Parametric analysis of nightside conductance effects on inner magnetospheric dynamics for the 17 April 2002 storm

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95027/1/jgra17945.pd

Understanding storm‐time ring current development through data‐model comparisons of a moderate storm

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94635/1/jgra18489.pd

Customer satisfaction with bus rapid transit: a study of New York City select bus service applying structural equation modeling

Like any other transit mode, bus rapid transit (BRT) has a number of service quality and performance attributes that can affect rider satisfaction. However, there is little understanding about BRT rider satisfaction. This study investigates the relationship between riders’ overall satisfaction and underlying driving factors of the BRT service in New York City (NYC), known as select bus service (SBS). Two conceptual structures are developed for three groups of SBS riders based on theoretical review and pilot survey. Hypotheses about relationships between latent variables and observed variables are developed. Survey data obtained from interviewing riders on buses and at bus stops are used to test the hypotheses by applying structural equation modeling (SEM). For each group of riders, one model was built. Acceptable fits were obtained for all three models. In addition, some of the proposed causal relationships were supported in these models. Accepted hypotheses suggest that service quality was the most important factor influencing overall satisfaction for all three kinds of riders, namely, frequency, on-time performance, and speed. The other significant attributes are bus-only lanes, buses with three doors, bus comfort and cleanliness, proximity of bus stops, real-time information, limited stops, and ticket system attributes. Their effects vary among riders on routes with different locations and between rider groups with and without awareness of travel information. The implications of the findings for future planning and system improvement are discussed. In this study, SEM is found to be an appropriate methodology for measuring rider satisfaction levels. The findings are useful for the agencies in NYC and other cities in a similar situation to justify and plan transit service with limited resources

Rider perception of a “light” Bus Rapid Transit system - The New York City Select Bus Service

The Bus Rapid Transit (BRT) system in New York City (NYC), called Select Bus Service (SBS), is a “light” BRT system with some but not all BRT features. Focusing on it, this study aims to contribute to a better understanding of riders\u27 perceptions of BRT service implemented with limited space and capital funding. A total of 1700 SBS riders on four routes were interviewed using the survey methodology developed in this study. Statistical analysis and regression modeling were used to analyze rider socio-demographics, investigate the relationship between rider satisfaction levels, and the key factors driving them. The results show that, while most of them are transit dependent, new SBS riders are mainly attracted by better service and accessibility. Riders on different routes were found to have different socio-demographics. The statistical tests of satisfaction means provide further insight into the disparity in service evaluation between/among groups of riders (e.g. gender, experience, weather, route, trip purpose). Service frequency, speed, and on-time performance were found to have a positive influence on rider satisfaction across all routes. Variables related to off-board ticket machines and travel information are more valued than others. The effects of external factors vary according to characteristics of the routes and rider groups. This study suggests potential applications of the results for future planning and improvement to increase rider satisfaction and thereby retain and increase ridership

Select Bus Service on M15 in New York City Bus Rapid Transit Partnership

Constrained and congested streets hinder accelerated transit service and the provision of protected space for cycling. Although bus rapid transit has proved effective at improving transit service in cities, the addition of a physical priority for transit must be balanced against competing needs for traffic flow and parking, particularly in areas with high levels of activity. On October 10, 2010, the New York City Transit Authority of the Metropolitan Transportation Authority—now known as MTA New York City Transit—and the New York City Department of Transportation implemented the M15 select bus service on First and Second Avenues. This bus rapid transit service generated a significant improvement to transit service in a constrained corridor and created space for safe bicycling facilities and pedestrian safety improvements, and all general traffic flow along the corridor was maintained. The M15 select bus service improved bus speed and reliability with proof-of-payment fare collection, new bus lanes, and improved bus lane treatments, including offset bus lanes (next to the parking lane). Passenger comfort and reliability were also enhanced through route simplification, improved scheduling, enhanced stations, and better customer information. The results have been noteworthy, with a 15% to 18% improvement in travel time and a 10% increase in corridor ridership. Cycling has also increased substantially along the corridor, on which new parking-protected bike lanes were installed as part of the project. These gains were achieved through close coordination with all corridor stakeholders, careful use of priority treatments on parts of the corridor, and the close working partnership between the New York City Department of Transportation and MTA New York City Transit

Highly Active Protein Surfaces Enabled by Plant-Based Polyphenol Coatings

Proteins represent complex biomolecules capable of wide-ranging but also highly specific functionalities. Their immobilization on material supports can enable broad applications from sensing and industrial biocatalysis to biomedical interfaces and materials. We demonstrate the advantages of using aqueous-processed cross-linked polyphenol coatings for immobilizing proteins, including IgG, avidin, and various single and multidomain enzymes on diverse materials, to enable active biofunctional structures (e.g., ca. 2.2, 1.7, 1.1, and 4.8 mg·m-2 active phosphatase on nanoporous cellulose and alumina, steel mesh, and polyester fabric, respectively). Enzyme assays, X-ray photoelectron spectroscopy, silver staining, supplemented with contact angle, solid-state 13C NMR, HPLC, and ESI-MS measurements were used to characterize the polyphenols, coatings, and protein layers. We show that the functionalization process may be advantageously optimized directly for protein activity rather than the traditional focus on the thickness of the coating layer. Higher activities (by more than an order of magnitude in some cases) and wider process pH and material compatibility are demonstrated with polyphenol coatings than other approaches such as polydopamine. Coatings formed from different plant polyphenol extracts, even at lowered purity (and cost), were also found to be highly functional. Chemically, our results indicate that polyphenol coatings differ from polydopamine mainly because of the elimination of amine groups, and that polyphenol layers with intermediate levels of reactivity may better lead to high immobilized protein activity. Overall, an improved understanding of simple-to-use polyphenol coatings has been obtained, which enabled a significant development in active protein surfaces that may be applied across diverse materials and nanostructured supports. © 2018 American Chemical Society