985 resultados para line efficiency


Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper we present a fast power line detection and localisation algorithm as well as propose a high-level guidance architecture for active vision-based Unmanned Aerial Vehicle (UAV) guidance. The detection stage is based on steerable filters for edge ridge detection, followed by a line fitting algorithm to refine candidate power lines in images. The guidance architecture assumes an UAV with an onboard Gimbal camera. We first control the position of the Gimbal such that the power line is in the field of view of the camera. Then its pose is used to generate the appropriate control commands such that the aircraft moves and flies above the lines. We present initial experimental results for the detection stage which shows that the proposed algorithm outperforms two state-of-the-art line detection algorithms for power line detection from aerial imagery.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To investigate the effects of adopting a pull system in assembly lines in contrast to a push system, simulation software called “ARENA” is used as a tool in order to present numerical results from both systems. Simulation scenarios are created to evaluate the effects of attributes changing in assembly systems, with influential factors including the change of manufacturing system (push system to pull system) and variation of demand. Moreover, pull system manufacturing consists of the addition attribute, which is the number of buffer storage. This paper will provide an analysis based on a previous case study, hence process time and workflow refer to the journal name “Optimising and simulating the assembly line balancing problem in a motorcycle manufacturing company: a case study” [2]. The implementation of the pull system mechanism is to produce a system improvement in terms of the number of Work-In-Process (WIP), total time of products in the system, and the number of finished product inventory, while retaining the same throughput.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study investigated the effect of engine backpressure on the performance and emissions of a CI engine under different speed and load conditions. A 4-stroke single cylinder naturally aspirated direct injection (DI) diesel engine was used for the investigation with the backpressure of 0, 40, 60 and 80 mm of Hg at engine speed of 600, 950 and 1200 rpm. Two parameters were measured during the engine operation: one is engine performance (brake thermal efficiency and brake specific fuel consumption), and the other is the exhaust emissions (NOx, CO and odor). NOx and CO emission were measured by flue gas analyzer (IMR 1400). The engine backpressure produced by the flow regulating valve in the exhaust line was measured by Hg (mercury) manometer. The result showed that, the brake thermal efficiency and brake specific fuel consumption (bsfc) are almost unchanged with increasing backpressure up to 40 mm of Hg pressure for all engine speed and load conditions. The NOx emission became constant or a little decreased with increasing backpressure. The formation of CO was slightly higher with increase of load and back pressure at low engine speed condition. However, under high speed conditions, CO reduced significantly with increasing backpressure for all load conditions. The odor level was similar or a little higher with increasing backpressure for all engine speed and load conditions. Hence, backpressure up to a certain level is not detrimental for a CI engine.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A baculovirus-insect cell expression system potentially provides the means to produce prophylactic HIV-1 virus-like particle (VLP) vaccines inexpensively and in large quantities. However, the system must be optimized to maximize yields and increase process efficiency. In this study, we optimized the production of two novel, chimeric HIV-1 VLP vaccine candidates (GagRT and GagTN) in insect cells. This was done by monitoring the effects of four specific factors on VLP expression: these were insect cell line, cell density, multiplicity of infection (MOI), and infection time. The use of western blots, Gag p24 ELISA, and four-factorial ANOVA allowed the determination of the most favorable conditions for chimeric VLP production, as well as which factors affected VLP expression most significantly. Both VLP vaccine candidates favored similar optimal conditions, demonstrating higher yields of VLPs when produced in the Trichoplusia ni Pro insect cell line, at a cell density of 1 × 106 cells/mL, and an infection time of 96 h post infection. It was found that cell density and infection time were major influencing factors, but that MOI did not affect VLP expression significantly. This work provides a potentially valuable guideline for HIV-1 protein vaccine optimization, as well as for general optimization of a baculovirus-based expression system to produce complex recombinant proteins. © 2009 American Institute of Chemical Engineers.