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Minimum parking requirements (MPRs) have been criticized for creating excess parking, degrading urban form, reducing housing affordability, and encouraging automobile dependency. As a result, many American cities have begun to reduce or remove parking minimums in some or all areas. However, existing research on the effects of these policy changes has focused only on the analysis of parking supply. We investigated the broader results of parking reform at a small university city in the Midwest that removed MPRs for downtown and university districts. Our quasi-experimental research found that onsite parking construction in the deregulated zones decreased dramatically, from 108% of the earlier requirement to only 46%, clearly indicating that MPRs had enforced oversupply of parking. Of the 43 new major developments built in the 7 years following the parking reform, 84% provided less parking than previous requirements, including eight developments with zero parking. The reduction in onsite parking led to more efficient use of existing parking stock, both public and private. Furthermore, the removal of MPRs, combined with other policies, helped improve urban form by increasing housing density, promoting active building frontages, and guiding a growing share of new developments to transit-rich and walkable districts. American cities stand to benefit greatly by relaxing or repealing parking requirements. Cities that expect resistance to parking reforms can take a targeted and incremental approach, first removing MPRs in denser areas such as downtowns, transit corridors, and other prime districts where an oversupply of parking is typically being reinforced by uniform MPRs. The case of Champaign (IL) demonstrates that a targeted district-scale reform is likely to encounter minimal opposition. [ABSTRACT FROM AUTHOR]

Despite ever-increasing public and financial support for public transportation in recent decades, transit ridership has dropped substantially in the 2010s across the United States. While many theories that explain the reasons behind the decline in ridership have been proposed, no consensus on the primary causes has been reached. By employing gradient boosting decision tree and counterfactual simulations, we examine the complex relationships between transit ridership and key internal and external factors from 2002 to 2017 in 85 of the largest urbanized areas in the US. Among several contributing factors, the declining cost of driving, measured by the decreasing share of carless households combined with lower gasoline prices, was the salient, most influential factor behind the recent decline. Neighborhood change in high-density neighborhoods also led to a moderate net loss in ridership. The only factor that has been mitigating further decline was an increase in transit services. Had this increase not occurred, loss of ridership would have been more than double the actual loss during the study period. [ABSTRACT FROM AUTHOR]

This research aims to augment human cognition through the advancement and automation of mindmapping technologies, which could later support human creativity and virtual collaboration. Mindmapping is a visual brainstorming technique that allows problem solvers to utilize the human brain's ability to retrieve knowledge through similarity and association. While it is a powerful tool to generate concepts in any phase of s or design, the content of mindmaps is usually manually generated while listening or conversing and generating ideas, requiring a high cognitive load. This work introduces the development of a speech-driven automated mindmapping technology, called Speech2Mindmap. The specifics of the Speech2Mindmap algorithm are detailed, along with two case studies that serve to test its accuracy in comparison to human-generated mindmaps, using audio recorded speech data as input. In the first case study, the Speech2Mindmap algorithm was evaluated on how well it represents manually generated human mindmapping output. The second case study evaluated the reliability of the Speech2Mindmap algorithm and examined the best performing methods and conditions to achieve the greatest similarity to human-generated mindmaps. This research demonstrates that the Speech2Mindmap algorithm is capable of representing manually generated human mindmapping output and found the best performing methods and conditions to generate a mindmap that is 80% similar, on average, to human-generated mindmaps. [ABSTRACT FROM AUTHOR]

Various qualities of transit services, including travel time, frequency, and the presence of alternative paths, affect accessibility—how easily passengers can reach their destinations by transit. Traditional accessibility metrics, such as gravity-type and cumulative-opportunity indices, rely exclusively on travel time as a proxy for travel impedance, failing to consider other qualities of transit services. This study develops a comprehensive transit-based job accessibility index that accounts for the number of feasible alternative routes and their frequency in addition to in-vehicle and out-of-vehicle travel times. It uses the General Transit Feed Specification (GTFS) data and Dijkstra's shortest path algorithm to compute these components of tract-to-tract transit trips in the Chicago Metropolitan Statistical Area (MSA). We demonstrate that conventional accessibility indices considering only gross travel time overestimate job accessibility in the job rich downtown area and suburban train hubs, while they tend to underestimate job accessibility in places mainly served by a suburban bus system. Logistic regression analysis shows that our refined job accessibility measure explains the likelihood of transit commute considerably better than conventional measures. [ABSTRACT FROM AUTHOR]

This study investigates neighborhood scale net migration of young adults in the top 20 urbanized areas (UAs) in the United States between 1980 and 2010. Both descriptive and regression analyses show that Generation Xers and Millennials were more likely to net migrate into central locations and less aversive to high density at their young ages than late boomers were in the 1980s. Consumption amenities are a critical factor that distinguishes the net migration patterns between young and old adult groups and became a more important location factor for young adults in the 2000s (late Gen Xers and older Millennials) than in the 1990s (early Gen Xers). There exists a considerable degree of heterogeneity across UAs and neighborhoods even within the same UAs. [ABSTRACT FROM AUTHOR]

