Showing papers on "Fleet management published in 2008"

Transportation energy data book

Abstract: The Transportation Energy Data Book: Edition 11 is a statistical compendium prepared and published by Oak Ridge National Laboratory (ORNL) under contract with the Office of Transportation Technologies in the Department of Energy (DOE). Designed for use as a desk-top reference, the data book represents an assembly and display of statistics and information that characterize transportation activity, and presents data on other factors that influence transportation energy use. The purpose of this document is to present relevant statistical data in the form of tables and graphs. Each of the major transportation modes - highway, air, water, rail, pipeline - is treated in separate chapters or sections. Chapter 1 compares US transportation data with data from seven other countries. Aggregate energy use and energy supply data for all modes are presented in Chapter 2. The highway mode, which accounts for over three-fourths of total transportation energy consumption, is dealt with in Chapter 3. Topics in this chapter include automobiles, trucks, buses, fleet automobiles, federal standards, fuel economies, and household data. Chapter 4 is a new addition to the data book series, containing information on alternative fuels and alternatively-fueled vehicles. The last chapter, Chapter 5, covers each of the nonhighway modes: air,more » water, pipeline, and rail, respectively. 92 figs., 112 tabs.« less

An Optimization-Based Heuristic for the Split Delivery Vehicle Routing Problem

Abstract: The split delivery vehicle routing problem is concerned with serving the demand of a set of customers with a fleet of capacitated vehicles at minimum cost. Contrary to what is assumed in the classical vehicle routing problem, a customer can be served by more than one vehicle, if convenient. We present a solution approach that integrates heuristic search with optimization by using an integer program to explore promising parts of the search space identified by a tabu search heuristic. Computational results show that the method improves the solution of the tabu search in all but one instance of a large test set.

An approach to specification-based attack detection for in-vehicle networks

Abstract: An upcoming trend for automotive manufacturers is to create seamless interaction between a vehicle and fleet management to provide remote diagnostics and firmware updates over the air. To allow this, the previously isolated in-vehicle network must be connected to an external network, and can thus be exposed to a whole new range of threats known as cyber attacks. In this paper we explore the applicability of a specification-based approach to detect cyber attacks within the in-vehicle network. We derive information to create security specifications for communication and ECU behavior from the CANopen draft standard 3.01 communication protocol and object directory sections. We also provide a set of example specifications, propose a suitable location for the attack detector, and evaluate the detection using a set of attack actions.

Planning local container drayage operations given a port access appointment system

Abstract: This paper studies the management of a fleet of trucks providing container pickup and delivery service (drayage) to a port with an appointment-based access control system. Responding to growing access congestion and its resultant impacts, many US port terminals have implemented appointment systems, but little is known about the potential impact of such systems on drayage fleet efficiency. To address this knowledge gap, we develop a drayage operations planning approach based on an integer programming heuristic that explicitly models a port access control system. The approach determines pickup and delivery sequences for daily drayage operations with minimum transportation cost. We use the framework to develop an understanding of the potential productivity impacts of access control systems on drayage firms. Most importantly, we find that it is critical for terminal operators to provide enough access capacity for drayage, since vehicle productivity can be increased by 10–24% when total access capacity is increased by 30%. Furthermore, poor (but not unreasonable) selection of access appointment time slots by drayage firms may result in substantial customer service deficiencies, reducing the number of customers that can be served by up to 4% for a fixed level of total access capacity.

Next-Generation Automated Vehicle Location Systems: Positioning at the Lane Level

Abstract: The majority of today's automated vehicle location (AVL) systems use Global Positioning System (GPS) technology, which can provide position information with an accuracy of approximately 15 m. Recently, low-cost Differential GPS (DGPS) receivers, which have a positioning accuracy of approximate 2-3 m, have become available. With this increased accuracy, it is now possible to perform AVL down to specific roadway lanes. In this paper, a vehicle-lane-determining system is described, consisting of an onboard DGPS receiver that is connected with a wireless communications channel, a unique lane-level digital roadway database, a developed lane-matching algorithm, and a real-time vehicle location display. Lane-level positioning opens up the door for a number of new intelligent transportation system applications such as better fleet management, lane-based traffic measurements from probe vehicles, and lane-level navigation. The developed low-cost system has been tested on a number of roadways and has performed very well when used with accurately surveyed map data. Based on more than 100 000 s, it has correctly determined the lane 97% of the time.

