952 resultados para evaluation algorithm


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The primary objective of this study is to develop a robust queue estimation algorithm for motorway on-ramps. Real-time queue information is a vital input for dynamic queue management on metered on-ramps. Accurate and reliable queue information enables the management of on-ramp queue in an adaptive manner to the actual traffic queue size and thus minimises the adverse impacts of queue flush while increasing the benefit of ramp metering. The proposed algorithm is developed based on the Kalman filter framework. The fundamental conservation model is used to estimate the system state (queue size) with the flow-in and flow-out measurements. This projection results are updated with the measurement equation using the time occupancies from mid-link and link-entrance loop detectors. This study also proposes a novel single point correction method. This method resets the estimated system state to eliminate the counting errors that accumulate over time. In the performance evaluation, the proposed algorithm demonstrated accurate and reliable performances and consistently outperformed the benchmarked Single Occupancy Kalman filter (SOKF) method. The improvements over SOKF are 62% and 63% in average in terms of the estimation accuracy (MAE) and reliability (RMSE), respectively. The benefit of the innovative concepts of the algorithm is well justified by the improved estimation performance in congested ramp traffic conditions where long queues may significantly compromise the benchmark algorithm’s performance.

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This paper proposes a unique and innovative approach to integrate transit signal priority control into a traffic adaptive signal control strategy. The proposed strategy was named OSTRAC (Optimized Strategy for integrated TRAffic and TRAnsit signal Control). The cornerstones of OSTRAC include an online microscopic traffic f low prediction model and a Genetic Algorithm (GA) based traffic signal timing module. A sensitivity analysis was conducted to determine the critical GA parameters. The developed traffic f low model demonstrated reliable prediction results through a test. OSTRAC was evaluated by comparing its performance to three other signal control strategies. The evaluation results revealed that OSTRAC efficiently and effectively reduced delay time of general traffic and also transit vehicles.

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Fibrous scaffolds of engineered structures can be chosen as promising porous environments when an approved criterion validates their applicability for a specific medical purpose. For such biomaterials, this paper sought to investigate various structural characteristics in order to determine whether they are appropriate descriptors. A number of poly(3-hydroxybutyrate) scaffolds were electrospun; each of which possessed a distinguished architecture when their material and processing conditions were altered. Subsequent culture of mouse fibroblast cells (L929) was carried out to evaluate the cells viability on each scaffold after their attachment for 24 h and proliferation for 48 and 72 h. The scaffolds’ porosity, pores number, pores size and distribution were quantified and none could establish a relationship with the viability results. Virtual reconstruction of the mats introduced an authentic criterion, “Scaffold Percolative Efficiency” (SPE), with which the above descriptors were addressed collectively. It was hypothesized to be able to quantify the efficacy of fibrous scaffolds by considering the integration of porosity and interconnectivity of the pores. There was a correlation of 80% as a good agreement between the SPE values and the spectrophotometer absorbance of viable cells; a viability of more than 350% in comparison to that of the controls.

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Although topic detection and tracking techniques have made great progress, most of the researchers seldom pay more attention to the following two aspects. First, the construction of a topic model does not take the characteristics of different topics into consideration. Second, the factors that determine the formation and development of hot topics are not further analyzed. In order to correctly extract news blog hot topics, the paper views the above problems in a new perspective based on the W2T (Wisdom Web of Things) methodology, in which the characteristics of blog users, context of topic propagation and information granularity are investigated in a unified way. The motivations and features of blog users are first analyzed to understand the characteristics of news blog topics. Then the context of topic propagation is decomposed into the blog community, topic network and opinion network, respectively. Some important factors such as the user behavior pattern, opinion leader and network opinion are identified to track the development trends of news blog topics. Moreover, a blog hot topic detection algorithm is proposed, in which news blog hot topics are identified by measuring the duration, topic novelty, attention degree of users and topic growth. Experimental results show that the proposed method is feasible and effective. These results are also useful for further studying the formation mechanism of opinion leaders in blogspace.

