1,659 research outputs found
Vacancy Reassessed
Since 1950, Philadelphia's population has been declining dramatically, by more than 30 percent. This rapid depopulation has led to the vacancy and abandonment of a large number of unmanaged residential lots and buildings. The future of Philadelphia rests on its ability to manage this decline, and in 1999, efforts were fragmented. This report highlights the barriers that many faced in trying to access vacant property and provides recommendations for a more strategic vision so that the city can create a significant and lasting impact
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Governance in niche development for a transition to a new mobility regime
Urban mobility is a difficult sustainability challenge; measures to reduce transport impacts produce only marginal reductions in overall energy use and CO2 emissions. Even fuel switch to electric vehicles and measures to manage traffic produce insufficient improvements. Seeking transport sustainability within the existing socio-technical regime involves policy approaches for dense cities to provide high-capacity, corridor-based public transport, expecting people to arrange their lives around such transport systems. Yet this socio-technical regime ill-fits modern mobility needs.
The reluctance to use public transport stems much from this 150 year old regime configuration. The social-technical landscape has shifted significantly: travel patterns are increasingly dispersed in space and time – not funnelled into traditional corridor peak-hour movements. The key is not getting people to return to travel patterns of 100 years ago, but in a transition to a socio-technical transport regime that delivers sustainability compatible with the 21st century social-technical landscape.
An opportunity may be emerging for socio-technical configurations in niche environments to effect transitions to alternate mobility futures. Autonomous vehicles are rapidly approaching market application. Since 2011, small autonomous pods have operated on segregated tracks at Heathrow Airport. In 2014 a similar system opened at the Suncheon Bay tourist area in South Korea.
Since 2011 there have been public street trials of autonomous vehicles in the USA and in 2015 they became street legal in the UK. The Milton Keynes (MK) ‘Pathfinder’ project focuses on two-seat pods which do not need segregated tracks, but will run on cycleways and footpaths, mixing with cyclists and pedestrians. Trials will start in 2015, on short distance links from the railway station to destinations in Central Milton Keynes. This project forms part of the wider Milton Keynes Future Cities Programme and Open University-led MK:Smart project.
This paper draws on these trials in MK to show through case study research how autonomous vehicles applications are moving beyond protected niches and, along with other developments, hold the potential to stimulate a major transition in public transport systems. The vehicles are small and each journey is individual to the passenger(s). Services do not run along corridor routes, like buses and trams, but are based on alternate rule-sets to the existing regime with individual journeys customised for each user. Such developments may therefore stimulate transition to totally different sorts of public transport systems and ultimately, socio-technical mobility regimes, by offering much more to users than any corridor system can provide. Rather than people adjusting their behaviour to bus routes, schedules and operating times, they travel directly, whenever they want, on services running 24/7. Thus these new regimes could be more compatible with lifestyle and economic trends that comprise 21st century socio-technical landscapes. As such, they provide credible alternatives to the private car, and so hold potential to deliver major sustainability gains.
But such transitions face major challenges from entrenched actors within the existing regime. Taxis, minicabs and bus operators would be threatened. If the Uber cab app is being blocked by incumbent actors, they look likely to be powerful opponents of autonomous vehicle based cab services. However, MK provides an interesting innovation context where there are several overlapping smart transport niches in different stages of development. As well as autonomous pods, demand responsive minibuses are planned and inductive changed electric buses are in service. If these projects build links to each other (niche accumulation), demonstrate economic value and reproduced beyond their original experimental spaces (niche proliferation), there is potential for them to overcome incumbent resistance. In Milton Keynes, these processes could be getting close to reaching critical mass, opening up the possibility of moving closer to radical regime transitions
Wear-Resistant Boride Nanocomposite coating Exhibits Low Friction
Many components experience sliding or rotating contact with other parts or with their environments. Their performance often degrades during service because their dimensions are altered by wear. Furthermore, the friction at the contact surface wastes energy. To mitigate these problems, hard coatings may be applied to contact surfaces to increase their wear resistance, and surfaces are often covered with a lubricant to reduce friction. At Ames National Laboratory, a nanocomposite boron-aluminum-magnesium ceramic alloy coating (AlMgB14 + TiB2) has been developed that provides a superhard, wear-resistant surface that also has an exceptionally low coefficient of friction. Tests show that these boride coatings offer a combination of wear resistance and low friction unmatched by other hard mate - rials (e.g., tungsten carbide, cubic boron nitride, or diamondlike carbon)
Cook\u27s Field Guide to Prosecution in Georgia