Real-time tracking management system using GPS, GPRS and Google earth

Abstract: Due to the high cost of fossil-based energy, several methods are proposed to reduce the usage of the energy in logistics and fleet management to be even more. GPS tracking system is a common approach to get vehicle location information in real-time for fleet planning. We proposed a GPS tracking system called Goo-Tracking that is composed of commodity hardware, open source software and an easy-to-manage user interface via a Web server with Google Map or via Google Earth software. The system includes a GPS/GPRS module to location acquisition and message transmission, MMC to temporary store location information, and an 8-bit AVR microcontroller. Our system prototype is shown and tested on a trip from Bangkok to Chonburi. It has shown great stability and also robust message transfer protocol that most of locations are accurately acquired and transmitted to the server in real-time.

Carsharing: Dynamic Decision-Making Problem for Vehicle Allocation

Abstract: Carsharing provides members access to a fleet of shared-use vehicles in a network of locations on a short-term, as-needed basis. It allows individuals to gain the benefits of private vehicle use without the costs and responsibilities of ownership. The dynamic vehicle allocation problem is addressed in a carsharing context, that is, as a decision-making problem for vehicle fleet management in both time and space to maximize profits for the carsharing service operator. A multistage stochastic linear integer model with recourse is formulated that can account for system uncertainties such as carsharing demand variation. A stochastic optimization method based on Monte Carlo sampling is proposed to solve the carsharing dynamic vehicle allocation problem. Preliminary results are discussed and related insights are presented on the basis of a five-stage experimental network pilot study.

Simulated attacks on CAN buses: vehicle virus

Abstract: Contemporary vehicles contain a number of electronic control units (ECUs), which are connected in a network and provide various vehicle functionalities. The firmware on the ECUs need to be kept up-to-date to provide better and safer functionalities. An upcoming trend for automotive manufacturers is to create seamless interaction between the vehicle and fleet management to provide remote diagnostics and firmware updates over the air. To allow this, the previously isolated in-vehicle network must connect to an external network, and is thus exposed to a whole new range of threats, collectively known as cyber attacks. In this paper we have evaluated the ability of the current in-vehicle network to withstand cyber attacks by simulating a set of plausible attacks targeting the ECUs on the CAN bus. The results show that the network lacks sufficient protection against these attacks, and we therefore extensively discuss the future security needs for preventing, detecting, countering and recovering from such attacks.

Multiple objective optimization of the fleet sizing problem for road freight transportation

Abstract: A fleet sizing problem (FSP) in a road freight transportation company with heterogeneous fleet and its own technical back-up facilities is considered in the paper. The mathematical model of the decision problem is formulated in terms of multiple objective mathematical programming based on queuing theory. Technical and economical criteria as well as interests of different stakeholders are taken into account in the problem formulation. The solution procedure is composed of two steps. In the first one a sample of Pareto-optimal solutions is generated by an original program called MEGROS. In the second step this set is reviewed and evaluated, according to the Decision Maker's (DM's) model of preferences. The evaluation of solutions is carried out with an application of an interactive multiple criteria analysis method, called Light Beam Search (LBS). Finally, the DM selects the most desirable, compromise solution.

Optimal operations of transportation fleet for unloading activities at container ports

Abstract: This paper presents mathematical models that optimize the size of transportation fleet (cranes and trucks) for unloading operations at container terminals. A cyclic queue model is used to study the steady-state port throughput, which then yields the optimum fleet size for long-term operations. This model allows for stochastic operations such as exponentially distributed crane service times. In order to allow for generally distributed crane service times and truck travel times, an approach based on Markovian decision process is also proposed. This model provides dynamic operational policies for fleet management. Both models are implemented and examined with empirical data from the Port of Balboa, Panama. These models are also extended to unloading operations that involve multiple berths.

Petrol delivery tanker assignment and routing: a case study in Hong Kong

Abstract: In this paper, we present a case study on a tanker assignment and routing problem for petrol products in Hong Kong. A fleet of heterogeneous dangerous goods vehicles has been assigned to deliver several types of petroleum products to petrol stations with different tank capacities. Under the vendor-managed inventory system, the delivery company is responsible for controlling the station's inventory and replenishment. The operational characteristics and challenges such as geographic zoning, size of petrol stations, routing restrictions and so on are unique and have been described in this paper. A decision support system (DSS) combining heuristic clustering and optimal routing is employed to find the optimal fleet assignment and routing. Multiple objectives are considered simultaneously such that the number of tankers used could be minimized, the number of drops in trips is minimized, profit in terms of total products delivered is maximized and utilization of resources is maximized. The case illustrates the benefit and advantages of using the proposed DSS.

