcohol increased the difficulty of responding to situations and that licensed premises (e.g. nightclubs, licensed clubs and hotels) were the most difficult contexts to police. Those surveyed were asked to self-assess their knowledge of the Liquor Act (Qld), which is the primary legislative authority in Queensland for regulating licensed premises. Surprisingly, well over half of the officers (65%) reported ‘no’ to ‘fair’ knowledge of the Act, despite officers believing that their skill level to police such premises was in the ‘good to very good range’. In an important finding, officers reported greater skill level to police outside licensed premises than inside such premises, indicating that officers felt less capable, from a skill perspective, to operate within the confines of a licensed premise than in the environment immediately outside such premises. Another key finding was that officers reported greater levels of training in responding to situations outside and around licensed premises than to situations inside licensed premises. Officers were also asked to identify the frequency with which they employed specified regulatory enforcement and community-based strategies. Irrespective of the type of response, ‘taking no action’ or passive policing interventions were not favoured by officers. The findings identified that officers favoured taking a range of strategies (sending home, releasing into the custody of friends, etc.) in preference to arrest. In another key finding, officers generally reported their support for operational stakeholder partnership approaches to policing licensed premises. This was evidenced by the high number of officers (over 90%) reporting that there should be shared responsibility for enforcing the provisions of the Liquor Act. Importantly, those surveyed also identified the factors which constrain or prevent them from policing licensed premises. Study Two involved interviewing a small but comprehensive group (n=11) of senior managers from within the Queensland Police Service (QPS) who have responsibility for setting operational and strategic policy. The aim of this study was to examine the attitudes, perceptions and influence that senior officers (at the strategy and policy-setting level) had on the officers at the operational level. This qualitative study was carried out using a purposive sampling (Denzin & Lincoln, 2005; Guba & Lincoln, 1989), focused interview and thematic analytic approach. The interview participants were drawn from three tiers of management at district, regional as well as the whole-of-organisational level. The first key theme emerging from the study related to role, in terms of both the QPS broader organisational role, and the individual officer role with respect to the policing of licensed premises. For the QPS organisational role, participants at all three strategic levels had a high degree of congruity as to the organisations service role; that is, to enhance public safety. With respect to participants’ beliefs as to whether police officers have knowledge and understanding of their individual roles concerning licensed premises (as opposed to the QPS role), participants reported most commonly that officers had a reasonable to clear understanding of their role. Participant comments also were supportive of the view that officers operating in the research area, Brisbane Central District (BCD), had a clearer understanding of their role than police operating in other locations. The second key theme to emerge identified a disparity between the knowledge and capability of specialist police, compared with general duties police, to police licensed premises. In fact, a number of the responses to a variety of questions differentiated specialist and general police in a range of domains. One such example related to the clarity of understanding of officer role. Participants agreed that specialist police (Liquor Enforcement & Proactive Strategies [LEAPS] officers) had more clarity of understanding in terms of their role than generalist police. Participants also were strongly of the opinion that specialist police had higher skill levels to deal with issues both inside and outside licensed premises. Some participants expressed the view that general duty police undertook purely response-related activities, or alternatively, dealt with lower order matters. Conversely, it was viewed that specialist police undertook more complex tasks because of their higher levels of knowledge and skill. The third key theme to emerge concerned the identification of barriers that serve to restrict or prevent police officers from policing licensed premises. Participant responses strongly indicated that there was a diversity of resourcing barriers that restrict police from undertaking their roles in licensed premises. Examples of such barriers were the lack of police and the low ratio of police to patrons, available officer time, and lack of organisational investment in skills and knowledge acquisition. However, some participants indicated that police resourcing in the BCD was appropriate and officers were equipped with sufficient powers (policy and legislation). Again, the issue of specialist police was raised by one participant who argued that increasing the numbers of specialist police would ameliorate the difficulties for police officers policing licensed premises. The fourth and last key theme to emerge from Study Two related to the perception of senior officers regarding the opportunity and capability of officers to leverage off external partnerships to reduce harms inside and outside licensed premises. Police working in partnership in BCD was seen as an effective harm reduction strategy and strongly supported by the participants. All participants demonstrated a high degree of knowledge as to who these partners were and could identify those government, non-government and community groups precisely. Furthermore, the majority of participants also held strong views that the partnerships were reasonably effective and worked to varying degrees depending on the nature of the partnership and issues such as resourcing. These senior officers identified better communication and coordination as factors that could potentially strengthen these partnerships. This research finding is particularly important for senior officers who have the capacity to shape the policy and strategic direction of the police service, not only in Queensland but throughout Australasia. Study Three examined the perceptions of those with links to the broader liquor industry (government, non-government and community but exclusive of police) concerning their understanding of the police role and the capacity of police to reduce alcohol-related harm inside