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Drink driving is a major public health issue and this report examines the experiences of convicted offenders who participated in an established drink driving rehabilitation program Under the Limit (UTL). Course completers were surveyed at least three months after they had finished the 11-week UTL course. The aim of this study was to examine whether the UTL program reduced the level of alcohol consumption either directly as a result of participation in the UTL drink driving program or through increased use of community alcohol program by participants. The research involved a self-report outcome evaluation to determine whether the self-reported levels of alcohol use after the course had changed from the initial alcohol use reported by offenders. The findings are based on the responses of 30 drink-driving offenders who had completed the UTL program (response rate: 20%). While a process evaluation was proposed in the initial application, the low response rate meant that this follow up research was not feasible. The response rate was low for two reasons, it was difficult to: recruit participants who consented to follow up, and subsequently locate and survey those who had consented to involvement.

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In 2005 the Australian Capital Territory (ACT) Office of the Director of Public Prosecutions (DPP) and the Australian Federal Police (AFP) produced a report, Responding to sexual assault: The challenge of change (DPP & AFP 2005), which made 105 recommendations for reforming the way sexual offence cases are handled by the ACT’s criminal justice system. The Sexual Assault Reform Program (SARP) is one key initiative developed in response to these recommendations. Managed by the ACT Justice and Community Safety Directorate (JACS), SARP’s main objective is to improve aspects of the criminal justice system relating to: processes and support for victims of sexual offences as they progress through the system; attrition in sexual offence matters in the criminal justice system; and coordination and collaboration among the agencies involved. In November 2007 the ACT Attorney-General announced $4 million of funding for several SARP reforms. This funding provided for additional victim support staff; a dedicated additional police officer, prosecutor and legal policy officer; and an upgrade of equipment for the Supreme Court and Magistrates Court, including improvements in technology to assist witnesses in giving evidence, and the establishment of an off-site facility to allow witnesses to give evidence from a location outside of the court. In addition, the reform agenda included a number of legislative amendments that changed how evidence can be given by victims of sexual and family violence offences, children and other vulnerable witnesses. The primary objectives of these legislative changes are to provide an unintimidating, safe environment for vulnerable witnesses (including sexual offence complainants) to give evidence and to obtain prompt statements from witnesses to improve the quality of evidence captured (DPP 2009: 13). The current evaluation The funding for SARP reforms also provided for a preliminary evaluation of the reforms; this report outlines findings from the evaluation. The evaluation sought to address whether the program has met its key objectives: better support for victims, lower attrition rates and improved coordination and collaboration among agencies involved in administering SARP. The evaluation was conducted in two stages and involved a mixed-methods approach. During stage 1 key indicators for the evaluation were developed with stakeholders. During stage 2 quantitative data were collected by stakeholders and provided to the AIC for analysis. Qualitative interviews were also conducted with service delivery providers, and with a small number (n=5) of victim/survivors of sexual offences whose cases had recently been resolved in the ACT criminal justice system. The current evaluation is preliminary in nature. As the SARP reforms will take time to become entrenched within the ACT’s criminal justice system, some of the impacts of the reforms may not yet be evident. Nonetheless, this evaluation provides an insight into how well the SARP reforms have been implemented to date, as well as key areas that could be addressed in the future. Key findings from the preliminary evaluation are outlined briefly below.

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Several approaches have been introduced in literature for active noise control (ANC) systems. Since FxLMS algorithm appears to be the best choice as a controller filter, researchers tend to improve performance of ANC systems by enhancing and modifying this algorithm. This paper proposes a new version of FxLMS algorithm. In many ANC applications an online secondary path modelling method using a white noise as a training signal is required to ensure convergence of the system. This paper also proposes a new approach for online secondary path modelling in feedfoward ANC systems. The proposed algorithm stops injection of the white noise at the optimum point and reactivate the injection during the operation, if needed, to maintain performance of the system. Benefiting new version of FxLMS algorithm and not continually injection of white noise makes the system more desirable and improves the noise attenuation performance. Comparative simulation results indicate effectiveness of the proposed approach.

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This is a summative evaluation of the Stronger Smarter Learning Communities (SSLC) project that examines whether and how the SSLC project had an impact on Australian state schools which adopted its models and approaches. Drawing from qualitative and quantitative data sets, it also presents the largest scale and most comprehensive analysis of Indigenous education practices and outcomes to date. It includes empirical findings on: success in changing school ethos and community engagement; challenges in progress at closure of the 'gap' in conventionally measured achievement and performance; schools' and principals' choices in curriculum and instruction; profiles of teachers' and principals' training and views on teacher education; and a strong emphasis on community and school Indigenoous voices and views on Indigenous education.