In this practical guidebook former district attorney and director of the University of Georgia\u27s School of Law Prosecutorial Justice Program Alan Cook shares his personal wisdom and advice gathered from his decades of experience into a single volume. The handbook includes introductions to each chapter topic, plus both quick and detailed reference sections on all aspects of criminal law and procedure. It also includes useful appendices with step-by-step practice guides for how to perform specific prosecutorial tasks (such as how to take a guilty plea). Law student testimonies from now seasoned attorneys at the start of the book indicate the potential for this set of resources to students interested in becoming prosecutors as well as those already practicing.https://digitalcommons.law.uga.edu/books/1159/thumbnail.jp
Consuming the million-mile electric car
Unlike for many consumer products, there has been no strong environmental case for extending the life of internal combustion engine cars as the majority of their environmental impact is fuel consumed in use and not the energy and materials involved in manufacturing. Indeed, with improving fuel efficiency, product life extension is environmentally undesirable; older, less fuel-efficient cars need to be replaced by newer more fuel-efficient models. Electric vehicles (EVs) are predominantly considered environmentally beneficial by using an increasingly decarbonised fuel – electricity. However, LCA analyses show that EVs have substantial environmental impacts in their materials, manufacturing and disposal. The high ‘embedded’ environmental impacts of EVs fundamentally change the case for product life extension. Thus, product life extension is desirable for EVs and they are suited to it. While petrol and diesel cars have an average lifetime mileage of 124,000 miles (200,000 Kilometres), the case for the million-mile (1.6 million Kilometre) electric car appears strong. Although it may be technically possible to produce a million-mile EV, how will such vehicles be consumed given that the car consumption is complex, involving, for example, extracting use and symbolic value? In this contribution we explore the nature of the relationship between cars and the consumer that moves beyond technical and functional value to understand what form of access consumers require to an EV across its entire 50-year life. If such consumption aspects are overlooked then, even if the million-mile car is technically viable, it is unlikely to be adopted and the environmental benefits they may yield will be lost.Peer reviewedFinal Accepted Versio
A Study of Heat Transfer in Rotary Desorbers Used to Remediate Contaminated Soils.
A comprehensive heat transfer model is developed which describes heat transfer phenomena in rotary desorbers. This model predicts the temperatures of the solids bed and gases in the desorber and the rate of water evaporation from the solids. Emphasis is placed on describing the heat transfer process between the rotating wall of a desorber and the adjacent bed of solids. A heat-balance integral method is used to model heat conduction from the wall to adjacent wet bed particles. This solution includes the effects of water evaporation near the wall and a thermal contact resistance between the wall and the first layer of particles. The model allows for water evaporation before the bulk bed temperature reaches the saturation temperature of the water. Radiative and convective heat transfer to the solids are coupled with the wall-to-bed heat transfer rate to find the total heat transfer rate to the solids. Energy balances are performed on an axial zone of the desorber and are used to find the resulting change in solids and gas temperatures across the zone, thereby predicting axial temperature profiles. Experiments are performed on a batch-type, pilot-scale desorber. A bed temperature probe is used to determine the transient temperature of the bed at several radial and axial locations. In these experiments, the particle size, the rotation rate, and the initial moisture content of the solids are varied. It is found that particles heated by the rotating wall are not completely mixed with the remainder of the bed, reducing wall-to-bed heat transfer. Evaporation rates are inferred from measured velocities at the exit of the desorber. Mass balances are performed on the water, with good results. A significant amount of water is found to evaporate before the bulk bed temperature reaches the water saturation temperature. The measured bed temperatures and evaporation rates compare favorably to predictions of the model. The important features of the experimental data, including the bulk bed temperature profiles and water evaporation before the bed temperature reaches the water saturation temperature, are predicted
The Willingness to Pay for Mortality Risk Reductions: A Comparison of the United States and Canada
We present results for two contingent valuation surveys conducted in Hamilton, Canada and the US to elicit WTP for mortality risk reductions. We find similar Value of Statistical Life estimates across the two studies, ranging from USD 930,000 to USD 4.8 million (2000 US dollars). WTP increases with risk reduction size, but varies little with respondent age: individuals aged over 70 years hold WTP values approximately one-third lower than other respondents. Respondent health status has limited effect on WTP. These results provide little or no evidence for adjusting VSL estimates used in policy analyses for the affected population’s age or health status.value of a statistical life, mortality risks, benefit-cost analysis
Superabrasive boride and a method of preparing the same by mechanical alloying and hot pressing
A ceramic material which is an orthorhombic boride of the general formula: AlMgB14:X, with X being a doping agent. The ceramic is a superabrasive, and in most instances provides a hardness of 40 GPa or greater
Ceramic comprising an orthorhombic aluminum magnesium boride of formula: almgb14:x, wherein x is a doping agent present in from 5 to 30 weight % selected from group iii, iv, and v elements; extreme hardness; wear resistant coatings
A ceramic material which is an orthorhombic boride of the general formula: AlMgB14 :X, with X being a doping agent. The ceramic is a superabrasive, and in most instances provides a hardness of 40 GPa or greater
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