Problem, research strategy, and findings: A shift toward more sustainable transportation requires both adequate pricing of externalities from driving and supportive land use policies. However, proponents of each approach often under-estimate the complementarity and potential synergy between them. This study investigates the interaction effects between gasoline prices and land use (policy) variables using a panel dataset of transit ridership in 67 urbanized areas between 2002 and 2010. We found that while doubling the average gasoline price would increase transit ridership by 8.4% in an urbanized area with mean density and no regional containment policy, in areas with slightly higher density and a regional containment policy, the impact of higher gasoline prices would rise to 21%. In communities that had adopted a package of smart growth land use options, the impact of higher gasoline prices on transit use is even greater. Takeaway for practice: Pricing schemes will be more effective where alternatives to automobility and supportive land use policies exist. The impacts of urban form on travel behavior are also strengthened when driving externalities are correctly priced. Planners and policymakers should take advantage of the complementarity between pricing and land use planning approaches by implementing policies in combined and well-coordinated ways. [ABSTRACT FROM AUTHOR]

The agricultural sector is highly vulnerable to bioterrorism attacks with the potential for severe economic consequences. This article presents estimates of state-by-state total economic impacts of a hypothetical agroterrorism attack that uses foot-and-mouth disease (FMD) pathogens, which is one of the most contagious animal diseases and can be easily weaponized. The authors estimate the economic impacts across the U.S. states by applying the National Interstate Economic Model (NIEMO), a multiregional input output (MRIO) model. Total economic impacts range from $23 billion to $34 billion. The overwhelming sources of the losses are due to domestic and international demand cuts. The results of this research highlight the point that the economic impacts are nationwide, regardless of the location of the attack because of large-scale export losses. [ABSTRACT FROM PUBLISHER]

The purpose of this paper is two-fold. First, we suggest an analytical framework to study the full economic impacts of hypothetical bio-terrorist attacks on various targets. We particularly emphasize the importance of estimating economic impacts that occur through systems and behavior linkages beyond direct losses. Second, we provide a case study that analyzes the economic impacts of an attack on a major league sports stadium. The estimated loss from the stadium attack ranges from $62 billion to $73 billion. The largest loss comes from the loss of lives, followed by the reduced demand for sports stadium visits. We demonstrate that available off-the-shelf impact models (in this case IMPLAN) can be utilized, via the development of detailed but plausible scenarios grounded in available data and literature. [ABSTRACT FROM AUTHOR]

To highlight the role of sustainable urban spatial structure in reducing household vehicle miles traveled (VMT) and CO 2 emissions, this empirical study of the 121 largest urban areas (UAs) in the U.S. compares the effects of local land use and UA scale spatial structure in a multilevel analysis framework. The results show that centralized population and mezzo scale jobs-housing balance as well as higher UA population density can significantly reduce VMT and CO 2 emissions. The combined effects of all UA level variables, including population-weighted density (PWD), are found to be on par with the elasticity of VMT with regard to a census tract level compactness index. Further, we find that urban spatial structure moderates local urban form effects on travel behavior. For example, while 10% more compact census tracts are associated with 5% fewer VMT in UAs with the sample average PWD, such as St. Louis and Pittsburgh, this estimated local effect increases to 7.5% and 10% in UAs where PWD is as high as in Chicago and New York, respectively. The findings of this study strongly support policy programs that aim to boost "articulated densities" in the urban region and call for stronger institutional frameworks for regional planning. • Urban area density, centrality and jobs-housing mix affect VMT and CO 2 emissions • Urban structure affects VMT and CO 2 emissions as much as local land use • Urban structure moderates local urban form effects on travel behavior • Elasticity of VMT w.r.t. local compactness increases with urban area density [ABSTRACT FROM AUTHOR]

This paper presents an analysis of magnetic resonance coupling effects that can be considered for realizing a wireless power transfer (WPT) system. In this study, numerical analysis is applied to investigate the power transfer characteristics affected by coil inductance and placement. The simulations and experiments, using various coils and positions, are conducted to find the optimum power transfer condition. The experiment shows that the frequency bandwidth of the wireless power transfer at the optimum coupling condition is enlarged to 0.73 MHz and the transfer efficiency is maintained at over 80%. [ABSTRACT FROM PUBLISHER]

Few studies empirically estimate the effects of metropolitan growth on nonmetropolitan communities at a national scale. This paper estimates the growth effects of 276 MSAs on population in 1,988 nonmetropolitan communities in the United States from 2000 to 2007. We estimate the distance for growth spillovers from MSAs to nonmetropolitan communities and test the assumption that a single MSA influences growth. We compare three methods of weighting cities' influence: nearest city only, inverse-distance, and relative commuting flow to multiple cities. We find the inverse-distance approach provides slightly more reliable and theoretically supportable results than the traditional nearest city approach. [ABSTRACT FROM AUTHOR]