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Airports and cities inevitably recognise the value that each brings the other; however, the separation in decision-making authority for what to build, where, when and how provides a conundrum for both parties. Airports often want a say in what is developed outside of the airport fence, and cities often want a say in what is developed inside the airport fence. Defining how much of a say airports and cities have in decisions beyond their jurisdictional control is likely to be a topic that continues so long as airports and cities maintain separate formal decision-making processes for what to build, where, when and how. However, the recent Green and White Papers for a new National Aviation Policy have made early inroads to formalising relationships between Australia’s major airports and their host cities. At present, no clear indication (within practice or literature) is evident to the appropriateness of different governance arrangements for decisions to develop in situations that bring together the opposing strategic interests of airports and cities; thus leaving decisions for infrastructure development as complex decision-making spaces that hold airport and city/regional interests at stake. The line of enquiry is motivated by a lack of empirical research on networked decision-making domains outside of the realm of institutional theorists (Agranoff & McGuire, 2001; Provan, Fish & Sydow, 2007). That is, governance literature has remained focused towards abstract conceptualisations of organisation, without focusing on the minutia of how organisation influences action in real-world applications. A recent study by Black (2008) has provided an initial foothold for governance researchers into networked decision-making domains. This study builds upon Black’s (2008) work by aiming to explore and understand the problem space of making decisions subjected to complex jurisdictional and relational interdependencies. That is, the research examines the formal and informal structures, relationships, and forums that operationalise debates and interactions between decision-making actors as they vie for influence over deciding what to build, where, when and how in airport-proximal development projects. The research mobilises a mixture of qualitative and quantitative methods to examine three embedded cases of airport-proximal development from a network governance perspective. Findings from the research provide a new understanding to the ways in which informal actor networks underpin and combine with formal decision-making networks to create new (or realigned) governance spaces that facilitate decision-making during complex phases of development planning. The research is timely, and responds well to Isett, Mergel, LeRoux, Mischen and Rethemeyer’s (2011) recent critique of limitations within current network governance literature, specifically to their noted absence of empirical studies that acknowledge and interrogate the simultaneity of formal and informal network structures within network governance arrangements (Isett et al., 2011, pp. 162-166). The combination of social network analysis (SNA) techniques and thematic enquiry has enabled findings to document and interpret the ways in which decision-making actors organise to overcome complex problems for planning infrastructure. An innovative approach to using association networks has been used to provide insights to the importance of the different ways actors interact with one another, thus providing a simple yet valuable addition to the increasingly popular discipline of SNA. The research also identifies when and how different types of networks (i.e. formal and informal) are able to overcome currently known limitations to network governance (see McGuire & Agranoff, 2011), thus adding depth to the emerging body of network governance literature surrounding limitations to network ways of working (i.e. Rhodes, 1997a; Keast & Brown, 2002; Rethemeyer & Hatmaker, 2008; McGuire & Agranoff, 2011). Contributions are made to practice via the provision of a timely understanding of how horizontal fora between airports and their regions are used, particularly in the context of how they reframe the governance of decision-making for airport-proximal infrastructure development. This new understanding will enable government and industry actors to better understand the structural impacts of governance arrangements before they design or adopt them, particularly for factors such as efficiency of information, oversight, and responsiveness to change.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Given the importance of water for rice production, this study examines the factors affecting the technical efficiency (TE) of irrigated rice farmers in village irrigation systems (VIS) in Sri Lanka. Primary data were collected from 460 rice farmers in the Kurunagala District, Sri Lanka, to estimate a stochastic translog production frontier for rice production. The mean TE of rice farming in village irrigation was found to be 0.72, although 63% of rice farmers exceeded this average. The most influential factors of TE are membership of Farmer Organisations (FOs) and the participatory rate in collective actions organised by FOs. The results suggest that enhancement of co-operative arrangements of farmers by strengthening the membership of FOs is considered important for increasing TE in rice farming in VIS.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Attentional Control Theory (ACT) proposes that high-anxious individuals maintain performance effectiveness (accuracy) at the expense of processing efficiency (response time), in particular, the two central executive functions of inhibition and shifting. In contrast, research has generally failed to consider the third executive function which relates to the function of updating. In the current study, seventy-five participants completed the Parametric Go/No-Go and n-back tasks, as well as the State-Trait Anxiety Inventory in order to explore the effects of anxiety on attention. Results indicated that anxiety lead to decay in processing efficiency, but not in performance effectiveness, across all three Central Executive functions (inhibition, set-shifting and updating). Interestingly, participants with high levels of trait anxiety also exhibited impaired performance effectiveness on the n-back task designed to measure the updating function. Findings are discussed in relation to developing a new model of ACT that also includes the role of preattentive processes and dual-task coordination when exploring the effects of anxiety on task performance.