and outside licensed premises, and their attitudes towards police. Participants (n=26) surveyed represented a range of areas including the liquor industry, business represenatives and government representatives from Queensland Fire and Rescue Service, Queensland Ambulance Service, Brisbane City Council and Queensland Health. The first key theme to emerge from Study Three related to participant understanding of the QPS organisational role, and importantly, individual officer role in policing licensed premises. In terms of participant understanding of the QPS role there was a clear understanding by the majority of participants that the police role was to act in ways consistent with the law and to otherwise engage in a range of enforcement-related activities. Participants saw such activities falling into two categories. The first category related to reactive policing, which included actions around responding to trouble in licensed premises, monitoring crowd controllers and removing trouble-makers. In the second category, proactive approaches, participants identified the following activities as consistent with that approach: early intervention with offenders, support of licensed premises operators and high visibility policing. When participants were asked about their understanding of individual officer roles in the policing of licensed premises, a range of responses were received but the consistent message that emerged was that there is a different role to be played by general duty (uniformed) police compared to specialist (LEAPS Unit) police, which reflects differences in knowledge, skill and capability. The second key theme that emerged from the data related to the external participants’ views of the knowledge and capability of specialist police, compared with general duty police, to police licensed premises. As noted in the first key theme, participants were universally of the view that the knowledge, skill and capability of police in specialist units (LEAPS Unit) was at a higher level than that of general duty police. Participants observed that these specialist officers were better trained than their colleagues in generalist areas and were therefore better able to intervene knowledgeably and authoritatively to deal with problems and issues as they emerged. Participants also reported that officers working within BCD generally had a positive attitude to their duties and had important local knowledge that they could use in the resolution of alcohol-related issues. Participants also commented on the importance of sound and effective QPS leadership, as well as the quality of the leadership in BCD. On both these measures, there was general consensus from participants, who reported positively on the importance and effectiveness of such leadership in BCD. The third key theme to emerge from Study Three concerned the identification of barriers that serve to restrict or prevent police officers from policing licensed premises. Overwhelmingly, external participants reported the lack of human resources (i.e. police officers) as the key barrier. Other resourcing limitations, such as available officer time, police computer systems, and the time taken to charge offenders, were identified as barriers. Some participants identified barriers in the liquor industry such as ‘dodgy operators’ and negative media attention as limitations. Other constraints to emerge related to government and policy barriers. These were reflected in comments about the collection by government of fees from licensees and better ‘powers’ for police to deal with offenders. The fourth and final key theme that emerged from Study Three related to the opportunities for and capability of police to leverage off external partnerships to reduce harms inside and outside licensed premises. Not surprisingly, participants had a comprehensive knowledge of a broad range of stakeholders, from a diversity of contexts, influential in addressing issues in licensed premises. Many participants reported their relationships with the police and other stakeholders as effective, productive and consistent with the objectives of partnering to reduce alcohol-related harm. On the other hand, there were those who were concerned with their relationship with other stakeholders, particularly those with a compliance function (e.g. Office of Liquor & Gaming Regulation [OLGR]). The resourcing limitations of partners and stakeholders were also raised as an important constraining factor in fulfilling the optimum relationship. Again, political issues were mentioned in terms of the impact on partnerships, with participants stating that there is at times political interference and that politicians complicate the relationships of stakeholders. There are some significant strengths with respect to the methodology of this research. The research is distinguished from previous work in that it examines these critical issues from three distinct perspectives (i.e. police officer, senior manager and external stakeholder). Other strengths relate to the strong theoretical framework that guides and informs the research. There are also some identified limitations, including the subjective nature of self-report data as well as the potential for bias by the author, which was controlled for using a range of initiatives. A further limitation concerns the potential for transferability and generalisability of the findings to other locations given the distinctive nature of the BCD. These limitations and issues of transferability are dealt with at length in the thesis. Despite a growing body of literature about contextual harms associated with alcohol, and specific research concerning police intervention in such contextual harms, there is still much to learn. While research on the subject of police engaging in alcohol-related incidents has focused on police behaviours and strategies in response to such issues, there is a paucity of research that focuses on the knowledge and understanding of officers engaged in such behaviours and practices. Given the scarcity of research dealing with the knowledge, skills and attitudes of police officers responding to harms inside and outside licensed premises, this research contributes significantly to what is a recent and growing body of research and literature in the field. The research makes a practical contribution to police agencies’ understanding of officer knowledge and police practice in ways that have the potential to shape education and training agendas, policy approaches around generalist versus specialist policing, strategic and operational strategy, as well as partnership engagements. The research also makes a theoretical contribution given that the research design is informed by the Three Circle