Tepper School of Business

Logistics costs control has always been considered a key issue for business development. In order to decrease transportation costs, companies are pushed to negotiate lower logistic service prices with Third-Party Logistics Service Providers (3PL) which, in turn, should be able to optimize their processes and reduce their costs in order to preserve the adequate profitability and allow their industrial customers to gain competitive advantage. In this paper a method to reduce industrial costs and negative externalities associated with fleet management on an Hub & Spoke transportation network is presented. We state that the Time Dependent VRP with Pick-up and Deliveries and Time Windows model may be the most suitable for goods distribution problem inside large cities. A dynamic version capable to consider road traffic along with variable congestion effects during the day has been created. Hence, we proposed a quick and flexible heuristic that has been validated with the real data of a subsidiary of a 3PL leader in the express transportation sector. The heuristic has demonstrated to be able to reduce travel time, travelled distance and, at the same time, significantly increase the service level, on top of the relative benefit for the community coming from a substantial reduction of air pollution, noise pollution, congestion and incidentally.

Due to rapid population growth, unavailability of resources and climate changes, energy saving has become of great interest especially during the last 30 years. One of the most evident human activities weighing down on pollution and energy consumption is the construction of residential buildings. However, the construction phase is but one of the stages in wasting resources. In fact, once a residential settlement has been built, it is time for the dweller to use up resources. In our work, we propose an analysis of the socio-technical mechanisms which move people towards energy efficiency and the technology innovation that make it possible. We will then describe the model structure and the various leverages that the users are able to handle during the innovation process. Finally, a discussion of results and implications for future research will also be provided.

The transportation sector is one of the most resilient to the shift away from oil. Policies have been put in place in different regions to introduce alternative fuels and reduce the road transportation heavy dependency on oil products and the related environmental impacts; results, however, are in most cases disappointing. The system is resilient and goes back to the historical dichotomy gasoline-diesel. If from a policy maker perspective, a system dynamics model of the automotive sector can lead to the development of effective policies to achieve sustainable mobility, from an energy company perspective, such a model could be used to analyze possible threats and design optimal adaptation strategies for a highly volatile and market that is always on the edge of starting a new major transition. The model here presented can serve both purposes, and the results obtained show how a similar instrument can really make the difference in highly dynamic sectors with ongoing major transitions.

We focus on the problem of designing a supply chain for a new product. We propose a stochastic dynamic program based on a Stochastic Bass Model of the product demand dynamics. We heuristically solve our model using Monte Carlo simulation and math programming techniques. We apply our approach to the case of a new distribution service for Made-in-Italy wine and food products, benchmarking the performance of our heuristic policy against the performance of an easier to compute heuristic policy and a lower bound.

Saaty's AHP is helpful in evaluating alternatives thanks to its effective procedure to determine the relative weights of several comparison criteria. Combining the results of expert interviews, AHP can be very useful for a company in choosing a third party logistics service provider (3PL). However, in the traditional AHP procedure, several results may be rejected when the consistency ratio (CR) of the respondent exceeds a certain threshold. As a consequence, AHP interviews may be repeated several times with a consequent waste of time. In many industrial domains, a faster way to choose a supplier would thus be appreciated. In this paper we propose a mathematical method that combines AHP, DEA and linear programming in order to support the multi-criteria evaluation of third party logistics service providers. The proposed model aims to overcome the limitation of the AHP method, merging experts’ indications with objective judgments which originate from historical data analysis. Suppliers' past performance is thus used to correct eventual errors resulting from the acceptance of interviews where the consistency ratio is high. The proposed model has been validated on the real case of an international logistics service provider.

The paper deepen the analysis into the Virtual Safety Stock theory, which is an approach intended to drastically reduce safety inventory levels exploiting the eventual time lag between the moment when a product is ordered and the time the product needs to be available, while preserving the same performance as a production system that operates with physical safety stock. The original virtual safety stock definition embeds two major problems: a double Gaussian integral in the formulation together with the heritage of the unrealistic assumptions already included in the earliest Hadley and Whitin's safety stock conception. This paper describes an alternative approach in which the virtual safety stock is defined with a closed-form expression much easier to compute and use in operations management practice.

Traditional project management models based on the Critical Path Method (CPM) and PERT (Moder et al. 1983; Halpin and Woodhead 1980) provides several tools for trading away good performance in one measure for improved performance in another. For example durations of activities along the critical path can be shortened by adding more resources (Ulrich and Eppinger, 1994;. The effects of altering activity dependencies among activities to shorten the critical path can be investigated . These methods are limited by their use of an indirect project measure (time) and by bundling the characteristics of and relationships among scope, resources, and processes in each activity into a single duration ("Tor Vergata

While existing research has mainly focused on project management's static view, our work investigates the impacts of projects' structure and behavioural dynamics on their performance, with a specific focus on the influence of some peculiar development processes. A dynamic simulation model of a single-phase project was built using the system dynamics methodology. The model integrates several previously developed and tested project structures and adds a separate structure for the negotiation process. Simulations describe the behaviours generated by the interaction of customized development processes in single-phase projects. Project performances are measured in terms of time, quality and cost. Our research aims to show that development processes, as well as shared resource levelling techniques, significantly impact the dynamic behaviour of projects through the feedback, delays and nonlinear relationships which are usually omitted in traditional project management practice, as well as in methods, tools and models, but are very important descriptors of project complexity. Expanding the models used to manage projects to include dynamic features requires a change of focus by researchers and practitioners. The system dynamics methodology provides some of the tools for developing and implementing such an expansion in project models.