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Objective: To investigate the density of the primary epidermal lamellae (PEL) around the solar circumference of the forefeet of near-term fetal feral and nonferal (ie, domesticated) horses. Sample: Left forefeet from near-term Australian feral (n = 14) and domesticated (4) horse fetuses. Procedures: Near-term feral horse fetuses were obtained from culled mares within 10 minutes of death; fetuses that had died in utero 2 weeks prior to anticipated birth date and were delivered from live Thoroughbred mares were also obtained. Following disarticulation at the carpus, the left forefoot of each fetus was frozen during dissection and data collection. In a standard section of each hoof, the stratum internum PEL density was calculated at the midline center (12 o'clock) and the medial and lateral break-over points (11 and 1 o'clock), toe quarters (10 and 2 o'clock), and quarters (4 and 6 o'clock). Values for matching lateral and medial zones were averaged and expressed as 1 density. Density differences at the 4 locations between the feral and domesticated horse feet were assessed by use of imaging software analysis. Results: In fetal domesticated horse feet, PEL density did not differ among the 4 locations. In fetal feral horse feet, PEL density differed significantly among locations, with a pattern of gradual reduction from the dorsal to the palmar aspect of the foot. The PEL density distribution differed significantly between fetal domesticated and feral horse feet. Conclusions and Clinical Relevance: Results indicated that PEL density distribution differs between fetal feral and domesticated horse feet, suggestive of an adaptation of feral horses to environment challenges.

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The purpose of this study was to evaluate aspects of participation in a participatory action research project, the Ashgrove Healthy School Environment Project. Participatory action research is a form of research that creates change as an explicit part of the research process and requires the active participation of those by and for whom the research is being conducted. This study arose from concems by this researcher, who is also a co-facilitator of the project, that levels of participation were not as extensive as one might have hoped and that this seemingly low level would have a negative impact on the continuing participation of those already involved. Specifically. this evaluation sought to uncover the reasons that prompted participation, to identify structural barriers to initial involvement and to uncover participants' perceptions of the process, including barriers and opportunities. It also sought to record evidence of any shift in decision making and to draw implications about the findings that could assist the project, the school, other schools and the wider community. This evaluation involved focus group discussions and interviews with participants actively involved in the school project. The purpose was to uncover their views, feelings and perceptions about their participation and the participatory processes in use generally. It also included some examination of school documents and newsletters and as also drawn on the reflections of this 'insider' researcher, based on two years of involvement in facilitating the project. The findings that emerge from this study are heartening. Rather than feeling anxious about the long-term sustainability of the project, this researcher now feels more confident about its achievements, both in terms of the changes that have occurred in the school and about the participatory processes and levels of participation. Whilst the evaluation has identified a number of barriers, both institutional, personal and project related, it has also identified several key factors that serve to promote participation.

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A theoretical framework for a construction management decision evaluation system for project selection by means of a literature review. The theory is developed by the examination of the major factors concerning the project selection decision from a deterministic viewpoint, where the decision-maker is assumed to possess 'perfect knowledge' of all the aspects involved. Four fundamental project characteristics are identified together with three meaningful outcome variables. The relationship within and between these variables are considered together with some possible solution techniques. The theory is next extended to time-related dynamic aspects of the problem leading to the implications of imperfect knowledge and a non­deterministic model. A solution technique is proposed in which Gottinger's sequential machines are utilised to model the decision process,

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This paper describes the development and validation of a PC based MUARC Driver Distraction Test designed to measure simulated driving performance while the driver is performing a secondary task. The paper discusses the logic behind the development of the test, including the principles that were used to guide its design, as well as the results of a pilot validation study. The findings from this study were consistent with previous research and theory and were consistent with those obtained with the LCT. The results did, however, highlight a number of refinements that were necessary to improve the utility of the test.

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Advanced composite materials offer remarkable potential in the strengthening of Civil Engineering structures. This research is targeted to provide in depth knowledge and understanding of bond characteristics of advanced and corrosion resistant material carbon fibre reinforced polymer (CFRP) that has a unique design tailor-ability and cost effective nature. The objective of this research is to investigate and compare the bonding mechanism between CFRP strengthened single and double strap steel joints. Investigations have been made in regards to failure mode, ultimate load and effective bond length for CFRP strengthened double and single strap joints. A series of tensile tests were conducted with different bond lengths for both type of joints. The bond behaviour of these specimens was further investigated by using nonlinear finite element analysis. Finally a bilinear relationship of shear stress-slip has been proposed by using the Finite element model for single and double strap joints.