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper presents an input-orientated data envelopment analysis (DEA) framework which allows the measurement and decomposition of economic, environmental and ecological efficiency levels in agricultural production across different countries. Economic, environmental and ecological optimisations search for optimal input combinations that minimise total costs, total amount of nutrients, and total amount of cumulative exergy contained in inputs respectively. The application of the framework to an agricultural dataset of 30 OECD countries revealed that (i) there was significant scope to make their agricultural production systemsmore environmentally and ecologically sustainable; (ii) the improvement in the environmental and ecological sustainability could be achieved by being more technically efficient and, even more significantly, by changing the input combinations; (iii) the rankings of sustainability varied significantly across OECD countries within frontier-based environmental and ecological efficiency measures and between frontier-based measures and indicators.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Significant wheel-rail dynamic forces occur because of imperfections in the wheels and/or rail. One of the key responses to the transmission of these forces down through the track is impact force on the sleepers. Dynamic analysis of nonlinear systems is very complicated and does not lend itself easily to a classical solution of multiple equations. Trying to deduce the behaviour of track components from experimental data is very difficult because such data is hard to obtain and applies to only the particular conditions of the track being tested. The finite element method can be the best solution to this dilemma. This paper describes a finite element model using the software package ANSYS for various sized flat defects in the tread of a wheel rolling at a typical speed on heavy haul track. The paper explores the dynamic response of a prestressed concrete sleeper to these defects.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Knowledge of cable parameters has been well established but a better knowledge of the environment in which the cables are buried lags behind. Research in Queensland University of Technology has been aimed at obtaining and analysing actual daily field values of thermal resistivity and diffusivity of the soil around power cables. On-line monitoring systems have been developed and installed with a data logger system and buried spheres that use an improved technique to measure thermal resistivity and diffusivity over a short period. Results based on long term continuous field data are given. A probabilistic approach is developed to establish the correlation between the measured field thermal resistivity values and rainfall data from weather bureau records. This data from field studies can reduce the risk in cable rating decisions and provide a basis for reliable prediction of “hot spot” of an existing cable circuit

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The implementation guide for the surveillance of CLABSI in intensive care units (ICU) was produced by the Healthcare Associated Infection (HAI) Technical Working Group of the Australian Commission on Safety and Quality in Health Care(ACSQHC), and endorsed by the ACSQHC HAI Advisory Committee. State surveillance units, the ACSQHC and the Australian and New Zealand Intensive Care Society (ANZICS) have representatives on the Technical Working Group, and have provided input into this document.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A short 27 mins docudrama film. The Brisbane Line is a neo noir drama-documentary depicting the forgotten history surrounding the subtropical capital of Queensland, Australia. Set in the shadows of this sunshine city's unsolved crime, the film explores gaps between fact and fiction, memory and myth and excavates Brisbane's original sin [from DVD container]. The Brisbane Line is a film noir about the 1940s police force & corruption in Brisbane. The film is a creative research output, screened at Tribal Cinemas, Brisbane on the 8th November 2011.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The project examined the responsiveness of the telenursing service provided by the Child Health Line (hereinafter referred to as CHL). It aimed to provide an account of population usage of the service, the call request types and the response of the service to the calls. In so doing, the project extends the current body of knowledge pertaining to the provision of parenting support through telenursing. Approximately 900 calls to the CHL were audio-recorded over the December 2005-2006 Christmas-New Year period. A protocol was developed to code characteristics of the call, the interactional features between the caller and nurse call-taker, and the extent to which there was (a) agreement on problem definition and the plan of action and (b) interactional alignment between nurse and caller. A quantitative analysis examined the frequencies of the main topics covered in calls to the CHL and any statistical associations between types of calls, length of calls and nurse-caller alignment. In addition, a detailed qualitative analysis was conducted on a subset of calls dealing with the nurse management of calls seeking medical advice and information. Key findings include: • Overall, 74% of the calls discussed parenting and child development issues, 48% discussed health/medical issues, and 16% were information-seeking calls. • More specifically: o 21% discussed health/medical and parenting and child development issues. o 3% discussed parenting and information-seeking issues. o 5% discussed health/medical, parenting/development and information issues. o 18% exclusively focussed on health and medical issues and therefore were outside the remit of the intended scope of the CHL. These calls caused interactional dilemmas for the nurse call-takers as they simultaneously dealt with parental expectations for help