914 resultados para synchronous-transit


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This poster introduces Passenger Relative Load Factor for a route or individual bus service as a capacity and quality of service measure, distinguishing it from Occupancy Load Factor. It introduces Load Diversity Coefficient as the ratio of Passenger Relative Load Factor to Occupancy Load Factor, and relates Load Diversity Coefficient to Coefficient of Variation in Occupancy Load Factor. It qualifies the operator’s and passengers’ perspectives of load factor based on Coefficient of Variation in Occupancy Load Factor along a route. A case study using weekday Automatic Fare Collection (AFC) data on a premium bus line in Brisbane, Australia illustrates the methodology. The compendium paper also qualifies the operator’s and passengers’ perspectives of these load factors along with Passengers’ Average Travel Time for capacity and quality of service assessment.

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Context. Irregular plagues of house mice cause high production losses in grain crops in Australia. If plagues can be forecast through broad-scale monitoring or model-based prediction, then mice can be proactively controlled by poison baiting. Aims. To predict mouse plagues in grain crops in Queensland and assess the value of broad-scale monitoring. Methods. Regular trapping of mice at the same sites on the Darling Downs in southern Queensland has been undertaken since 1974. This provides an index of abundance over time that can be related to rainfall, crop yield, winter temperature and past mouse abundance. Other sites have been trapped over a shorter time period elsewhere on the Darling Downs and in central Queensland, allowing a comparison of mouse population dynamics and cross-validation of models predicting mouse abundance. Key results. On the regularly trapped 32-km transect on the Darling Downs, damaging mouse densities occur in 50% of years and a plague in 25% of years, with no detectable increase in mean monthly mouse abundance over the past 35 years. High mouse abundance on this transect is not consistently matched by high abundance in the broader area. Annual maximum mouse abundance in autumn–winter can be predicted (R2 = 57%) from spring mouse abundance and autumn–winter rainfall in the previous year. In central Queensland, mouse dynamics contrast with those on the Darling Downs and lack the distinct annual cycle, with peak abundance occurring in any month outside early spring.Onaverage, damaging mouse densities occur in 1 in 3 years and a plague occurs in 1 in 7 years. The dynamics of mouse populations on two transects ~70 km apart were rarely synchronous. Autumn–winter rainfall can indicate mouse abundance in some seasons (R2 = ~52%). Conclusion. Early warning of mouse plague formation in Queensland grain crops from regional models should trigger farm-based monitoring. This can be incorporated with rainfall into a simple model predicting future abundance that will determine any need for mouse control. Implications. A model-based warning of a possible mouse plague can highlight the need for local monitoring of mouse activity, which in turn could trigger poison baiting to prevent further mouse build-up.

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This thesis makes a significant contribution to knowledge and understanding of 'Human Travel Behaviour' in relation to transportation research. It holds some important merits that have not been proposed before. It develops a new, comprehensive and meaningful relationship that includes bus transit ridership change due to weather variables, seasonality and transit quality of service within a single daily ridership rate estimation model. The research incorporated both temporal and spatial influences on ridership within a modelling structure, named as the Nested Model Structure. It provides a complete picture of ridership variation across the sub-tropical city of Brisbane, Australia.

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A novel ethylene-α-cyclodextrin (α-CD) inclusion complex (IC) powder was investigated to ripen Calypso mango fruit. Modulated release of ethylene gas from the IC powder was achieved by admixture with deliquescent salt CaCl2 at RHs of 75.5% and 93.6%. The IC powder was tested in the laboratory and for in-transit ripening of mango fruit over two seasons. In the laboratory experiment, ethylene gas started to release from the IC powder in 2 h and complete release was achieved in 24 h. Assessments of fruit colour and firmness showed that encapsulated ethylene and commercial grade ethylene from pressurised cylinder similarly shortened the ripening time to 9–10 days (after harvest) for treated fruit as compared with 15 days for untreated mango. Mango fruit treated in both ways with ethylene showed more uniform ripening than the control. For the in-transit ripening using the IC powder, ethylene was found to be between 4.9 and 10.5 μL L−1 in the headspace of the truck containers over 48 h. Mango fruit from the treated containers shortened the ripening time by 3–6 days as compared to the untreated control fruit. Thus, the safe and convenient IC powder has demonstrated promise for in-transit fruit ripening.

