Do wind vent holes in banners make a difference? We used a wind tunnel to find out

Do the holes in the banner carried by these Vietnam veterans during an Anzac Day parade in Canberra make any difference?

Do the holes in the banner carried by these Vietnam veterans during an Anzac Day parade in Canberra make any difference? AAP Image/Alan Porritt

Matthew Mason, The University of Queensland and Jonathan Roberts, Queensland University of Technology

The next time you see a banner hung across a street or from a bridge, or hoisted as part of a street march, protest or demonstration, take a closer look. You may see that the banner has holes or slits cut into it.

But why would someone cut holes into a perfectly good banner?

These are so-called “wind vents”, and for some reason people have been mutilating their banners with these holes in the belief that their presence will significantly reduce the wind loading on the banner.

But does a banner with holes or slits really have an easier time in the wind than an equivalent banner that is hole free?

History and legislation

It is not known when people started to cut holes into their banners. There is very little written about the practice, and much of the knowledge appears to come via word of mouth or has been transferred from other wind related domains.

What is obvious from the websites of the world’s sign and banner makers is that they are frustrated with having to cut holes into their lovingly-made creations.

Some banner makers simply refuse, and tell their customers that if they want holes, then they can cut them themselves.

The apparent importance of banner wind vents has led some local governments around the world to make them mandatory for banners installed in certain locations. No vent holes, no banner allowed!

The regulations of the Brisbane City Council, in Queensland, Australia, state that for banners to be installed on the city’s iconic Story Bridge, they “must be provided with wind vent holes” and that “wind holes (vents) need to be spaced at approx. 3m intervals”.

Brisbane City Council’s Story Bridge banner design guide indicating location of ‘wind vent holes’.
Brisbane City Council design guide

The small town of Springville, Utah, USA, states in its regulations that at least 20% of the area of the banner must be made up of holes. It suggests “half moon shaped vents 4-6 inches wide and facing down throughout the banner”.

Understanding the aerodynamics

To understand what, if anything, wind vents do for our banners, we need to visit the work of aerodynamics specialists.

In 1956, B. G. de Bray, an aerodynamics expert at the UK’s Royal Aircraft Establishment, performed a series of wind tunnel tests to show how flat plates with holes in them performed in a moving air stream. He was interested in how plates could be used for airbrakes on aircraft as they land.

His experiments showed that perforations (holes) make the air flow more stable but that there was “only a comparatively small reduction in drag coefficient”. He shows a graph recording the relationship between the area of the holes and the change in drag coefficient of a flat plate. The graph indicates that making 20% of a banner’s area holes will reduce the drag by around 5% in a wind of 150km/h.

These figures are taken from de Bray’s 1956 work on wind tunnel testing of flat plates with holes and how drag relates to hole area in a 150km/h wind. Note that CD designates the drag coefficient, which is a normalised way of representing force that accounts for plate size (or in our case the banner) and wind speed. Doing this allows the wind tunnel data to be scaled to full-size.

When we consider de Bray’s other finding – that holes do make the air flow more stable – we can look at a common example of this in action in round parachutes.

Billowing structures that fill with air on the windward side, such as round parachutes, become unstable when there are no holes in the structure. The air tends to spill almost randomly from the structure’s edge. This makes the structure flap around in the wind in a seemingly random manner.

This was discovered in the early days of parachute development. In the late 1700s, a number of parachute developers were killed due to accidents relating to their unstable and oscillating chutes.

In 1804, Frenchman Joseph Lelandes invented the apex vent, a hole in the top of the parachute. This appeared to solve the problem of stability but did not appear to reduce the drag, ideal for parachuting where you need the drag.

Since then there have been many studies showing the benefits of holes in round parachutes. One group even found during their experiments that vent holes in round parachutes slightly increase the drag on the chute while making it more stable.

Wind tunnel tests

Following in de Bray’s footsteps, we decided to turn to wind tunnel experiments to assess just how much impact those holes had on wind forces.

We conducted a series of simple experiments where we put scaled versions of banners in a wind tunnel and measured the wind forces. We did this for a range of wind speeds and number of vents (holes). We then measured how the forces changed from test to test.

We performed experiments where vents were rectangular holes cut in the fabric and others where the vents were rectangular holes cut on three sides and allowed to hinge at the top (flaps).

A test banner with 7% of its area made of holes in the wind tunnel.
Author supplied
As for above, but showing a banner with 7% porosity and hinged flaps.
Author supplied

Experimental wind speeds tested ranged from approximately 25km/h to 100km/h and the range of vent hole area to total banner area ratios (porosity) assessed was from zero (no holes in the banner) to approximately 20%, which coincides with the Springville regulations and makes a pretty holy banner.

A plot showing drag on the banner versus porosity of the banner for the 100km/h tests over the range of banner porosities. The vertical axis shows the drag coefficient (CD) ratio, which is the wind force measured on the porous banner divided by the wind force on the solid banner. A porosity of 0.1 is 10% holes/vents/flaps.
Author supplied

A value of 1 in the figure (above) would indicate that the vents have done nothing and a value of 0.9 would suggest there has been a 10% reduction in load.