Dynamic travel time provision for road networks

Abstract: The application domain of intelligent transportation is plagued by a shortage of data sources that adequately assess traffic situations. Typically, to provide routing and navigation solutions map attributes in the form of static weights as derived from road categories and speed limits used for road networks. With the advent of Floating Car Data (FCD) and specifically the GPS-based tracking data component, a means was found to derive accurate and up-to-date travel times, i.e., qualitative traffic information. FCD is a by-product in fleet management applications and given a minimum number and uniform distribution of vehicles, this data can be used for accurate traffic assessment and also prediction. This work showcases a system that facilitates the collection of FCD, produces dynamic travel time information, and provides value-added services based on the dynamic travel times. The essential components that will be discussed are a Web-services-based data collection approach, sophisticated map-matching algorithms, a data management architecture and an online visualization platform.

Route Design for Lean Production Systems

Abstract: We consider the problem of routing a fleet of vehicles to pick up components from a network of suppliers and to deliver them to a fixed depot in a lean production system. The pursuit of low work-in-process inventory and production smoothing throughout the system introduces complicating side constraints, creating an enriched case of the vehicle routing problem with time windows and split deliveries. We present a two-phase routing and scheduling approach to address this problem. The routing phase consists of a nested tabu search heuristic that iterates between determining the suppliers' visit frequencies and developing vehicle routes. Given a routing plan, the scheduling phase determines the timing of supplier visits using a binary integer program designed to promote production leveling. Through computational testing on real-world data sets, we compare our solutions to those in the literature and those used by practitioners in the industry.

Queuing Models for Sizing and Structuring Rental Fleets

Abstract: This paper has been motivated by a fleet optimization problem faced by one of the leading European cargo rail companies. The company operates a fleet of more than 100,000 rail cars and annually invests significant sums of money into new cars. Because the price tag of a new car is over 50,000 euros, planning such a fleet is an important activity at the company. In this paper, we develop and solve analytical models for fleet planning. We first describe the rental process and show how it can be modeled as a queuing loss system. We then develop a profit function and derive several structural results, such as the concavity of the profit function in the fleet size. Building on these structural results, we show how the fleet size can be optimized, how the fleet structure (i.e., the types of cars being used) can be optimized, and how a joint fleet of owned and leased cars can be optimized. Because some of the optimal methods are difficult to implement, we also develop and test an approximation that is easy to implement. To illustrate our findings and to validate our approach, we provide numerical results that are based on data of the company that motivated our research.

The way ahead for London's bus priority at traffic signals

Abstract: London has a long history of successful schemes for bus priority at traffic signals. Recently, Transport for London (TfL) has procured a modern automatic vehicle location (AVL) system for bus fleet management, passenger information and bus priority. The new system is known as iBUS and is based on global positioning system (GPS) and supporting technologies for bus location. The system eliminates the need for on-street hardware for detecting buses and provides more flexibility and opportunity for using bus detectors. However, bus location based on this system is less accurate than location based on fixed infrastructure (e.g. beacons) and could result in reduced benefits from bus priority. This paper first summarises how bus priority at traffic signals works within iBUS, and then explores the effects of GPS locational errors on bus priority benefits. This is followed by a discussion of opportunities available in the context of iBUS to build an even more efficient and beneficial bus priority system by taking advantage of its cost-effective multiple detection capabilities. The paper is based on various studies carried out by the Transportation Research Group (TRG) at the University of Southampton for TfL.

Methods and systems for secure keyless entry for vehicle fleet management

Abstract: The technology described herein provides a keyless entry system and associated method for fleet vehicle management. Secure keyless entry is provided to a user for a vehicle in the fleet vehicle management environment without the user having possession of a vehicle key or a vehicle key fob to gain entry to the vehicle. Additionally, in various embodiments, this technology provides a personalized, programmable access device carried by a user desiring access to a particular locked vehicle in a fleet vehicle management environment, an access control device configured to access electronically an on-board vehicle keyless entry system, and an access chip module electronically attached to the access control device and configured to activate the on-board vehicle keyless entry system and thereby unlock the particular locked vehicle. Furthermore, this technology provides a system with local management, reporting, audit trails, wireless connectivity to each access control device, and self-testing.