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The objective of this paper is to discuss some hardware and software features of an experimental network of 8080 and 8085 microcomputers named Micronet. The interprocessor communication in the ring network is established using ring interfaces consisting of universal synchronous-asynchronous receivers-transmitters (USARTs). Another aspect considered is the interfacing of an 8080 microcomputer to a PDP-11/35 minicomputer and the development of the software for the microcomputer-minicomputer link which has been established over a serial line using the USART interface of the microcomputer and the DZ11 module of the minicomputer. This is useful in developing a host-satellite configuration of microcomputers and the minicomputer.

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Australian forest industries have a long history of export trade of a wide range of products from woodchips(for paper manufacturing), sandalwood (essential oils, carving and incense) to high value musical instruments, flooring and outdoor furniture. For the high value group, fluctuating environmental conditions brought on by changes in mperature and relative humidity, can lead to performance problems due to consequential swelling, shrinkage and/or distortion of the wood elements. A survey determined the types of value-added products exported, including species and dimensions packaging used and export markets. Data loggers were installed with shipments to monitor temperature and relative humidity conditions. These data were converted to timber equilibrium moisture content values to provide an indication of the environment that the wood elements would be acclimatising to. The results of the initial survey indicated that primary high value wood export products included guitars, flooring, decking and outdoor furniture. The destination markets were mainly located in the northern hemisphere, particularly the United States of America, China, Hong Kong, Europe including the United Kingdom), Japan, Korea and the Middle East. Other regions importing Australian-made wooden articles were south-east Asia, New Zealand and South Africa. Different timber species have differing rates of swelling and shrinkage, so the types of timber were also recorded during the survey. Results from this work determined that the major species were ash-type eucalypts from south-eastern Australia (commonly referred to in the market as Tasmanian oak), jarrah from Western Australia, spotted gum, hoop pine, white cypress, black butt, brush box and Sydney blue gum from Queensland and New South Wales. The environmental conditions data indicated that microclimates in shipping containers can fluctuate extensively during shipping. Conditions at the time of manufacturing were usually between 10 and 12% equilibrium moisture content, however conditions during shipping could range from 5 (very dry) to 20% (very humid). The packaging systems incorporated were reported to be efficient at protecting the wooden articles from damage during transit. The research highlighted the potential risk for wood components to ‘move’ in response to periods of drier or more humid conditions than those at the time of manufacturing, and the importance of engineering a packaging system that can account for the environmental conditions experienced in shipping containers. Examples of potential dimensional changes in wooden components were calculated based on published unit shrinkage data for key species and the climatic data returned from the logging equipment. The information highlighted the importance of good design to account for possible timber movement during shipping. A timber movement calculator was developed to allow designers to input component species, dimensions, site of manufacture and destination, to see validate their product design. This calculator forms part of the free interactive website www.timbers.com.au.

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A5-GMR-1 is a synchronous stream cipher used to provide confidentiality for communications between satellite phones and satellites. The keystream generator may be considered as a finite state machine, with an internal state of 81 bits. The design is based on four linear feedback shift registers, three of which are irregularly clocked. The keystream generator takes a 64-bit secret key and 19-bit frame number as inputs, and produces an output keystream of length between $2^8$ and $2^{10}$ bits. Analysis of the initialisation process for the keystream generator reveals serious flaws which significantly reduce the number of distinct keystreams that the generator can produce. Multiple (key, frame number) pairs produce the same keystream, and the relationship between the various pairs is easy to determine. Additionally, many of the keystream sequences produced are phase shifted versions of each other, for very small phase shifts. These features increase the effectiveness of generic time-memory tradeoff attacks on the cipher, making such attacks feasible.

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With enrolments in higher education becoming a competitive market, through the removal of caps in 2012, the equitable access to postgraduate education is raised. Postgraduate education, provided through higher education institutions, is an important aspect of career development for professionals. Professionals working outside of the metropolitan area are increasingly seeking postgraduate education opportunities that will be delivered online, at a distance. In this research study, data collected from the teaching profession, has culminated in a model that will ultimately improve access to professional learning. This research paper aims to highlight the important role that higher education providers play in the delivery of postgraduate education to professionals working in regional and remote areas of Australia. Although this paper focuses on the realm of education, the model of connectedness, where synchronous and asynchronous technologies are used, can be adapted and applied to any profession that requires equitable access to professional learning.