It is clear that wind vents do reduce the wind load on a banner, but as de Bray showed, the reduction in load is relatively small until porosity becomes large.

The reduction in drag force is greater for holes and hinged flaps than found by de Bray (and others) for uniformly perforated plates or fabrics.

The wind speed makes a difference. At low wind speeds the presence of vents can actually increase the wind load on a banner, which in our test was found to be up to 5%.

In general though, force coefficients decreased as wind speeds increase. This was particularly the case for the banners with flaps, where these vents became more open as the wind speed increased.

So the type of vent makes a big difference. Banners with holes rather than hinged flaps experienced lower wind loads. Both of these vent types experience lower loads than on uniformly perforated plates, which perform similarly to porous mesh fabrics.

With these points in mind, we return to the Brisbane City Council’s regulations for placing banners on the Storey Bridge. It is now possible to calculate the effect of their prescribed wind vents.

If we assume that they would like holes, and the maximum size of a banner is 18m wide by 0.9m high, then our best guess estimate is a semi-circular hole radius of 25cm noting also that five wind holes are required. We calculate that at most, 3% of the banner will be holes.

Interpolating our figure this would give us a 2% reduction in wind load. A sign of 98% the area of the maximum would be 18m wide and 0.88m high and would only require you to trim 2cm off the bottom of the sign to create a sign of equivalent drag to the one with five holes in it! It hardly seems worth the effort.

The verdict

The science shows us that flat structures behave one way, and billowing air-filled structures behave a different way. It seems that our legislators have been confused and applied results from parachutes to flat banners.

If you have a banner tied in such a way that it will remain relatively flat in the wind, then it seems that the benefits of putting in vents are minimal unless you make your banner into Swiss cheese.

You are simply better off making a slightly small banner to achieve the same reduction in load.

The Conversation

Matthew Mason, Lecturer in Civil Engineering, The University of Queensland and Jonathan Roberts, Professor in Robotics, Queensland University of Technology

This article was originally published on The Conversation. Read the original article.

Australia’s first robotic help in a hip replacement operation

The surgeon and the robotic arm will work together on a hip replacement.

The surgeon and the robotic arm will work together on a hip replacement. Stryker, Author provided

Ross Crawford, Queensland University of Technology; Anjali Jaiprakash, Queensland University of Technology, and Jonathan Roberts, Queensland University of Technology

The first robotically assisted hip replacement operation in Australia is due to be performed today on a patient in Brisbane.

A total hip replacement (THR) is one of the most successful operations that surgeons perform, with more than 43,000 carried out last year in Australia alone.

The robot technology to help in such operations has been used for some years in the US but has only recently reached Australia.

But if the operations are so popular and successful, why let a robot in on the surgery?

The hip opp

A hip replacement involves an incision to expose the hip joint and the placement of an acetabular component (the cup) and a femoral component (the stem). A head is then placed on the stem and a ball and socket joint is created that is the patient’s new hip.

A typical ball and socket artificial hip replacement.
Ross Crawford, Author provided

Though very successful, the operation can be quite challenging to perform in certain patients such as the very overweight and those with complex deformities due to childhood diseases or trauma. There is also a learning process for the surgeon in performing a hip replacement and it is hoped this can be shortened by using robotic technology.

Accurate positioning of the components of a hip replacement is important. Having the cup and stem in the correct position can decrease the chance of complications such as dislocation, where the head comes out of the cup. Making sure the joint stem is located in a way to ensure optimal leg length may also lead to improved function of the new hip.

Currently, surgeons rely on their experience and judgement to correctly place the components of a hip replacement. Many studies have shown that even experienced surgeons can have difficulty in reliably and accurately placing the cup in the correct orientation. They sometimes find placement of the stem challenging too.

This is where a robot can help.

The robot surgeon

Up until now, the Australian experience of robotic orthopaedic surgery has been limited to partial knee replacements. The first was carried out in April last year, and since then more than 280 of these procedures have been performed.

The first robotically assisted total hip replacement operation will take place today at Brisbane’s Holy Spirit Northside Hospital, and it’s likely such procedures will quickly become just as popular as the knee operations.

The Stryker Mako advanced robotic arm that helps with the surgery.
Stryker, Author provided

So what is different with a robotic total hip replacement and where does the robot help?

The MAKO robotic system is a carefully controlled robotic arm that aids surgeons in placement of the components of a total hip replacement. It makes the operation more accurate and safer for surgeons, regardless of their experience.

The main difference from a patient’s point of view is that a pre-operative CT scan is needed to plan the procedure. Traditionally, surgeon relied purely on an X-ray to plan a total hip replacement.

When performed by a robot, planning for the procedure is done by specialist engineers in collaboration with the surgeon. The engineer and surgeon work together to determine the optimal position for the components and they create a plan.

