Luca Quadrifoglio

Texas A&M University | TAMU · Department of Civil Engineering

We consider a ridesharing service in which no driver and rider’s roles are pre-determined, but left to decide by the system to further reduce costs compared to the typical version with preassigned roles. Travelers are motivated to participate in the service by saving individual transportation costs and accept its rules. We first formally define it...

This paper addresses one of the most challenging issues in designing an efficient and sustainable ridesharing service: ridesharing market design. We formulate it as a fair cost allocation problem through the lens of the cooperative game theory. A special property of the cooperative ridesharing game is that its characteristic function values are cal...

This paper proposes a novel heuristic to solve the network design problem for public transport in small-medium size cities. Such cities can be defined as those with a diameter of a few kilometers with up to a few hundred thousand residents. These urban centers present a specific spatial configuration affecting the land use and mobility system. Tran...

This paper studies a problem in which a distribution center of a chain store packages a small subset of a large number of available products (e.g. DVDs) to distribute to its local stores. Only a limited number of different packages are allowed. We determine what products are in each package and what package to distribute to each store for revenue m...

ADA paratransit services are a very large and ever-growing industry providing door-to-door transportation services for people with disability and elderly customers. Paratransit system, however, just like all other public transportation systems, suffers from travel time variability due to various factors and as a result gives its customers unreliabl...

Congestion toll pricing is an inexpensive management way to mitigate the traffic congestion and reduce the delay in the network. One of the models that were proposed for toll pricing is the minimum toll revenue (MinRev) problem. The objective of this model is to find link-tolls that simultaneously cause users to efficiently use the network and to m...

To maximize private vehicle usage efficiency and alleviate urban congestion, many studies and actual field operations on vehicle sharing have been done since the mid ‘90s. The classic carsharing system, which is known as a round-trip, is operated out of fixed stations so that customers can pick up and drop off the vehicle at the same station. Altho...

The goal for transit signal priority (TSP) strategies is to improve the efficiency of urban transportation systems by promoting fast passage of system users. However, because conventional vehicle detection technologies require TSP strategies to be vehicle based, TSP may not lead to optimal results for person delay. This paper proposes a signal cont...

Paratransit services constitute a large industry that provides transportation services to disabled and elderly customers across the country. Demand for these services has been growing since the Americans with Disabilities Act (ADA) was signed into law in 1990 and will continue to grow in the foreseeable future. Rather than adopt a centralized opera...

A reliable method for predicting paratransit ridership is important, especially for the efficiency of the services offered. The commonly used aggregate regression model is most accurate for forecasting the total demand for regional areas such as whole counties or cities; however, it is likely to be geographically inaccurate. This paper proposes a g...

a b s t r a c t This paper defines a novel street Connectivity Indicator (C.I.) to predict transit performance by identifying the role that street network connectivity plays in influencing the service quality of demand responsive feeder transit services. This new C.I. definition is dependent upon the expected shortest path between any two nodes in...

a b s t r a c t The general lack of first/last mile connectivity is one of the main challenges faced by today's public transit. One of the possible actions towards a solution to this problem is the planning, design and implementation of efficient feeder transit services. This paper develops an analytical model which allows for an easy computation o...

Americans with Disabilities Act (ADA) paratransit systems are dial-a-ride services that provide public transportation to disabled customers. In large metropolitan areas, these services might use zoning strategies to simplify their management. The objective of this paper is to provide a more in-depth evaluation and comparison between centralized and...

This paper presents a methodology to identify and locate critical links in a grid street network system for feeder transit services. A ‘critical’ link can be defined as a link that—when eliminated from or appended to an existing network—would cause the largest change in the network connectivity and consequently in the transit performance. The most...

This paper presents a simulation study to evaluate the capacity and the optimum service cycle time of a demand responsive transit “feeder” service within the colonia of El Cenizo, TX. Demand data are taken from a survey questionnaire conducted to evaluate the existing travel patterns and the potential demand for a feeder service. Results showed tha...

Serving one of the largest metropolitan areas in the United States, the George Bush Intercontinental Airport (IAH) in Houston, Texas, is one of the 10 airports with the longest average taxi-out and taxi-in times. This paper assesses the congestion at IAH by analyzing taxi times and flight data during different hours of the day. The capacity of IAH...