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Access to quality higher education is challenging for many Western Australians that live outside the metropolitan area. In 2010, the School of Education moved to flexible delivery of a fully online Bachelor of Education degree for their non -metropolitan students. The new model of delivery allows access for students from any location provided they have a computer and an internet connection. A number of academic staff had previously used an asynchronous environment to deliver learning modules housed within a learning management system (LMS) but had not used synchronous software with their students. To enhance the learning environment and to provide high quality learning experiences to students learning at a distance, the adoption of synchronous software (Elluminate Live) was introduced. This software is a real-time virtual classroom environment that allows for communication through Voice over Internet Protocol (VoIP) and videoconferencing, along with a large number of collaboration tools to engage learners. This research paper reports on the integration of a live e-learning solution into the current LMS environment. Qualitative data were collected from academic staff through informal interviews and participant observation. The findings discuss (i) perceived level of support; (ii) identification of strategies used to create an effective online teacher presence; (iii) the perceived impact on the students' learning outcomes; and (iv) guidelines for professional development to enhance pedagogy within the live e-learning environment.

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Many teachers working in remote and regional areas have limited access to collegial support networks. This research aimed to examine the existing strategies that were being undertaken by the Department of Education in Western Australia, to provide professional learning to teachers in regional and remote areas. It was important to establish the perceptions of teachers’ access to professional learning from those working at the coalface in geographically dispersed areas. Consequently, the possible opportunity for improving the amount and variety of professional learning, through the application of both synchronous and asynchronous technologies was proposed. The study was guided by the primary research question: “In what ways might technology be used to support professional development of regional and remote teachers in Western Australia?” Generating descriptions of current practice of professional learning along with the teacher perceptions were central to this research endeavour. The study relied on a mixed method research approach in order to attend to the research question. The data were collected in phases, referred to as an explanatory mixed methods design. Quantitative data were collected from 104 participants to provide a general picture of the research problem. To further refine this general picture, qualitative data were collected through interviews and e-interviews of 10 teachers. Participants in the study included graduate teachers, teachers who had taught more than two years, senior teachers and Level Three teachers from seven teaching districts within Western Australia. An investigation into current practice was included in this phase and technologies available to support a professional learning community over distance were documented. The final phase incorporated the formulation of a conceptual framework where a model was developed to facilitate the successful implementation of a professional learning community through the application of synchronous and asynchronous technologies. The study has identified that travel time in order to access professional development is significant and impacts on teachers’ personal time. There are limited relief teachers available in these isolated areas which impacts on the opportunities to access professional development. Teachers face inequities, in terms of promotion, because professional development is explicitly linked to promotional opportunities. Importantly, it was found that professional learning communities are valued, but are often limited by small staff numbers at the geographic locality of the school. Teachers preferred to undertake professional learning in the local context of their district, school or classroom and this professional learning must be established at the need of the individual teacher in line with the school priorities. Teachers reported they were confident in using technology and accessing professional development online if required, however, much uncertainty surrounded the use of web 2.0 technologies for this purpose. The recommendations made from the study are intended to identify how a professional learning community might be enhanced through synchronous and asynchronous technologies.

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The quality of an online university degree is paramount to the student, the reputation of the university and most importantly, the profession that will be entered. At the School of Education within Curtin University, we aim to ensure that students within rural and remote areas are provided with high quality degrees equal to their city counterparts who access face-to-face classes on campus.In 2010, the School of Education moved to flexible delivery of a fully online Bachelor of Education degree for their rural students. In previous years, the degree had been delivered in physical locations around the state. Although this served the purpose for the time, it restricted the degree to only those rural students who were able to access the physical campus. The new model in 2010 allows access for students in any rural area who have a computer and an internet connection, regardless of their geographical location. As a result enrolments have seen a positive increase in new students. Academic staff had previously used an asynchronous environment to deliver learning modules housed within a learning management system (LMS). To enhance the learning environment and to provide high quality learning experiences to students learning at a distance, the adoption of synchronous software was introduced. This software is a real-time virtual classroom environment that allows for communication through Voice over Internet Protocol (VoIP) and videoconferencing, along with a large number of collaboration tools to engage learners. This research paper reports on the professional development of academic staff to integrate a live e-learning solution into their current LMS environment. It involved professional development, including technical orientation for teaching staff and course participants simultaneously. Further, pedagogical innovations were offered to engage the students in a collaborative learning environment. Data were collected from academic staff through semi-structured interviews and participant observation. The findings discuss the perceived value of the technology, problems encountered and solutions sought.