The plan places the cup in the correct orientation to match the patient’s anatomy and the stem is also sized to fit the patient’s femur. The aim is to accurately restore the patient’s hip anatomy, particularly leg length.

Once the surgery begins, the surgeon exposes the hip joint in the usual way. Trackers are placed on the pelvis and on the femur allowing the robot to register these bones.

The trackers are attached to the bones using small posts with a screw thread on the tip. A series of points on the patient’s pelvis and femur are then registered and the robot creates a 3D representation that matches the CT scan.

Once the robot understands the geometry, it is able to follow any movement of the patient by the signal transmitted by the trackers fixed to the bones.

A cutting tool called reamer – somewhat like a powered round cheese grater – is attached to the robot and is used to prepare the bone to accept the cup. The surgeon holds the reamer but the robot constrains it and will not let the surgeon remove bone beyond the planned amount.

This will prevent any accidental damage to the bone and make sure the reaming can only occur as planned. Human error is removed from the preparation.

After reaming is finished, the cup is grasped by the robot and the robot sets the correct positioning. The surgeon then hammers the cup into the correct position in the pelvis.

They are able to monitor the position of the implant on the computer screen as it is “seated”. The cup cannot be driven in too far, as the robot constrains where the cup can be placed, as with the reamer.

Next the surgeon places a broach in the femur to prepare a cavity for the femoral component (stem). The broach can be tracked by the robot to make sure it is placed in the correct orientation and the patient’s legs are at the planned length.

Once happy, the surgeon cements the stem into where the broach was positioned, places a head on the femur and puts the head into the cup.

Who’s in charge?

Though the robot is constraining the surgeon to execute the plan, the surgeon remains in charge at all times. The surgeon continues to carry all responsibility for the success of the operation and any complications.

This first step of robotically assisted total hip replacement is relatively easy. The robotic technology (robotics, navigation and haptics) being used is very mature.

But as we are seeing in many industries, the capability of robotics is expanding rapidly. It will not be long before the technology is advanced enough to take over far more of the operation from the human surgeon.

Then the big ethical questions will arise. Even now orthopaedic robots are being limited in what they can do because the step to autonomous surgery is currently a step too far.

Like driverless cars, the questions of liability and trust continue to be aired when discussing robotic-surgery or health care.

But also like driverless cars, robotic surgeons do not have to be perfect. They just have to be better than humans.

The Conversation

Ross Crawford, Professor of Orthopaedic Research, Queensland University of Technology; Anjali Jaiprakash, Post-Doctoral Research Fellow, Medical Robotics, Queensland University of Technology, and Jonathan Roberts, Professor in Robotics, Queensland University of Technology

This article was originally published on The Conversation. Read the original article.

New relaxed drone regulations will help the industry take off

CASA makes it easier for low risk flying of drones. Flickr/Richard Thorek, CC BY-NC-SA

Reece Clothier, RMIT University and Jonathan Roberts, Queensland University of Technology

The Australian drone industry is set for a shake up following the announcement of a long-awaited relaxation of regulations on their operation.

Australia’s Civil Aviation Safety Authority (CASA) says the amended regulations will come into effect in late September 2016, and with them comes the introduction of new categories of what are known as remotely piloted aircraft systems (RPAS).

The regulations define new low-risk commercial RPAS operations, which will allow operators of sub-2kg craft to fly without the need for an approval or licence.

A drone must be operated in daytime and within visual line of sight of the remote pilot to be classified as low risk. It must not be flown over populous areas and must be kept at least 30 metres from other people.

The drone cannot be flown greater than 130m above ground and it must not be flown within 5.5km of a controlled airport.

Commercial operators in this new category will have to register their operations with CASA on a yet-to-be live website.

Relaxed regulations will also apply to private owners of RPAS of up to 150kg. This is provided they only fly their drone over their private property and they do not operate their aircraft for direct commercial reward.

Why the change?

In 2002, CASA was the first in the world to regulate the operation of drones.

The regulations, contained in Part 101 of the Civil Aviation Safety Regulation (CASR 1998), were long considered ground breaking. Much of the success of the Australian unmanned aircraft industry is owed to the flexible approach outlined in the regulations.

In 2007, there were fewer than 25 certified drone operators in Australia. By March 30, 2016, this number had grown to 500, with most operating small multi-rotor RPAS.

But with this rapid growth came the increasing need for regulatory reform. CASA recognised that the regulations needed to keep pace with increasingly capable technology, and the changing operational needs of the sector.

It also realised that processing an ever increasing number of regulatory applications was not sustainable.

Welcome news

The new changes will significantly reshape the drone industry.

Operators already licensed by CASA are expected to face increased competition from the new sub-2kg RPAS operators. These new operators will be able to provide equivalent aerial photography and inspection services without the same regulatory overhead.

Similarly, there will be an increase in the number of end-users choosing to own and operate their own internal RPAS capability instead of contracting existing RPAS service providers. Examples include the use of small inspection drones on building sites and the use of drones by tactical police units to assist them in hostage situations.

