Is bus bunching serious in Sydney? Preliminary findings based on Opal card data analysis


By Bobby Du & Paul-Antonin Dublanche


An efficient and reliable public transit system plays an important role in mitigation of congestion and attraction of more users from private car. However, sophisticated traffic condition and dynamic travel demand often make public transit services unstable and uncertain, which results in longer waiting time especially during peak hours or special events. One common phenomenon called bus bunching (BB) or platooning usually happens when the headway between successive buses arriving at the same bus stop is less than the scheduled headway or a certain threshold. BB is a major source of congestion, which not only causes passengers’ travel time delayed and extra waiting time, but also degrades the bus operation performance. Most of the prior researches on BB were limited in a single or multiple bus lines, consequently, only a few studies were found that focused on the whole bus network in a city or even larger region. Recent advances in big data create new opportunities for exploring BB problem in a large-scale scope.

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Overcrowded housing looms as a challenge for our cities


Shanaka Herath, SMART Infrastructure Facility at University of Wollongong and Rebecca Bentley, University of Melbourne

Overcrowding is an inevitable and often overlooked result of the affordable housing shortage in our cities.

When a dwelling requires four or more extra bedrooms to reasonably accommodate occupants, the standard commonly used in Australia defines that as severe overcrowding. In 2011, 41,390 Australians lived in severely overcrowded dwellings, an increase of one-third from 2006. This increase occurred mostly in cities where house prices had risen sharply.

Our recent research, to be published soon, examined where overcrowded housing is located in our capital cities. We found:

  • Sydney and Melbourne are most affected by concentrated overcrowding
  • levels of overcrowding are highest in middle-city areas (except in Adelaide)
  • overcrowding overlaps strongly with socioeconomic disadvantage. Continue reading

Infrastructure Resilience: Planning for Future Extreme Events

By Sarah Dunn

Natural hazards have the potential to cause large-scale impacts and disruption to all countries and if these events occur in highly populated areas the impacts can be catastrophic.  This has been shown by previous earthquake events in Christchurch and Haiti and by hurricanes Katrina and Sandy.  The severity and lasting impact of these hazards are often linked to the resilience of critical infrastructure systems (including: water distribution networks, electrical systems and transportation networks) which underpin our communities and support social and economic development.  These systems are currently being subjected to a multitude of challenges – from a changing climate, to increasing population demands and economic austerity.  Therefore, we need new approaches to assess and manage the resilience of these critical systems.

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Human behaviour modelling and simulation for crisis management

By Carole Adam

The SWIFT project (funded by University Grenoble-Alps) investigates the somewhat irrational behaviour of citizens confronted with wildfire risk in Victoria. It relies on survey data from the Bushfire Research Commission created after the Black Saturday fires in 2009, to design a realistic model of this behaviour. An initial model focused on the mismatch between objective and subjective values of both the level of risk and the individual ability to face it; it proved valid against behaviour statistics, and also showed good explicative power despite its apparent simplicity, at the level of the global population. This model was also used to investigate the effects of different communication strategies.

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No more cars! – The Post-car Ile-de-France project

By Arnaud Banos

The Post-car Ile-de-France project (funded by Mobile Lives Forum, SNCF) investigates the hypothesis of an abrupt transition towards lifestyles that depend less on the use of personal vehicles. Its main goal is to explore with people the possible impacts of this scenario on their lifestyles and on the way we should design cities and territories. In such perspective, a serious game prototype has been developed, allowing gamers to interact with a virtual simplified urban environment, in order to explore the possible impacts of a drastic limitation of the use of personal vehicles on urban life. That first step has a very precise purpose: opening up people’s mind by letting them face – in a friendly and intuitive way led by personal experimentation – the multiple constraints they would face as urban actors in such situation. Building this shared common baseline is crucial in the perspective of engaging public participation of citizens, planners and deciders.

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On gardens and gardening

By Graham HarrisGraham Harris v3

“We must take care of our garden” Voltaire in “Candide” (1759)

While gardening has become incredibly popular in many countries in recent years; and everything from garden centres to visiting and restoring historical gardens have become big business [1], gardeners are not it seems a deeply reflective and philosophical lot. There are many excellent texts on garden design and the way it has changed over time on various continents [2], and while the literature on gardening and garden design is vast, the literature on the philosophy of gardens is rather small. Do we think deeply enough about what we are doing? Some do [3], but not that many.
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Complementarity, flat Earths and alternative facts

By Graham HarrisGraham Harris v3

Just a week after I wrote my last blog about unsupervised learning, cognitive science and Andy Clark’s “predictive processing” an article appears in the New Scientist magazine entitled “Reality? It’s what you make it” [i].

This piece, by Philip Ball, discusses some very new ideas in quantum theory that go under the general title of participatory realism [ii]. This new concept, championed by Christopher Fuchs, Markus Müller and others, argues that the world, as we experience it from a first person perspective, is the emergent property arising from something much deeper, more complex and mysterious than we can imagine. On his web site Müller asks “Can we have a fully information-theoretic approach to physics in which not a notion of “external world”, but of “observation” is the fundamental starting point?” [iii]. It seems we can.

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An unsupervised life

By Graham HarrisGraham Harris v3

In this blog I want to pull some threads together that I have written about previously and I will to try to make some bigger-picture connections. I am going to link cybernetics to embodiment and unsupervised learning in living systems.

Once we make the philosophical step of moving from 1st order cybernetics (rationalist and naïve realist science) to 2nd order cybernetics (with the observer in the loop) then we start down a path with significant consequences. Not, I might add, a complete move away from science (to head off the immediate scientific criticisms of subjectivity and muddled thinking).
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The challenge of embodiment

By Graham HarrisGraham Harris v3

Regular readers of this blog will remember that I have long argued for a middle way – too often in the history of ideas we end up in polarising debates around extreme positions. One pertinent debate is that between philosophical realists (who believe that reality exists independently of observers) and idealists (who think that reality is mentally constructed). So is there a middle way here also – an “entre deux” between the Scylla of realism and the Charybdis of idealism? Well, yes there is, and it arises out of ideas developed around the problem of complexity, reflexivity and 2nd order cybernetics.
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Thinking Systems Redux

By Graham HarrisGraham Harris v3

After an enforced layoff from writing, the Thinking Systems blog series is about to be reborn. What was once an attempt to understand complexity from a rationalist perspective has now become part of a much larger initiative. The previous focus on trying to make complexity “manageable” is understandable; I was a scientist once after all. My enforced layoff has caused me to reflect more deeply and broadly on what makes us human and on just how “unmanageable” many aspects of life really are. Too great a focus on prediction and strategy can leave us unprepared for the unexpected; too great a reliance on reason leaves us emotionally bereft and unwilling to accept change in the face of crisis.
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