54 research outputs found
Bus Transit Operational Efficiency Resulting from Passenger Boardings at Park-and-Ride Facilities
In order to save time and money by not driving to an ultimate destination, some urban commuters drive themselves a few miles to specially designated parking lots built for transit customers and located where trains or buses stop. The focus of this paper is the effect Park-and-Ride (P&R) lots have on the efficiency of bus transit as measured in five bus transit systems in the western U.S. This study describes a series of probes with models and data to find objective P&R influence measures that, when combined with other readily-available data, permit a quantitative assessment of the significance of P&R on transit efficiency. The authors developed and describe techniques that examine P&R as an influence on transit boardings at bus stops and on bus boardings along an entire route. The regression results reported are based on the two in-depth case studies for which sufficient data were obtained to examine (using econometric techniques) the effects of park-and-ride availability on bus transit productivity. Both Ordinary Least Square (OLS) regression and Poisson regression are employed. The results from the case studies suggest that availability of parking near bus stops is a stronger influence on transit ridership than residential housing near bus stops. Results also suggest that expanding parking facilities near suburban park-and-ride lots increases the productivity of bus operations as measured by ridership per service hour. The authors also illustrate that reasonable daily parking charges (compared to the cost of driving to much more expensive parking downtown) would provide sufficient capital to build and operate new P&R capacity without subsidy from other revenue sources
Measuring the Economic Impact of High Speed Rail Construction for California and the Central Valley Region
The nation’s first high-speed rail project is under construction in California’s Central Valley as of the date of this report. This research analyzes the immediate economic impacts, focused on employment and spending generated by California High-Speed Rail (HSR) Construction Package 1 (CP1) in the Central Valley and the rest of California. The authors use a two-pronged approach that combines original economic analysis and modeling with case study vignettes that explore the economic impacts through the lens of a sample of businesses and individuals directly impacted by this phase of HSR development. Overall, the economic analysis suggests that CP1-related spending (forecasted through to 2019) will lead to more than 31,500 additional jobs (both part-time and full-time) by the year 2029. Growth is concentrated in Fresno County, with the number of additional jobs estimated at more than 15,500. The analysis considers job growth across a number of alternative scenarios, converting the raw jobs estimates to full-time equivalent job-years. Under the most conservative HSR spending scenario considered, over the 15-year period evaluated, more than 25,000 full-time equivalent job-years are created. This amount to 14,900 jobs per billion (real) dollars of spending, or a cost of approximately $67,200 per job-year
Steps to Supplement Park-and-Ride Public Transit Access with Ride-and-Ride Shuttles
Public transit ridership in California declined in the five years before the pandemic of 2020–21 and dropped significantly further after the pandemic began. A sharp downward step in the level of transit boarding occurred after February 2020, and continues to the date of this report as a result of the public-health guidance on social distancing, expanded work-at-home, and a travel mode shift from public transit to private cars. A critical issue has come to the foreground of public transportation policy, namely, how to increase the quality and geographic reach of transit service to better serve the essential trips of mobility disadvantaged citizens who do not have access to private vehicle travel. The research focus of this report is an examination of the circumstances where fixed route bus route service could cost-effectively be replaced by on-demand microtransit, with equivalent overall zone-level efficiency and a higher quality of complete trip service. Research methods were reviews of documented agency experience, execution of simple simulations, and sketch-level analysis of 2019 performance reported in the National Transit Database. Available evidence is encouraging and suggestive, but not conclusive. The research found that substitutions of flexible microtransit for fixed route buses are already being piloted across the U.S., with promising performance results. The findings imply that action steps could be taken in California to expand and refine an emphasis on general purpose microtransit in corridors and zones with a relatively high fraction of potential travelers who are mobility disadvantaged, and where traditional bus routes are capturing fewer than 15 boardings per vehicle hour. To be sufficiently productive as fixed route replacements, microtransit service technologies in the same or larger zones need to be capable of achieving vehicle boardings of five per hour, a challenge worth addressing with technology applications. Delivery of microtransit service can be undertaken through contracts with a growing set of private sector firms, which are developing processes to merge general purpose customers with those now assigned to ADA-required paratransit and Medi-Cal-supported non-emergency medical transport
Does reducing spatial differentiation increase product differentiation? Effects of zoning on retail entry and format variety
Polymorphous adenocarcinoma of the salivary glands : reappraisal and update
Although relatively rare, polymorphous adenocarcinoma (PAC) is likely the second most common malignancy of the minor salivary glands (MiSG). The diagnosis is mainly based on an incisional biopsy. The optimal treatment comprises wide surgical excision, often with adjuvant radiotherapy. In general, PAC has a good prognosis. Previously, PAC was referred to as polymorphous low-grade adenocarcinoma (PLGA), but the new WHO classification of salivary gland tumours has also included under the PAC subheading, the so-called cribriform adenocarcinoma of minor salivary glands (CAMSG). This approach raised controversy, predominantly because of possible differences in clinical behaviour. For example, PLGA (PAC, classical variant) only rarely metastasizes, whereas CAMSG often shows metastases to the neck lymph nodes. Given the controversy, this review reappraises the definition, epidemiology, clinical presentation, diagnostic work-up, genetics, treatment modalities, and prognosis of PAC of the salivary glands with a particular focus on contrasting differences with CAMSG.Peer reviewe
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