But it is not all doom and gloom for the current licensed RPAS operators. The standard operating conditions applicable to the new low-risk categories are restrictive.

Larger and more reliable drones will still be needed to carry bulky and more expensive payloads such as laser scanners, and hyper-spectral and cinema-quality cameras. These drones will still need to be operated by licensed operators.

Approval is still required for first person view (FPV) outdoor flying operations, where the remote pilot flies by means of a camera mounted on board the drone.

Similarly, autonomous drones, which operate without any input from a pilot, also require CASA approval on a case-by-case basis.

A large drone that will still require licensed operators for commercial use.
Stefan Hrabar/CSIRO/UAV Challenge

Research and educational institutions, such as universities, are also expected to benefit from the new categories, provided they operate their aircraft over their own property and in accordance with all other operational restrictions.

Previously, these institutions were subject to the same licensing requirements as commercial operators.

Hobby users

The amended regulations do not address concerns posed by the rapidly growing number of hobby drone users.

Regulations applicable to hobby or recreational users are contained in CASR 1998 Part 101.G, which is the subject of a separate CASA regulatory reform project.

There is growing concern over the risks hobby users pose to other aircraft and to members of the public. Some of these hobby users are not aware of the potential danger their drone may pose.

There have been numerous near misses of small drones with passenger aircraft in recent years. As the rate of these incidents increases, there is real concern that a drone will eventually be ingested into an aircraft engine causing catastrophic damage – or worse, an airline crash.

Others are well aware of the dangers their drones may pose to the public but they are deliberately mischievous anyway.

Education remains the only effective tool, with CASA leading a campaign to educate hobby users on the safe operation of their aircraft and the regulations that apply to them.

Without doubt, the release of the amended regulations will mark a significant milestone in the history of the Australian drone industry. They will help to sustain the safe and viable growth of the sector.

But the devil may still lie in the detail, of course, with the accompanying manual of standards yet to be released by CASA. The manual will contain more detailed requirements including those for remote pilot licences, flights in controlled airspace, and flights beyond visual line of sight of the pilot.

CASA’s exact interpretation of “Aerial Work” and “Commercial Reward” also remain unclear.

The Conversation

Reece Clothier, Senior Lecturer, RMIT University and Jonathan Roberts, Professor in Robotics, Queensland University of Technology

This article was originally published on The Conversation. Read the original article.

Digital diagnosis: intelligent machines do a better job than humans

It takes time for a human to become good at diagnosing ailments, but that learning is lost when they retire. Shutterstock/Poproskiy Alexey

Ross Crawford, Queensland University of Technology; Anjali Jaiprakash, Queensland University of Technology, and Jonathan Roberts, Queensland University of Technology

Until now, medicine has been a prestigious and often extremely lucrative career choice. But in the near future, will we need as many doctors as we have now? Are we going to see significant medical unemployment in the coming decade?

Dr Saxon Smith, president of the Australian Medical Association NSW branch, said in a report late last year that the most common concerns he hears from doctors-in-training and medical students are, “what is the future of medicine?” and “will I have a job?”. The answers, he said, continue to elude him.

As Australian, British and American universities continue to graduate increasing numbers of medical students, the obvious question is where will these new doctors work in the future?

Will there be an expanded role for medical professionals due to our ageing populations? Or is pressure to reduce costs while improving outcomes likely to force the adoption of new technology, which will then likely erode the number of roles currently performed by doctors?

Driving down the costs

All governments, patients and doctors around the world know that healthcare costs will need to reduce if we are to treat more people. Some propose making patients pay more, but however we pay for it, it’s clear that driving the cost down is what needs to happen.

The use of medical robots to assist human surgeons is becoming more widespread but, so far, they are being used to try and improve patient outcomes and not to reduce the cost of surgery. Cost savings may come later when this robotic technology matures.

It is in the area of medical diagnostics where many people see possible significant cost reduction while improving accuracy by using technology instead of human doctors.

It is already common for blood tests and genetic testing (genomics) to be carried out automatically and very cost effectively by machines. They analyse the blood specimen and automatically produce a report.

The tests can be as simple as a haemoglobin level (blood count) through to tests of diabetes such as insulin or glucose levels. They can also be used for far more complicated tests such as looking at a person’s genetic makeup.

A good example is Thyrocare Technologies Ltd in Mumbai, India, where more than 100,000 diagnostic tests from around the country are done every evening, and the reports delivered within 24 hours of blood being taken from a patient.

Machines vs humans

If machines can read blood tests, what else can they do? Though many doctors will not like this thought, any test that requires pattern recognition will ultimately be done better by a machine than a human.

Many diseases need a pathological diagnosis, where a doctor looks at a sample of blood or tissue, to establish the exact disease: a blood test to diagnose an infection, a skin biopsy to determine if a lesion is a cancer or not and a tissue sample taken by a surgeon looking to make a diagnosis.