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A vast amount of public services and goods are contracted through procurement auctions. Therefore it is very important to design these auctions in an optimal way. Typically, we are interested in two different objectives. The first objective is efficiency. Efficiency means that the contract is awarded to the bidder that values it the most, which in the procurement setting means the bidder that has the lowest cost of providing a service with a given quality. The second objective is to maximize public revenue. Maximizing public revenue means minimizing the costs of procurement. Both of these goals are important from the welfare point of view. In this thesis, I analyze field data from procurement auctions and show how empirical analysis can be used to help design the auctions to maximize public revenue. In particular, I concentrate on how competition, which means the number of bidders, should be taken into account in the design of auctions. In the first chapter, the main policy question is whether the auctioneer should spend resources to induce more competition. The information paradigm is essential in analyzing the effects of competition. We talk of a private values information paradigm when the bidders know their valuations exactly. In a common value information paradigm, the information about the value of the object is dispersed among the bidders. With private values more competition always increases the public revenue but with common values the effect of competition is uncertain. I study the effects of competition in the City of Helsinki bus transit market by conducting tests for common values. I also extend an existing test by allowing bidder asymmetry. The information paradigm seems to be that of common values. The bus companies that have garages close to the contracted routes are influenced more by the common value elements than those whose garages are further away. Therefore, attracting more bidders does not necessarily lower procurement costs, and thus the City should not implement costly policies to induce more competition. In the second chapter, I ask how the auctioneer can increase its revenue by changing contract characteristics like contract sizes and durations. I find that the City of Helsinki should shorten the contract duration in the bus transit auctions because that would decrease the importance of common value components and cheaply increase entry which now would have a more beneficial impact on the public revenue. Typically, cartels decrease the public revenue in a significant way. In the third chapter, I propose a new statistical method for detecting collusion and compare it with an existing test. I argue that my test is robust to unobserved heterogeneity unlike the existing test. I apply both methods to procurement auctions that contract snow removal in schools of Helsinki. According to these tests, the bidding behavior of two of the bidders seems consistent with a contract allocation scheme.

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The paper presents an innovative approach to modelling the causal relationships of human errors in rail crack incidents (RCI) from a managerial perspective. A Bayesian belief network is developed to model RCI by considering the human errors of designers, manufactures, operators and maintainers (DMOM) and the causal relationships involved. A set of dependent variables whose combinations express the relevant functions performed by each DMOM participant is used to model the causal relationships. A total of 14 RCI on Hong Kong’s mass transit railway (MTR) from 2008 to 2011 are used to illustrate the application of the model. Bayesian inference is used to conduct an importance analysis to assess the impact of the participants’ errors. Sensitivity analysis is then employed to gauge the effect the increased probability of occurrence of human errors on RCI. Finally, strategies for human error identification and mitigation of RCI are proposed. The identification of ability of maintainer in the case study as the most important factor influencing the probability of RCI implies the priority need to strengthen the maintenance management of the MTR system and that improving the inspection ability of the maintainer is likely to be an effective strategy for RCI risk mitigation.

