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DSpace at MIT (104.280 recursos)

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Ford-MIT Alliance

Mostrando recursos 1 - 10 de 10

  1. Beyond Health and Retirement: Placing Transportation on the Aging Policy Agenda

    Coughlin, Joseph F.
    The Hartford Financial Services Company and the Ford Motor Company

  2. Modeling Traffic Flow Emissions

    Cappiello, Alessandra
    The main topic of this thesis is the development of light-duty vehicle dynamic emission models and their integration with dynamic traffic models. Combined, these models constitute fundamental components to support the development and assessment of traffic management policies, and the optimization of their parameters, to alleviate the negative impacts of road traffic. We develop and implement a dynamic model of emissions (CO2, CO, HC, and NOx) and fuel consumption for light-duty vehicles. The model is derived from regression-based and load-based emissions modeling approaches, and effectively combines their respective advantages. The model is calibrated for two vehicle categories using FTP...

  3. Agents to the Rescue?

    West, Patricia M.; Ariely, Dan; Bellman, Steve; Bradlow, Eric; Huber, Joel; Johnson, Eric; Kahn, Barbara; Little, John; Schkade, David
    The advent of electronic environments is bound to have profound effects on consumer decision making. While the exact nature of these influences is only partially known it is clear that consumers could benefit from properly designed electronic agents that know individual users' preferences and can act on their behalf. An examination of the various roles agents perform is presented as a framework for thinking about the design of electronic agents. In addition, a set of goals is established that include both outcome-based measures, such as improving decision quality, as well as process measures like increasing satisfaction and developing trust.

  4. A Statistical Model of Vehicle Emissions and Fuel Consumption

    Cappiello, Alessandra; Chabini, Ismail; Nam, Edward K.; Lue, Alessandro; Zeid, Maya Abou
    A number of vehicle emission models are overly simple, such as static speed-dependent models widely used in practice, and other models are sophisticated as to require excessive inputs and calculations, which can slow down computational time. We develop and implement an instantaneous statistical model of emissions (CO2, CO, HC, and NOx) and fuel consumption for light-duty vehicles, which is derived from the physical loadbased approaches that are gaining in popularity. The model is calibrated for a set of vehicles driven on standard as well as aggressive driving cycles. The model is validated on another driving cycle in order to assess its estimation capabilities. The preliminary results...

  5. A Statistical Model of Vehicle Emissions and Fuel Consumption

    Cappiello, Alessandra; Chabini, Ismail; Lue, Alessandro; Zeid, Maya Abou; Nam, Edward K.
    Many vehicle emission models are overly simple, such as the speed dependent models used widely, and other models are sufficiently complicated as to require excessive inputs and calculations, which can slow down computational time. We develop and implement an instantaneous statistical model of emissions (CO2, CO, HC, and NOx) and fuel consumption for light-duty vehicles, which is simplified from the physical loadbased approaches that are gaining in popularity. The model is calibrated for a set of vehicles driven on standard as well as aggressive driving cycles. The model is validated on another driving cycle in order to test its estimation capabilities. The preliminary results indicate that the model gives reasonable results compared...

  6. Assessment of Rework Probabilities for Simulating Product Development Processes Using the Design Structure Matrix (DSM)

    Yassine, Ali A.; Whitney, Daniel E.; Zambito, Tony
    This paper uses the Design Structure Matrix (DSM) to model and simulate the performance of development processes. Though the simulation is a powerful tool for analyzing process performance, its ability is limited by the quality of input information used in the analysis. DSM simulation requires process data that is hard to assess or estimate directly from development participants. In this paper, we propose a methodology that allows a more practical estimation of an important simulation parameter: rework probabilities. Furthermore, we show how does this assessment method (combined with simulation) allow managers to evaluate process improvement plans based on two resulting process measures: reliability and robustness. The method is illustrated with a real application...

  7. Do-It-Right-First-Time (Draft) Approach To Design Structure Matrix (DSM) Restructuring

    Whitney, Daniel E.; Yassine, Ali A.; Lavine, Jerry; Zambito, Tony
    This paper argues, using two real-world applications from the automotive industry, that the biggest benefit of a Design Structure Matrix (DSM) model may come not from resequencing and partitioning, but rather from “rewiring” the process/blocks. “Rewiring” means redefining relationships among elements and/or inserting new elements into the matrix. This requires intimate understanding of the process and cannot be done with application of context-free partitioning algorithms. The Do-it-Right-First-Time (DRFT) approach to DSM restructuring is another way to look at a DSM by inspecting the sources of iteration within a block and reversing it through inserting a DRFT activity at the beginning of the block. In this way, the traditional Design-Build-Test “Cycle” is reversed into a...

  8. Performance of Coupled Product Development Activities with a Deadline

    Joglekar, Nitindra R.; Whitney, Daniel E.; Yassine, Ali A.; Eppinger, Steven D.
    This paper explores the performance of coupled development tasks subject to a deadline constraint by proposing a performance generation model (PGM). The goal of the PGM is to develop insights about optimal strategies (i.e. sequential, concurrent, or overlapped) to manage coupled design tasks that share fixed amount of engineering resources subject to performance and deadline constraints. Model analysis characterizes the solution space for the coupled development problem. The solution space is used to explore the generation of product performance and the associated dynamic forces affecting concurrent development practices. We use these forces to explain conditions under which concurrency is a desirable strategy.

  9. Analyzing Multiple Product Development Projects Based On Information and Resource Constraints

    Yassine, Ali; Browning, Tyson
    Product development (PD) and engineering design processes are often characterized by the information flowing among activities. In PD, this flow forms a complex activity web—a process that can be viewed as a complex system. Most literature on the subject of information flow in PD focuses on a single project, where precedence information constraints (based solely on necessary information and possible assumptions) determine the execution sequence for the activities and the resultant project lead-time. In this paper, we consider multiple PD projects that share a common set of design resources. Especially in this setting, precedence information availability is insufficient to assure that activities will execute on time. We...

  10. Precision Robot Calibration Using Kinematically Placed Inclinometers

    Robertson, Alec P.; Slocum, Alexander; Willoughby, Patrick J.
    In the field of industrial robotics, many different calibration methods exist to reduce error in the robot system. Locating the manipulator home position is a common calibration technique, which can be divided into three main categories — relative, optimal and leveling based methods. The home position of an industrial manipulator is a position where all joint angles have a pre-defined value (e.g. zero or 90 degrees), which can be transformed into Cartesian space via the robot kinematics. Large industrial manipulators, with a working range in the order of several meters, require an accurately defined home position that can be restored with repeatability in the order of 0.2mm...

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