and the CHL guidelines indicating that offering medical advice was outside the remit of the service. • Most frequent reasons for calling were to discuss sleep, feeding, normative infant physical functions and parenting advice. • The average length of calls to the CHL was 7 minutes. • Longer calls were more likely to involve nurse call-takers giving advice on more than one topic, the caller displaying strong emotions, the caller not specifically providing the reason for the call, and the caller discussing parenting and developmental issues. • Shorter calls were characterised by the nurse suggesting that the child receive immediate medical attention, the nurse emphasising the importance or urgency of the plan of action, the caller referring to or requesting confirmation of a diagnosis, and caller and nurse call-taker discussion of health and medical issues. • The majority of calls, 92%, achieved parent-nurse alignment by the conclusion of the call. However, 8% did not. • The 8% of calls that were not aligned require further quantitative and qualitative investigation of the interactional features. The findings are pertinent in the current context where Child Health Line now resides within 13HEALTH. These findings indicate: 1. A high demand for parenting advice. 2. Nurse call-takers have a high level of competency in dealing with calls about parenting and normal child development, which is the remit of the CHL. 3. Nurse call-takers and callers achieve a high degree of alignment when both parties agree on a course of action. 4. There is scope for developing professional practice in calls that present difficulties in terms of call content, interactional behaviour and call closure. Recommendations of the project: 1. There are numerous opportunities for further research on interactional aspects of calls to the CHL, such as further investigations of the interactional features and the association of the features to alignment and nonalignment. The rich and detailed insights into the patterns of nurse-parent interactions were afforded by the audio-recording and analysis of calls to the CHL. 2. The regular recording of calls would serve as a way of increasing understanding of the type and nature of calls received, and provide a valuable training resource. Recording and analysing calls to CHL provides insight into the operation of the service, including evidence about the effectiveness of triaging calls. 3. Training in both recognising and dealing with problem calls may be beneficial. For example, calls where the caller showed strong emotion, appeared stressed, frustrated or troubled were less likely to be rated as aligned calls. In calls where the callers described being ‘at their wits end’, or responded to each proposed suggestion with ‘I’ve tried that’, the callers were fairly resistant to advice-giving. 4. Training could focus on strategies for managing calls relating to parenting support and advice, and parental well-being. The project found that these calls were more likely to be rated as being nonaligned. 5. With the implementation of 13HEALTH, future research could compare nurse-parent interaction following the implementation of triaging. Of the calls, 21% had both medical and parenting topics discussed and 5.3% discussed medical, parenting and information topics. Added to this, in 12% of calls, there was ambiguity between the caller and nurse call-taker as to whether the problem was medical or behavioural.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A pressing cost issue facing construction is the procurement of off-site pre-manufactured assemblies. In order to encourage Australian adoption of off-site manufacture (OSM), a new approach to underlying processes is required. The advent of object oriented digital models for construction design assumes intelligent use of data. However, the construction production system relies on traditional methods and data sources and is expected to benefit from the application of well-established business process management techniques. The integration of the old and new data sources allows for the development of business process models which, by capturing typical construction processes involving OSM, provides insights into such processes. This integrative approach is the foundation of research into the use of OSM to increase construction productivity in Australia. The purpose of this study is to develop business process models capturing the procurement, resources and information flow of construction projects. For each stage of the construction value chain, a number of sub-processes are identified. Business Process Modelling Notation (BPMN), a mainstream business process modelling standard, is used to create base-line generic construction process models. These models identify OSM decision-making points that could provide cost reductions in procurement workflow and management systems. This paper reports on phase one of an on-going research aiming to develop a proto-type workflow application that can provide semi-automated support to construction processes involving OSM and assist in decision-making in the adoption of OSM thus contributing to a sustainable built environment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Security of RFID authentication protocols has received considerable interest recently. However, an important aspect of such protocols that has not received as much attention is the efficiency of their communication. In this paper we investigate the efficiency benefits of pre-computation for time-constrained applications in small to medium RFID networks. We also outline a protocol utilizing this mechanism in order to demonstrate the benefits and drawbacks of using thisapproach. The proposed protocol shows promising results as it is able to offer the security of untraceableprotocols whilst only requiring the time comparable to that of more efficient but traceable protocols.