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Cation chloride cotransporters (CCCs) are critical for controlling intracellular chloride homeostasis. The CCC family is composed of four isoforms of K-Cl cotransporters (KCC1-4), two isoforms of Na-K-2Cl cotransporters (NKCC1-2), one Na-Cl cotransporter (NCC) and two the structurally related proteins with unknown function, CCC8 also known as cation-chloride cotransporter interaction protein, CIP, and CCC9. KCC2 is a neuron-specific isoform, which plays a prominent role in controlling the intracellular Cl- concentration in neurons and is responsible for producing the negative shift of GABAA responses from depolarizing to hyperpolarizing during neuronal maturation. In the present studies we first used in situ hybridization to examine the developmental expression patterns of the cation-chloride cotransporters KCC1-4 and NKCC1. We found that they display complementary expression patterns during embryonic brain development. Most interestingly, KCC2 expression in the embryonic central nervous system strictly follows neuronal maturation. In vitro data obtained from primary and organotypic neuronal cultures support this finding and revealed a temporal correlation between the expression of KCC2 and synaptogenesis. We found that KCC2 is highly expressed in filopodia and mature spines as well as dendritic shaft and investigated the role of KCC2 in spine formation by analyzing KCC2-/- neurons in vitro. Our studies revealed that KCC2 is a key factor in the maturation of dendritic spines. Interestingly, the effect of KCC2 in spine formation is not due to Cl- transport activity, but mediated through the interaction between KCC2 C-terminal and intracellular protein associated with cytoskeleton. The interacting protein we found is protein 4.1N by immunoprecipitation. Our results indicate a structural role for KCC2 in the development of functional glutamatergic synapses and suggest KCC2 as a synchronizer for the functional development of glutamatergic and GABAergic synapses in neuronal network. Studies on the regulatory mechanisms of KCC2 expression during development and plasticity revealed that synaptic activity of both the glutamatergic and GABAergic system is not required for up-regulation of KCC2 during development, whereas in acute mature hippocampal slices which undergo continuous synchronous activity induced by the absence of Mg2+ solution, KCC2 mRNA and protein expression were down-regulated in CA1 pyramidal neurons subsequently leading to a reduced capacity for neuronal Cl- extrusion. This effect is mediated by endogenous BDNF-TrkB down-stream cascades involving both Shc/FRS-2 and PLCγ-CREB signaling. BDNF mediated changes in KCC2 expression indicate that KCC2 is significantly involved in the complex mechanisms of neuronal plasticity during development and pathophysiological conditions.

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Wild salmon stocks in the northern Baltic rivers became endangered in the second half of the 20th century, mainly due to recruitment overfishing. As a result, supplementary stocking was widely practised, and supplementation of the Tornionjoki salmon stock took place over a 25 year period until 2002. The stock has been closely monitored by electrofishing, smolt trapping, mark-recapture studies, catch samples and catch surveys. Background information on hatchery-reared stocked juveniles was also collected for this study. Bayesian statistics was applied to the data as this method offers the possibility of bringing prior information into the analysis and an advanced ability for incorporating uncertainty, and also provides probabilities for a multitude of hypotheses. Substantial divergences between reared and wild Tornionjoki salmon were identified in both demographic and phenological characteristics. The divergences tended to be larger the longer the duration spent in hatchery and the more favourable the hatchery conditions were for fast growth. Differences in environment likely induced most of the divergences, but selection of brood fish might have resulted in genotypic divergence in maturation age of reared salmon. Survival of stocked 1-year old juveniles to smolt varied from about 10% to about 25%. Stocking on the lower reach of the river seemed to decrease survival, and the negative effect of stocking volume on survival raises the concern of possible similar effects on the extant wild population. Post-smolt survival of wild Tornionjoki smolts was on average two times higher than that of smolts stocked as parr and 2.5 times higher than that of stocked smolts. Smolts of different groups showed synchronous variation and similar long-term survival trends. Both groups of reared salmon were more vulnerable to offshore driftnet and coastal trapnet fishing than wild salmon. Average survival from smolt to spawners of wild salmon was 2.8 times higher than that of salmon stocked as parr and 3.3 times higher than that of salmon stocked as smolts. Wild salmon and salmon stocked as parr were found to have similar lifetime survival rates, while stocked smolts have a lifetime survival rate over 4 times higher than the two other groups. If eggs are collected from the wild brood fish, stocking parr would therefore not be a sensible option. Stocking smolts instead would create a net benefit in terms of the number of spawners, but this strategy has serious drawbacks and risks associated with the larger phenotypic and demographic divergences from wild salmon. Supplementation was shown not to be the key factor behind the recovery of the Tornionjoki and other northern Baltic salmon stocks. Instead, a combination of restrictions in the sea fishery and simultaneous occurrence of favourable natural conditions for survival were the main reasons for the revival in the 1990 s. This study questions the effectiveness of supplementation as a conservation management tool. The benefits of supplementation seem at best limited. Relatively high occurrences of reared fish in catches may generate false optimism concerning the effects of supplementation. Supplementation may lead to genetic risks due to problems in brood fish collection and artificial rearing with relaxed natural selection and domestication. Appropriate management of fisheries is the main alternative to supplementation, without which all other efforts for long-term maintenance of a healthy fish resource fail.