This paper evaluates the effects of including transfers between service zones on overall service performance in a paratransit system. Transfers were included to improve the operational efficiency of a system when maintenance of a desirable zoning structure was obligatory. This proposed innovative service design was compared with more traditional ca...

New quay cranes (QCs) have been designed to increase terminal productivity by lifting more containers simultaneously. But QC productivity relies on efficient cooperation with the vehicles carrying the containers. This paper investigates the synchronization scheduling problem between the automated guided vehicles and these new QCs. The problem is fo...

The recent US Commodity Flow Survey data suggest that transporting hazardous materials (HAZMAT) often involves multiple modes, especially for long-distance transportation. However, not much research has been conducted on HAZMAT location and routing on a multimodal transportation network. Most existing HAZMAT location and routing studies focus exclu...

This article proposes to solve the oversaturated network traffic signal coordination problem using the Ant Colony Optimization (ACO) algorithm. The traffic networks used are discrete time models which use green times at all the intersections throughout the considered period of oversaturation as the decision variables. The ACO algorithm finds intell...

The mobility allowance shuttle transit (MAST) system is an innovative hybrid transit system in which vehicles are allowed to deviate from a fixed route to serve flexible demand. In this paper, we develop an insertion heuristic that economically inserts the deviation requests into the schedule for multiple-vehicle MAST system, which has never been a...

The mobility allowance shuttle transit (MAST) system is a hybrid transit system in which vehicles are allowed to deviate from a fixed route to serve flexible demand. A mixed integer programming (MIP) formulation for the static scheduling problem of multi-vehicle MAST (m-MAST) system is proposed in this paper. Based on the MIP formulation, we analyz...

This paper presents a simulation study to evaluate the capacity and the optimum service cycle time of a demand responsive transit “feeder†service within the colonia of El Cenizo, TX. Demand data are taken from a survey questionnaire conducted to evaluate the existing travel patterns and the potential demand for a feeder service. Results showed...

The objective of this research was to develop a multiobjective optimization model to deploy emissions reduction technologies for nonroad construction equipment to reduce emissions in a cost-effective and optimal manner. Given a fleet of construction equipment emitting different pollutants in the nonattainment (NA) and near -nonattainment (NNA) coun...

Feeder transit services perform the crucial first/last mile access to transit by connecting people within a residential area to a major transit network. In this paper, we address the optimal zone design problem faced by planners for feeder transit services with high demands and long length of service area, where a two-vehicle operation is assumed t...

The goal of this paper was to develop a performance measurement–based approach for transportation agencies, such as state departments of transportation, to evaluate and enhance sustainability. This research proposes a performance measurement–based framework and evaluation methodology for sustainable transportation, linked to agency strategic planni...

This paper presents a methodology to identify and locate critical links in a grid street network system for feeder transit services. A 'critical' link can be defined as that link which when eliminated from or appended to an existing network would cause the largest change in the network connectivity and consequently transit performance. The most sig...

We assess the impact of accounting for nonlinearity of selected value functions to improve the multiattribute utility theory approach for transportation planning applications. Research findings were obtained by conducting a case study for investigating and improving the project evaluation and selection with the collaboration of a state-level transp...

The Demand Responsive Connector (DRC) connects a residential area to a major transit network through a transfer point and is one of the most often adopted types of flexible transit services. In this paper, analytical and simulation models are developed to assist planners in the decision making process when having to choose between a demand responsi...

ADA paratransit systems are dial-a-ride services providing public transportation to disabled customers. In large metropolitan areas, these services might adopt zoning strategies to simplify their management. The objective of this research is to provide a more in-depth evaluation and comparison between centralized and decentralized zoning strategies...

Feeder lines are one of the most often used types of flexible transit services connecting a service area to a major transit network through a transfer point. They often switch operations between a demand responsive and a fixed-route policy. In designing and running such systems, the identification of the condition justifying the operating switch is...

