5,576 research outputs found
Automated Vehicles Have Arrived: What\u27s a Transit Agency to Do?
Ongoing innovations in automated and connected road vehicles create a path of radical transformation of personal mobility, the automotive industry, trucking, public transit, the taxi industry, urban planning, transportation infrastructure, jobs, vehicle ownership, and other physical and social aspects of our built world and daily lives.
In considering automated vehicle (AV) deployments and their cost, as well as the changes in traffic volume, congestion, rights of way, and the complexities of mixed fleets with both automated and non-automated vehicles, the time frame of impacts can only be surmised.
Still, it is worth considering a framework for understanding and managing the forthcoming process of change covered in this perspective
Full Potential of Future Robotaxis Achievable with Trip-Based Subsidies and Fees Applied to the For-Hire Vehicles of Today
As described by Grush and Niles in their textbook, The End of Driving: Transportation Systems and Public Policy Planning for Autonomous Vehicles, there are two distinct market states for the future of automobility as vehicles become increasingly automated. The first, Market-1, is comprised of all vehicles that are manufactured and sold to private owners and used as household vehicles. This private consumer fleet will—through automated driver assistance systems (ADAS)—be increasingly capable of hands-off operation, even self-driving in certain environments such as limited-access expressways. The second category, Market-2, represents all the vehicles made expressly for the service market, i.e., roboshuttles and robotaxis, meant to be eventually driverless in prepared, defined areas and streets. Ford, GM, Lyft, Uber, Waymo, and dozens of other companies assert that they are preparing vehicles for Market-2.
The main thesis in this perspective is that a productive, efficient system of on-demand Market-2 mobility can evolve from incentive-based governance—here termed “harmonization management.” This approach strikes a contrast with rigid regulation of a style seen with big city taxicabs and based on using constrained service classifications or per-vehicle medallion approaches. This essay recommends that transportation authorities set up systems of robust pricing signals—incentives and fees—delivered through a universal, mandatory system providing efficient, equitable distribution of these signals
The realism of William de Morgan.
Typewritten sheets in cover.
Thesis (M.A.)--Boston Universit
Assessing the Constitutionality of the Alien Terrorist Removal Court
In 1996, Congress created the Alien Terrorist Removal Court (ATRC). A court of deportation, the ATRC provides the U.S. attorney general a forum to remove expeditiously any resident alien who the attorney general has probable cause to believe is a terrorist. In theory, resident aliens receive different-and arguably far weaker-procedural protections before the ATRC than they would receive before an administrative immigration panel. In theory, the limited nature of the ATRC protections might implicate resident aliens\u27 Fifth Amendment rights. In practice, however, the ATRC has never been used. Perhaps to avoid an adverse constitutional ruling, the attorney general has never brought a deportation proceeding before the court. This Note examines the constitutionality of statutes underlying the ATRC that allow the government to rely on secret evidence. Although these provisions are constitutional on their face, they would be unconstitutional as applied in some circumstances. This Note concludes by suggesting how the ATRC\u27s secret-evidence provisions must be amended if the provisions are to become constitutional as applied in all circumstances
Measuring Impact: The Art, Science and Mystery of Nonprofit News
This report seeks to answer the two-pronged question, "What is 'impact,' and how can it be measured consistently across nonprofit newsrooms?" A review of recent, relevant literature and our informal conversations with experts in the field reveal growing ambitions toward the goal of developing a common framework for assessing journalism's impact, yet few definitive conclusions about how exactly to reach that framework. This is especially the case when journalism's "impact" is defined by its ultimate social outcomes -- not merely the familiar metrics of audience reach and website traffic. As with all journalism, the frame defines the story, and audience is all-important. Defining "impact" as a social outcome proves a complicated proposition that generally evolves according to the constituency attempting to define it. Because various stakeholders have their own reasons for wanting to measure the impact of news, understanding those interests is an essential step in crafting measurement tools and interpreting the metrics they produce. Limitations of impact assessment arise from several sources: the assumptions invariably made about the product and its outcome; the divergent and overlapping categories into which nonprofit journalism falls in the digital age; and the intractable problem of attempting to quantify "quality." These formidable challenges, though, don't seem to deter people from posing and attempting to find answers to the impact question. Various models for assessing impact are continually being tinkered with, and lessons from similar efforts in other fields offer useful insight for this journalistic endeavor. And past research has pointed to specific needs and suggestions for ways to advance the effort. From all of this collective wisdom, several principles emerge as the cornerstones upon which to build a common framework for impact assessment
Lifting homotopy T-algebra maps to strict maps
The settings for homotopical algebra---categories such as simplicial groups,
simplicial rings, spaces, ring spectra, etc.---are often
equivalent to categories of algebras over some monad or triple . In such
cases, is acting on a nice simplicial model category in such a way that
descends to a monad on the homotopy category and defines a category of homotopy
-algebras. In this setting there is a forgetful functor from the homotopy
category of -algebras to the category of homotopy -algebras.
Under suitable hypotheses we provide an obstruction theory, in the form of a
Bousfield-Kan spectral sequence, for lifting a homotopy -algebra map to a
strict map of -algebras. Once we have a map of -algebras to serve as a
basepoint, the spectral sequence computes the homotopy groups of the space of
-algebra maps and the edge homomorphism on is the aforementioned
forgetful functor. We discuss a variety of settings in which the required
hypotheses are satisfied, including monads arising from algebraic theories and
operads. We also give sufficient conditions for the -term to be calculable
in terms of Quillen cohomology groups.
We provide worked examples in -spaces, -spectra, rational
algebras, and algebras. Explicit calculations, connected to rational
unstable homotopy theory, show that the forgetful functor from the homotopy
category of ring spectra to the category of ring spectra
is generally neither full nor faithful. We also apply a result of the second
named author and Nick Kuhn to compute the homotopy type of the space
.Comment: 45 pages. Substantial revision. To appear in Advances in Mathematic
Protein Design is NP-hard
Biologists working in the area of computational protein design have never doubted the seriousness of the algorithmic challenges that face them in attempting in silico sequence selection. It turns out that in the language of the computer science community, this discrete optimization problem is NP-hard. The purpose of this paper is to explain the context of this observation, to provide a simple illustrative proof and to discuss the implications for future progress on algorithms for computational protein design
- …