All of these examples, and in fact all pathological diagnoses are made by a doctor using pattern recognition to determine the diagnosis.

Artificial intelligence techniques using deep neural networks, which are a type of machine learning, can be used to train these diagnostic machines. Machines learn fast and we are not talking about a single machine, but a network of machines linked globally via the internet, using their pooled data to continue to improve.

It will not happen overnight – it will take some time to learn – but once trained the machine will only continue to get better. With time, an appropriately trained machine will be superior at pattern recognition than any human could ever be.

Pathology is now a matter of multi-million dollar laboratories relying on economies of scale. It takes around 15 years from leaving high school to train a pathologist to function independently. It probably takes another 15 years for the pathologist to be as good as they will ever be.

Some years after that, they will retire and all that knowledge and experience is lost. Surely, it would be better if that knowledge could be captured and used by future generations? A robotic pathologist would be able to do just that.

Radiology, X-rays and beyond

Radiological tests account for over AUS$2 billion of the annual Medicare spend. In a 2013 report, it was estimated that in the 2014-15 period, 33,600,000 radiological investigations would be performed in Australia. A radiologist would have to study every one of these and write a report.

Radiologists are already reading, on average, more than seven times the number of studies per day than they were five years ago. These reports, like those written by pathologists, are based on pattern recognition.

Currently, many radiological tests performed in Australia are being read by radiologists in other countries, such as the UK. Rather than having an expert in Australia get out of bed at 3am to read a brain scan of an injured patient, the image can be digitally sent to a doctor in any appropriate time zone and be reported on almost instantly.

What if machines were taught to read X-rays working at first with, and ultimately instead of, human radiologists? Would we still need human radiologists? Probably. Improved imaging, such as MRI and CT scans, will allow radiologists to perform some procedures that surgeons now undertake.

The field of diagnostic radiology is rapidly expanding. In this field, radiologists are able to diagnose and treat conditions such as bleeding blood vessels. This is done using minimally invasive techniques, passing wires through larger vessels to reach the point of bleeding.

So the radiologists may end up doing procedures that are currently done by vascular and cardiac surgeons. The increased use of robotic assisted surgery will mean this is more likely than not.

There is a lot more to diagnosing a skin lesion, rash or growth than simply looking at it. But much of the diagnosis is based on the dermatologist recognising the lesion (again, pattern recognition).

If the diagnosis remains unclear then some tissue (a biopsy) is sent to the laboratory for a pathological diagnosis. We have already established that a machine can read the latter. The same principle applies to the recognition of the skin lesion.

Once recognised and learnt, the lesion will be able to be recognised again. Mobile phones with high-quality cameras will be able to link to a global database that will, like any other database with learning capability, continue to improve.

It’s not if, but when

These changes will not happen overnight, but they are inevitable. Though many doctors will see these changes as a threat, the chance for global good is unprecedented.

An X-ray taken in equatorial Africa could be read with the same reliability as one taken in an Australian centre of excellence. An infectious rash could be uploaded to a phone and the diagnosis given instantly. Many lives will be saved and the cost of health care to the world’s poor can be minimal and, in many cases, free.

For this to become a reality, it will take experts to work with machines and help them learn. Initially, the machines may be asked to do more straightforward tests but gradually they will be taught, just as humans learn most things in life.

The medical profession should grasp these opportunities for change, and our future young doctors should think carefully where the medical jobs of the future will lie. It is almost certain that the medical employment landscape in 15 years will not look like the one we see today.

The Conversation

Ross Crawford, Professor of Orthopaedic Research, Queensland University of Technology; Anjali Jaiprakash, Post-Doctoral Research Fellow, Medical Robotics, Queensland University of Technology, and Jonathan Roberts, Professor in Robotics, Queensland University of Technology

This article was originally published on The Conversation. Read the original article.

A fine balance: saving Australia’s unique wildlife in a contested land

A golden-tailed gecko – one of the inhabitants of the Brigalow Belt. Eric Vanderduys, Author provided.

Rocio Ponce-Reyes, CSIRO; Danial Stratford, CSIRO; Iadine Chadès, CSIRO; Jennifer Firn, Queensland University of Technology; Josie Carwardine, CSIRO; Sam Nicol, CSIRO; Stuart Whitten, CSIRO, and Tara Martin, CSIRO

The Brigalow Belt in Queensland is a national hotspot for wildlife, especially for birds and reptiles. Many of these, such as the black-throated finch, golden-tailed gecko and brigalow scaly-foot are found nowhere else in the world.

But the region is also one of the most transformed and contested areas in Australia. People want to use the Brigalow for many different things: conservation, grazing, agricultural production, mineral and gas extraction. This region also overlaps with the country’s largest reserves of coal and coal seam gas.

Together, the economic activities in the region bring land clearing, changes to water sources, invasion of exotic species and changed fire patterns, which threaten the region’s unique biodiversity.

