Calero-Valenzuela, Carlos A.

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    Factores de calidad de servicio para el sistema de carros públicos
    (2010-12) Calero-Valenzuela, Carlos A.; Figueroa-Medina, Alberto M.; College of Engineering; Valdés Díaz, Didier; Ortiz García, Cecilio; Department of Civil Engineering; Resto, Pedro
    The “Carros Públicos” is a special demand response transit service operating in Puerto Rico. The sustained reduction in the system ridership could be related to its poor quality of service, as perceived by the population, and the high motorization rate on the Island, among other factors. A survey of 368 people identified the vehicle’s cleanliness, comfort, and amenities, the operator’s kindness, the service reliability, the passenger load, and the security in the vehicles and stops as the preferred quality of service measures. A logistic regression identified the waiting time, the disposition to walk, motor vehicle ownership, and the person’s age and occupation as the main factors that influence the decision to use the “Carros Públicos”. In order to increase its quality of service and ridership, the “Carros Públicos” need to establish incentives to increase the hours of operation, improve the accessibility and security of the transit stops, develop a marketing campaign, and use vehicles with more amenities and comfort.
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    Metodología para la evaluación de la consistencia de diseño de carreteras rurales de dos carriles
    (2015) Calero-Valenzuela, Carlos A.; Cruzado-Vélez, Ivette; College of Engineering; Valdés Díaz, Didier; Vega, Fernando; Figueroa Medina, Alberto M.; Department of Civil Engineering; Rodríguez Álamo, Betzabé
    The road geometric design consistency is correlated with its level of safety. This evaluation is performed in three stages: measure or estimation of the operational speed, calculation of the dependent variable in the geometric design consistency scale, and its classification through the scales. To include vertical alignment elements in the speed estimation and geometric design, consistency evaluation may consider as many effects which might vary the operating speed in horizontal curves. The main objective of this dissertation was to develop a methodology that estimate the 85th percentile of the speed differences between consecutive points in a horizontal curve (Δ85VBP), and scales to assess the geometric design consistency using this variable. Geometric data of 38 horizontal curves in two lane rural roads in the West area of Puerto Rico were collected. Free flow speeds of 22,020 users in five points of these horizontal curves were gathered. Sight distance, length between points, degree of curvature, horizontal alignment element, and functional classification were identified as the significant variables to the estimation of Δ85VBP. These were implemented to feed an Artificial Neural Network (ANN) for the estimation of Δ85VBP. An optimal architecture LMBP[48:3:4] was with an average coefficient of determination (R2) of 0.5. Scales for the evaluation of geometric design consistency in tangents and horizontal curves through Receiver Operating Curves (ROC) were developed. Three levels of geometric design consistency for horizontal curves were developed: GOOD if Δ85VBP < 3 MPH, FAIR if 3 MPH ≤ Δ85VBP < 4 MPH, and POOR if Δ85VBP ≥ 4 MPH. In tangents the results were: GOOD if Δ85VBP < 4 MPH, FAIR if 4 MPH ≤ Δ85VBP < 5 MPH, and POOR if Δ85VBP ≥ 5 MPH.