Ontologies and agents for a bus fleet management system

Abstract: This paper reports on the design and implementation of a multi-agent decision support system for the bus fleet management domain. In particular, we show a complete description of the proposed multi-agent architecture and focus mainly on knowledge and software engineering features. The system has been developed in collaboration with the Malaga urban bus company (EMT) and it is based on a faithful reproduction of the real operating conditions of three existing lines of this company.

Towards an integrated perspective on fleet asset management: engineering and governance considerations

Abstract: The traditional engineering perspective on asset management concentrates on the operational performance the assets. This perspective aims at managing assets through their life-cycle, from technical specification, to acquisition, operation including maintenance, and disposal. However, the engineering perspective often takes for granted organizational-level factors. For example, a focus on performance at the asset level may lead to ignore performance measures at the business unit level. The governance perspective on asset management usually concentrates on organizational factors, and measures performance in financial terms. In doing so, the governance perspective tends to ignore the engineering considerations required for optimal asset performance. These two perspectives often take each other for granted. However experience demonstrates that an exclusive focus on one or the other may lead to sub-optimal performance. For example, the two perspectives have different time frames: engineering considers the long term asset life-cycle whereas the organizational time frame is based on a yearly financial calendar. Asset fleets provide a relevant and important context to investigate the interaction between engineering and governance views on asset management as fleets have distributed system characteristics. In this project we investigate how engineering and governance perspectives can be reconciled and integrated to enable optimal asset and organizational performance in the context of asset fleets.

System for managing a fleet of motor vehicles accessible via a storage key and method for managing the corresponding fleet

Abstract: The invention relates to a system for managing a fleet of motor vehicles, comprising a central platform (1) which can store data for the management of the fleet and an interface (6) located remotely from the vehicle, enabling communication between a driver and the central platform (1). Each vehicle of the fleet can be accessed via a storage key (10) which can store data relating to the identification and operation of the vehicle, as well as data relating to the fleet management contract, and which can be used to manage the engine start-up/engine immobilisation and locking/unlocking functions of the vehicle. Each key can be activated and released by the central platform (1) at the user's request via the above-mentioned remote interface that can communicate with the central platform.

Tactical Locomotive Fleet Sizing for Freight Train Operations

Abstract: Determination of fleet size of locomotives and of a policy to deadhead them are tactical issues that influence the level of customer service in a rail network. This paper considers a railroad system in which a priori freight train schedule does not exist. A simulation-based approach is proposed for tactical locomotive fleet sizing. The study shows that the throughput increases with the number of locomotives upto a certain level; after that the congestion caused by the movements of large number of locomotives in the capacity-constrained rail network offsets the potential benefit of a large fleet.

An analysis on long term emission benefits of a government vehicle fleet replacement plan in northern illinois

Abstract: There have been a number of studies of the effectiveness of vehicle scrappage programs, which offer incentives to accelerated scrappage of older vehicles often thought to be high emitters. These programs are voluntary and aimed at replacement of household vehicles. In contrast, there is a gap in knowledge related to the emissions benefits of government fleet replacement (retirement) programs. In this study, the efficacy of a fleet replacement program for a local government agency in Northern Illinois, the Forest Preserve of DuPage County (FPDC), is examined using a probabilistic vehicle survival model that accounts for time-varying covariates such as vehicle age and gasoline price. The vehicle lifetime operating emissions are calculated based on the estimated vehicle survival probabilities from the survival model and compared with those derived using the EPA default fleet used in MOBILE6 and the fleet represented by the Oak Ridge National Laboratory (ORNL) survival curve. The results suggest that while there may be short term emission benefits of the FPDC fleet replacement plan, the long-term emission benefits are highly sensitive to economic factors (e.g., future gasoline price) and exhibit a decreasing trend. This indicates that an adaptive multi-stage replacement strategy as opposed to a fixed one is preferable to achieve optimal cost effectiveness.