Currently, at least 179 species of plants and animals are known to be threatened in the region. In research published today we look at the best way to conserve these species, attempting to balance the competing uses of this region.

The Brigalow Belt in Queensland.

Meet the locals

The Brigalow Belt bioregion takes its name from the Aboriginal word “brigalow” that describes the region’s dominant tree species (Acacia harpophylla). Brigalow trees can grow up to 25 metres in height and are characterised by their silver foliage.

Brigalow trees – a relative of the golden wattle, Australia’s national floral emblem.
Rocio Ponce-Reyes, Author provided

Brigalow ecosystems once formed extensive open-forest woodlands that covered 30% of the region, but since the mid-19th century about 95% of their original extent has been cleared, mostly for farming. The remaining 600,000 hectares of relatively small, isolated and fragmented remnants of brigalow forest are now protected as an endangered ecological community. The Semi-Evergreen Vine Thicket, or bottle tree scrub, is also listed.

Mammals are the most threatened group of the region. Eight species are already extinct, some of them locally (such as the eastern quoll and northern bettong) and others globally (such as the Darling Downs hopping mouse).

Other iconic mammals in the region include the bridled nail-tail wallaby and the northern hairy-nosed wombat. Both are listed as endangered at federal and state levels.

Long history of transformation

Traditional owners managed the region, including through burning practices, until the arrival of the first European settlers in the 1840s. Since then, management practices have changed markedly, especially with the establishment of the Brigalow and Other Lands Development Scheme in the 1950s.

This scheme provided new settlers, including many soldiers returning from the second world war, with infrastructure, financial assistance and a block of bushland. In return, they were expected to clear their land and establish a farm within 15 years to support the growing Queensland population.

Since then, the rate of clearing of Brigalow has varied in response to changes in legislation through time.

The black-throated finches of the Brigalow are regarded as endangered.
Eric Vanderduys, Author provided

The Brigalow’s silver lining

There are many ways of dealing with the threats facing the Brigalow’s biodiversity. But which gives us the most bang for our buck?

We worked with 40 key stakeholders from the region to answer this question.

You might think there’s a simple answer: stop development. However, native plants and animals in the Brigalow region are threatened by an accumulation of past, current and future land uses, and all need to be addressed to save these species.

Stakeholders focused on the strategies they believed to be the most feasible and achievable for minimising negative impacts and managing threats arising from all land uses in the region. The strategies, listed below, target several threats posed by industries in the region, such as agriculture, grazing, coal mining and coal seam gas.

  1. Protect remnant vegetation
  2. Protect important regrowth vegetation
  3. Establish key biodiversity areas, such as identify and manage areas of critical habitat
  4. Restore key habitats
  5. Manage pest animals such as feral cats, pigs and noisy miners
  6. Manage invasive plants
  7. Manage fire
  8. Manage grazing
  9. Manage water
  10. Manage pollution
  11. Build a common vision

The stakeholders included a strategy to “build a common vision” because they saw this as vital to achieving the other strategies. This common vision would be built by stakeholders to identify shared goals that balance environmental, social and economic considerations, such as the extent and nature of future developments.

Not a snake, but a legless lizard: the Brigalow scaly foot.
Eric Vanderduys, Author provided

We discovered that managing fire and invasive plant species would provide the best bang for our buck in terms of protecting the Brigalow Belt’s threatened plants and animals. Protecting remaining stands of vegetation offered high benefits to native wildlife, but came at high economic costs. We also discovered that building a common vision will improve the effectiveness of the other management strategies.

Experts estimated that it would cost about A$57.5 million each year to implement all 11 proposed management strategies in the Brigalow Belt. This is around A$1.60 per hectare each year.

If we don’t make this investment, it’s likely 21 species will disappear from the region over the next 50 years. But if we implement the 11 strategies, 12 of these species will likely survive (including the regent honeyeater, northern quoll and bridled nail-tail wallaby) and the outlook of many other species will improve. Species-specific recovery plans may help stop the other nine species (such as the northern-hairy nosed wombat and the swift parrot) from being lost from the region.

When it comes to saving species, working together with a common vision to balance the needs of wildlife and people will deliver the best outcomes in this contested region.

The Conversation

Rocio Ponce-Reyes, Postdoctoral Research Fellow, CSIRO; Danial Stratford, Senior experimental scientist, CSIRO; Iadine Chadès, Senior research scientist, CSIRO; Jennifer Firn, Associate professor, Queensland University of Technology; Josie Carwardine, Research Scientist, Ecosystem Sciences, CSIRO; Sam Nicol, Postdoctoral Researcher, Ecosystem Sciences, CSIRO; Stuart Whitten, Group Leader, Economics and Future Pathways, CSIRO, and Tara Martin, Principal Research Scientist, CSIRO

This article was originally published on The Conversation. Read the original article.