In the AHP procedure, experts are asked to provide a numerical quantification in pair-wise comparisons; when dealing with several criteria, inconsistency may rise and Saaty's Consistency Ratio threshold helps in identifying those matrices to be rejected or those interviews to be repeated. However, in certain domains, a faster way to proceed in the determination of the criteria weight is appreciated, along with the opportunity of merging the experts' indications with objective judgments originating from historical data analysis. This is the case of several industrial firms which have to perform a supplier selection. In this paper, we propose an evaluation method that combines AHP, DEA and Linear Programming in order to support multi-criterion decisions of Third Party Logistics providers: a rewarding/penalizing effect, depending on the suppliers past performance, is used to correct the errors resulting from biased quantification of weights in AHP. The proposed model has been validated on the real case of an international Logistics Service Provider.

Supply Chain Network Design (SCND) deals with the determination of the physical configuration and infrastructures of the supply chain. Specifically, facility location is one of the most critical decisions: transportation, inventory and information sharing decisions can be readily re-optimized in response to changes in the context, while facility location is often fixed and

This paper addresses the problem of designing a depannage service network for freight transportation fleets in order to fill up an evident gap in Operations Management literature. As a matter of fact, breakdowns have a significant impact on service level and an efficient and effective assistance service is needed in order to guarantee competitive advantage. Aiming at laying the foundations for further research on modelling and solving the considered problem, a literature review is performed for identifying analogies with other ...

For many organizations, a key issue at the intersection of strategy, change, and culture is
sustainability--meeting current environmental and social needs without jeopardizing future
generations’ ability to meet those same needs. The level of commitment to sustainability as
communicated in both a firm’s sustainability reports and its social media activity (e.g.,
Facebook, Twitter) may yield important insights into the values underlying the firm’s culture.
This exploratory study seeks to examine whether cultures supporting one form of innovation—
sustainability--will also support another type of innovation--social media. Data are compared
from a sample of eleven global, public firms in an industry with clear links to “green” practices
(manufacturing of household cleaning products). The variables are study are drawn from
corporate sustainability reports, social media venues, and rankings by external organizations and
Board diversity (as proxies for measuring organizational culture). Results suggest variation
across firms in their commitment to sustainability practices, as well as preliminary support for a
link between communicating sustainability, social media, and cultural values. Outcomes and
implications are discussed, including recommendations for organizations seeking to implement
sustainability initiatives.

Abstract Organizations increasingly rely on teams to formulate plans and respond in critical situations. However, current models of team process are insensitive to the effects of team strategic orientation. This paper expands existing work on team process and strategic orientation to introduce and explicate the constructs of offensive and defensive strategic orientations in teams.

Abstract Organizations use multiple team membership to enhance individual and team productivity and learning, but this structure creates competing pressures on attention and information, which make it difficult to increase both productivity and learning. Our model describes how the number and variety of multiple team memberships drive different mechanisms, yielding distinct effects. We show how carefully balancing the number and variety of team memberships can enhance both productivity and learning.

There is a long tradition of research on work in teams and their increasingly important use as an approach to organizational design. While the implicit assumption has been that individuals work on one team at a time, many individuals are now being asked to juggle several projects and their associated multiple team memberships (MTM) simultaneously. This creates a set of interesting opportunities and challenges for organizations that choose to structure work in this way.

Abstract This research investigates the effect of members 'object and spatial visualization cognitive styles—a deep-level diversity variable previously unexplored in the groups literature—on team processes and performance. Study 1 establishes that teams composed of spatial visualizers are more process-focused than teams of object visualizers; process focus affects team performance.

As defined in Chapter 1 of this volume,“An MTS constitutes subsets of component teams acting interdependently to accomplish at least one proximal goal, with all acting in concert toward a superordinate distal goal.” Interdependence in MTSs can be in terms of inputs, process, and outputs. The inputs may include human, informational, technological, material, and financial resources. Other chapters in this book address the informational, technological, material, and financial interdependence.

METHOD Eight teams, four “Red”(offense) and four “Blue”(defense) participated in pairs in four different week-long interagency task forces between January, 2005 and April, 2007. Each team involved 5-8 experienced intelligence analysts. All teams worked on known current threats, and exactly the same input data was provided to both the Red and Blue teams in each case. Each team was audio-and video-taped for the duration of their week-long collaboration, yielding approx.

Abstract The well-established dissociation between the ventral object and dorsal spatial processing streams within the visual system suggests a contrast between object and spatial visual cognitive styles. We assessed the validity of this distinction using a self-report questionnaire in a sample of 3839 online participants, and laboratory cognitive tests in a subsample of 196. We found that (1) object and spatial processing preferences were virtually uncorrelated (r=–.

Abstract The well-established dissociation between the ventral object and dorsal spatial processing streams within the visual system suggests a contrast between object and spatial visual cognitive styles. We assessed the validity of this distinction using a self-report questionnaire in a sample of 3839 online participants, and laboratory cognitive tests in a subsample of 196. We found that (1) object and spatial processing preferences were virtually uncorrelated (r=–.