Approximate dynamic programming: lessons from the field

Abstract: Approximate dynamic programming is emerging as a powerful tool for certain classes of multistage stochastic, dynamic problems that arise in operations research. It has been applied to a wide range of problems spanning complex financial management problems, dynamic routing and scheduling, machine scheduling, energy management, health resource management, and very large-scale fleet management problems. It offers a modeling framework that is extremely flexible, making it possible to combine the strengths of simulation with the intelligence of optimization. Yet it remains a sometimes frustrating algorithmic strategy which requires considerable intuition into the structure of a problem. There are a number of algorithmic choices that have to be made in the design of a complete ADP algorithm. This tutorial describes the author?s experiences with many of these choices in the course of solving a wide range of problems.

Asset management and governance — An analysis of fleet management process issues in an asset-intensive organization

Abstract: Efficient asset management is a key performance driver for asset-intensive organizations Achieving high utilization and return on investment on physical assets are central corporate objectives for public and private organisations alike Current approaches on asset management include the engineering and governance perspectives The engineering perspective on asset management concentrates on the technical and operational dimensions of asset performance, including utilization, and operation to technical specifications However, this perspective often ignores organisational-level factors that potentially affect asset performance By contrast, from a governance perspective, key factors influencing asset management performance include stewardship, accountability and incentive regimes Symmetrically, the governance view often takes the operational factors for granted In sum, both perspectives offer valuable but incomplete insights on the management of asset performance: experience demonstrates that an exclusive focus on one or the other may lead to sub-optimal asset and organizational performance In this paper, we investigate how an integrated approach to asset management can be constructed in the context of vehicle fleets Vehicle fleets provide a suitable context to investigate these issues as they constitute significant investments, and are observable across a range of asset-intensive industries Beginning with an analysis of how the asset management process is operated through the asset lifecycle, we identify key engineering and organizational factors influencing asset performance The relationships between factors are analyzed to provide an integrated fleet asset management approach

Continuous-time dynamic network yield management with demand driven dispatch in the airline industry

Abstract: This study integrates the airlines dynamic network yield management and demand driven dispatch. In this problem, the final fleet assignment is determined by the accepted bookings. The objective is to develop a policy for acceptance/rejection of booking requests to maximize the total expected revenue less operational cost. This paper simultaneously makes optimal dynamic yield management and fleet assignment decisions. In addition, it investigates a special popular practical instance in North America in which the a priori fleet assignment imbeds aircraft swap opportunities. An approximate dynamic method is specially proposed for it, and numerical results demonstrate its strong applicability.

Development and Evaluation of an Intelligent Fleet Management System for City Logistics

Abstract: The routing plan of a delivery fleet is usually developed a priori and provides an optimal (or near optimal) way of serving customers by taking into account certain constraints, such as delivery time windows. However, such plans may not cope adequately with the dynamics of a city logistics environment, in which unexpected events (e.g. traffic congestions) often occur during delivery execution. We present the development and evaluation of a real-time fleet management system that handles such unforeseen events. The system monitors the delivery vehicles in real time, detects deviations from the initial distribution plan, and adjusts the schedule accordingly by suggesting effective rerouting strategies. The system has been tested in simulation environment and in real-life cases and the results show that delivery performance is enhanced significantly and customer satisfaction is improved.

Introducing the Next Generation Locomotive to the Australian Rail Network

Abstract: The following paper describes the introduction of what IS now the most powerful and efficient locomotive operating across Australia's Defined Interstate Rail Network. The locomotive was originally conceived by SCT Logistics after analysing the market and commissioning a study from Halcrow to determine motive power configurations that would best SUlI their expanding rail business. The designer and manufacturer of the SCT locomotive designated the GT46C Ace, is Downer EDI Rail. The paper gives an insight into how the locomotive was conceived, including the planning and modelling that determined SCT's decision for choosing AC traction and the associated cost benefit analyses. Also discussed are the risks considered by SCT in taking ownership of their own fleet with technology which supersedes present locomotive fleets operating across Australia's mainline rail networks. The paper details the Innovative solutions provided by Downer EDI Rail in engineering and manufacturing a locomotive to meet SCT's demanding requirements for operation and those of the State Regulators and track access providers. The paper concludes by comparing the operating performance of the new locomotive with the operator's expectations.

Compilation and distribution of data for aircraft fleet management

Abstract: A fleet management service receives HUMS data from a multitude of operators, compiles the HUMS data, and communicates fleet management data to each of the multiple of operators as compared to a fleet of that aircraft type. The fleet management service provides an executive level summary of each operator's aircraft, maintenance and supply chain performance, with analysis of this performance compared to the fleet of that aircraft type.