An Uber for apartments could solve some common housing problems

Bringing together buyers and sellers of apartments could result in better apartment pricing and design. CucombreLibre/Flickr, CC BY

Andrea Sharam, Swinburne University of Technology and Lyndall Bryant, Queensland University of Technology

Speculative property developers, criticised for building dog boxes and the slums of tomorrow, are generally hated by urban planners and the public alike. But the doors of state governments are seemingly always open to developers and their lobbyists.

Politicians find it hard to say no to the demands of the development industry for concessions because of the contribution housing construction makes to the economic bottom line and because there is a need for well located housing. New supply is also seen as a solution to declining housing affordability.

Classical economic theory however is too simplistic for housing supply. Instead, an offshoot of Game Theory – Market Design – not only offers greater insight into apartment supply but also can simultaneously address price, design and quality issues.

New research reveals the most significant risk in residential development is settlement risk – when buyers fail to proceed with their purchase despite there being a pre-sale contract. At the point of settlement, the developer has expended all the project funds only to see forecast revenue evaporate. While new buyers may be found, this process is likely to strip the profitability out of the project. As the global financial crisis exposed, buyers are inclined to walk if property values slide.

This settlement problem reflects a poor legal mechanism (the pre-sale contract), and a lack of incentive for truthfulness. A second problem is the search costs of finding buyers. At around 10% of project costs, pre-sales are more expensive to developers than finance. This is where Market Design comes in.

Matching buyers and sellers

Market Design argues individuals will cooperate where there is an advantage in doing so. This is the premise of the “sharing economy”. Much of the innovation in the sharing economy also reflects another insight of Market Design; that markets can be constructed in different ways to serve different purposes.

Our interest here is in two-sided matching markets, which is a common design for e-commerce. Buyers are aggregated on one side of the market and sellers on the other with a market manager. Think Airbnb or Uber. Aggregating potential buyers of apartments would resolve the issue of searching for presales: taking the process from looking for needles in the haystack to shooting fish in a barrel.

Both buyers and developers would need to be registered participants, and the market manager would be responsible for recruiting participants and matching development opportunities to buyers. Pre-identification of buyers would avoid much of the cost of pre-sales and search time.

In addition there could be real-time communication and customer segmentation that permitted developers to take account of the actual expressed preferences of the buyers. An expanded apartment product range and cost reduction should make apartments more attractive to owner-occupiers, reducing settlement risk. The same can be said of having more owner-occupiers and fewer investors.

Pre-sales are one of the most expensive and riskiest elements of property development.
Dean Lewins/AAP

Keeping developers honest

However, as one financier (who agreed to be interviewed but not identified) rightly noted, developers can be expected to pocket the savings. Residential development is oligopolistic so there needs to be a source of competition to put pressure on prices, and who better than consumers themselves?

DIY apartment developers, what we call “deliberative” developers, now comprise 10% of all new housing in Berlin, and it has taken off in Europe. Deliberative developers make cost savings in the order or 25-30% and get the type and high quality product they want. Financing constraints have meant deliberative development in Australia has been the preserve of the well heeled, but support from impact investors for example, would enable ordinary households access to such self-help schemes.

One further change however is required. Planning schemes need to impose density restrictions (in the form of height limits, floor space ratios or bedroom quotas) in urban localities where housing demand and land values are high in order to dampen speculation and de-risk development by creating certainty.

Building a model that encourages owner-occupiers

The existing development model relies on capturing uplift in site value, and suits investors (incentivised by tax concessions) seeking rental yields in the short term and capital gains in the longer term. The price of land in the vicinity of redevelopment sites is then pushed up as landholders’ expectation of future yield is raised. It is a vicious circle in which developers seek to compensate for these higher prices through increased dwelling yields, smaller apartments and reduced amenity, further alienating would be owner-occupiers from the market.

However restrictions on over-development of larger infill sites needs to be offset by permitting intensification of “greyfield” suburbs. Aggregating existing housing lots to enable precinct regeneration, and moderate height and density increases would permit better use of airspace, delivering housing designs that can optimise land use while retaining amenity.

Redesigning the market and supporting deliberative development are the keys to achieving good, affordable apartments.

The Conversation

Andrea Sharam, Research Fellow housing & homelessness, Swinburne University of Technology and Lyndall Bryant, Lecturer in Property Economics, Queensland University of Technology

This article was originally published on The Conversation. Read the original article.

Self-driving cars will not help the drinking driver

Self-driving cars will not help the drinking driver

By Ian J. Faulks, Queensland University of Technology

There is an unexpected revolution underway in road safety. True, the highly visible community-wide programs continue, but behind the scenes there are major changes underway in how safety will be managed within road transport systems.

The self-driving car (or “autonomous vehicle”) has emerged with a practical suite of technologies for more efficient, safer, and eco-friendly road travel. This emergence has been rapid: for example, the Australian National Road Safety Strategy 2011-2020 did not canvas the possibility of such technologies.