Feeder transit services generally operate within residential service areas and move customers to and from a transfer point that connects to a major fixed-route transit network. Feeders can operate in a traditional fixed-route or in an emerging demand-responsive fashion. In designing such systems, planners may divide the entire service area into zon...

Public transport systems are confronted by the need to improve their economic effectiveness in order to meet customer requirements at acceptable costs for transit providers, which are often heavily subsidized. Our goal is to understand how the organizational form of the transit system impacts on system productivity. Our methodology consists of comp...

We study a hybrid transportation system referred to as Mobility Allowance Shuttle Transit (MAST) where vehicles may deviate from a fixed path consisting of a few mandatory checkpoints to serve demand distributed within a proper service area. In this paper we propose a Mixed Integer Programming (MIP) formulation for the static scheduling problem of...

In this paper we study the impact on productivity of specific operating practices currently used by demand responsive transit (DRT) providers. We investigate the effect of using a zoning vs. a no-zoning strategy and time-window settings on performance measures such as total trip miles, deadhead miles and fleet size. It is difficult to establish clo...

We study a hybrid transportation system referred to as mobility allowance shuttle transit (MAST) where vehicles may deviate from a fixed path consisting of a few mandatory checkpoints to serve demand distributed within a proper service area. In this paper we propose a mixed integer programming (MIP) formulation for the static scheduling problem of...

A Mobility Allowance Shuttle Transit (MAST) system is an innovative concept that merges the flexibility of Demand Responsive Transit (DRT) systems with the low cost operability of fixed-route bus systems. It allows vehicles to deviate from the fixed path so that customers within the service area may be picked up or dropped off at their desired loca...

The goal of this paper was to develop a performance measurement–based approach for transportation agencies, such as state departments of transportation, to evaluate and enhance sustainability. This research proposes a performance measurement–based framework and evaluation methodology for sustainable transportation, linked to agency strategic planni...

After September 11th, government officials have begun questioning the appropriateness of the current federal allocation formula to counter terrorism. Newly appointed Secretary Chertoff demanded the development of more rigorous risk-based mechanisms. This paper is one of the first addressing this request by developing the corresponding resource allo...

The environmental performance of public transport plays a key role in improving air quality in urban areas. An important way of improving existing transit services is to use innovative propulsive systems; however, this needs considerable financial resources that are not always available. Here we assess how the organizational form of the transit sys...

In this paper we develop an insertion heuristic for scheduling Mobility Allowance Shuttle Transit (MAST) services, an innovative concept that merges the flexibility of Demand Responsive Transit (DRT) systems with the low cost operability of fixed-route systems. A MAST system allows vehicles to deviate from the fixed path so that customers within a...

We develop bounds on the maximum longitudinal velocity to evaluate the performance and help the design of Mobility Allowance Shuttle Transit (MAST) services. MAST is a new concept in transportation that merges the flexibility of Demand Responsive Transit (DRT) systems with the low cost operability of fixed-route bus systems. A MAST system allows bu...

Thesis (Ph. D.)--University of Southern California, 2005. Includes bibliographical references (leaves 133-139). Microfiche.

The Mobility Allowance Shuttle Transit (MAST) system is an innovative concept that merges the flexibility of Demand Responsive Transit (DRT) systems with the low cost operability of fixed-route bus systems. A MAST service has a fixed base route that covers a specific geographic zone, with one or more mandatory checkpoints; the innovative twist is t...

In this paper, we develop an analytical model that aids decision-makers in designing a hybrid grid network that integrates a flexible demand responsive service with a fixed route service. The objective of the model is to determine the optimal number of zones in an area where each zone is served by a number of on-demand vehicles. The function of the...

The Mobility Allowance Shuttle Transit (MAST) system is an innovative concept that merges the flexibility of Demand Responsive Transit (DRT) systems with the low cost operability of fixed-route bus systems. A MAST service has a fixed base route that covers a specific geographic zone, with one or more mandatory checkpoints; the innovative twist is t...

The aim of this project was to develop a performance-measurement based approach for the Texas Department of Transportation (TxDOT) to evaluate and enhance the relative sustainability of transportation projects. TxDOT's strategic plan contains five goals (reduce congestion, improve safety, increase economic opportunity, preserve the value of transpo...