The technology is already here

Self-driving cars are now approved for use on roads in several US states and may soon be on British roads. Self-driving cars are able to perform driving functions automatically. These vehicles use integrated systems of cameras, lidar, radar, and other sensors, as well as vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications and GPS navigation. These systems monitor the road environment and respond to changing traffic situations, roadway and weather conditions, and navigate to a destination without intervention from the vehicle occupant.

From what was once regarded as a futurist concept, autonomous vehicles are emerging as commercially viable. While fully self-driving cars may well be a decade or more away, the components that are necessary for the development of such vehicles are already in the marketplace. These include electronic stability control, advanced braking systems, active lane keeping, as well as a range of other in-vehicle safety technologies. Trials are underway to better understand the integration of crash avoidance technologies with “connected vehicles” utilising V2V and V2I technologies.

So what can the automated car do to address the “fatal five” causes of road trauma: speeding, alcohol-impaired and drug-impaired driving, failure to wear a seatbelt, driving while fatigued, and driving while distracted?

The autonomous vehicle revolution will likely have its major effects on controlling transitory behaviours such as speeding and unsafe manoeuvres associated with driver lapses and errors, rather than impacting on driver impairment or intentional risky behaviour. A seat belt interlock will prevent vehicle occupants from travelling unrestrained. As well as addressing safety issues, aspects such as route planning to reduce or avoid congestion and ecodriving are likely to be addressed through autonomous technologies.

Drink driving

We all know that drink driving is a crime: random breath testing and years of public education campaigns have taught us that. But still tens of thousands of people across Australia get in their cars and drive after drinking. That behaviour is the cause of significant injury and harm. The Australian National Road Safety Strategy 2011-2020 noted:

“… while drink driving behaviour has been contained to a small proportion of the driver (and rider) population, it continues to be a major cause of serious road trauma.”

Importantly, once intoxicated a person cannot decide to become un-drunk: the metabolism of alcohol takes time. Alcohol reduces inhibitory control, so even after one drink, decision-making as to the riskiness of driving after drinking may be altered in favour of driving. So decisions really need to be made whilst the blood alcohol level (BAC) is close to zero.

The current focus of drink driving countermeasures is to legislate for the use of alcohol ignition interlocks by convicted drink driver offenders. Additional measures include promotion of the use of personal breathalysers, education regarding standard drinks and the effects of alcohol, promotion of alternative transport options after drinking (e.g., designated drivers, or use of public transport), and requirements for drink drivers to attend traffic offender intervention programs.

Interlocks are a countermeasure typically used after a person has been convicted of drink driving. An interlock prevents subsequent re-offending, but doesn’t stop the first instance of drink driving (which has to be detected by police).

Can self- driving cars help the drink driver?

Will self-driving vehicles address drink driving, and in particular, the first offence problem? On the face of it, perhaps yes, but only if the fitment of an alcohol ignition interlock is mandatory for all vehicles.

However, there is a major legal hurdle. Even if it is an autonomous vehicle, the alcohol-impaired person is still the driver. After all, actions need to be taken to start the vehicle, enter instructions regarding destination and route, and engage the self-driving function. These actions constitute driving, and if you’re drunk, that’s drink driving.

Moreover, there are serious issues concerning the possible situations where a driver in an autonomous vehicle needs to intervene due to an emergency or system malfunction. Any such intervention constitutes driving, and again, if you’re drunk, that’s drink driving.

It comes back to the central safety questions regarding self-driving cars. First, what are the risks when automation takes a driver’s attention away from the continuous monitoring of what is happening on the road? And second, if there is a need to intervene, how do you get a driver’s attention so that a risky situation can be avoided?

If you’re alcohol-impaired and the controller of a self-driving car, these questions cannot be safely addressed.

Interlock devices are likely to stay

The best advice regarding alcohol use is simply “do not drive” whilst under the influence, and plan ahead to avoid doing so.

With new and integrated technologies such as self-driving cars, in future decades it may well be that car culture will fade away. A car will become a utilitarian device, simply necessary to support personal travel and the transport of goods, and no more than that.

But for drink driving, even in a world of autonomous cars, the solutions will remain with interlock devices to deter an alcohol-impaired person from driving, traffic enforcement to catch the drunken driver, and encouragement for the erstwhile drink driver to instead choose to become a passenger … in a cab, bus, or by travelling with a sober driver.

The Conversation

Ian J. Faulks MAP is a NRMA-ACT Road Safety Trust Research Scholar. He is affiliated with the Centre for Accident Research and Road Safety (CARRS-Q) at Queensland University of Technology and is an Honorary Associate with the Department of Psychology at Macquarie University. He is a member of the International Council on Alcohol, Drugs and Traffic Safety (ICADTS) and the Australasian College of Road Safety. He has previously received funding from the Transport Accident Commission in Victoria and the NSW Centre for Road Safety to investigate and review in-vehicle safety technologies.

The assistance of Professor Andry Rakotonirainy, CARRS-Q, and Nicholas Clarke, ANCAP Australasia Ltd in the preparation of this article is gratefully acknowledged.

This article was originally published on The Conversation.
Read the original article.