- Email: [email protected]
Adoption of telecommuting: Modeling the employer's and the employee's decision processes
Recent doctoral dissertations traffic. The empirical analysis on trip time and reliability for different groups of traffic showed that railroads are currently differentiating services for major classes of traffic. Second, the research developed insights into the effects of service differentiation on the service provided to segmented markets and on the costs to railroads of providing such differentiated services. Two simulation analyses showed that service differentiation strategies enable a railroad to provide market-sensitive services, to more efficiently utilize service capacity, and to potentially enhance profit. Third, the research examined how to further improve the ability of a railroad to differentiate services by designing an operating plan that considers the heterogeneity of shippers and their traffic. A dynamic freight car routing and scheduling model was developed as a practical decision support tool. The results of the case study showed that the dynamic car routing and scheduling model can effectively allow a railroad to plan clearly differentiated services for heterogeneous shippers and their traffic. (Copies available exclusively from MIT Libraries. Rm. 14-0551, Cambridge, MA 021394307. Ph. 617-253-5668: Fax 617-253-1690.)
Optimisation of train schedules to minim& transit time and maximise reliability. Higgins, Andrew, Ph.D. Queensland University of Technology. 1996. 260 pp. (Available from Inter-library loans, Gardens
Point Campus, Queensland University of Technology, P.O. Box 2434. Brisbane 400 1, Australia). This research deals with the scheduling of trains on single track corridors to minimize train trip times and maximize reliability of train arrival times. A method to quantify the amount of risk of delay associated with each train, each track segment. and the schedule as a whole is advanced and used as the reliability component of the constrained optimization model. The risk-of-delay mode1 can also be applied to the ranking of investment projects designed to improve timetable reliability. Comparisons can be made between track, terminal and rolling stock projects in terms of their likely impact on timetable reliability. A number of solution techniques for the scheduling problem are described. New lower bounds for the branch and bound technique are presented which allow solutions for reasonable size train scheduling problems to be efficiently determined. Three solution heuristic techniques are applied to the train scheduling problem: a local search heuristic with an improved neighborhood structure, genetic algorithms with an efficient string representation, and tabu search. The heuristic and branch and bound techniques are compared in terms of number of calculations and solution quality. The branch and bound technique with the best lower bound out-performed genetic algorithms and tabu search for all except the largest problems. The model and solution techniques are applied to the problem of modeling the number and location of sidings on a single track corridor. with respect to a given schedule. A decomposition procedure is used
71
to partition the model into easily solvable submodels. The procedure converged quickly, and numerical results indicate savings in terms of train trip times and schedule reliability when track sid-
ings are at improved positions. The train scheduling model and solution techniques are then applied to an actual track corridor. The optimal train schedule is found to have considerably less delay due to conflicts than the schedule as resolved by rail operations planners.
Railway-caused road traffic in catchment areas of stations. Brocke, Delia, Dip].-Ing. Universitdt Karlsruhe (Germany). 1995. 177 pp. (in German).
This dissertation deals with the travel behavior of passengers who are accessing or leaving a rail station. It examines the sequence of all modes of transport taken to reach the station, as well as the respective access times. Then, a special analysis of the routes used by railway passengers to get to the station on the road is conducted. Interviews at the central stations of Karlsruhe and Stuttgart were used to collect empirical data. On the basis of origins and destinations. the station’s catchment areas are derived from specially-developed delimitation criteria. These catchment areas are extremely large as illustrated by the long access times. The number of road vehicles which serve interviewees as feeders to the station is extrapolated to the number of vehicles used for access and departure by all tail passengers. This railway-caused road traffic can be set into a ratio to the total traffic on the roads in the catchment areas by which the so-called “road using rates” are obtained. They are differentiated between “section-related” and “area-related” roads using rates either for single road sections or for specified reference areas. The determined values of the road using rates are found to be exceedingly low. It can be concluded that the volume of the railway-caused road traffic is minimal in comparison to the total road traffic and that consequently the railway passengers’ vehicles do not produce substantial additional traffic on the roads.
TELECOMMUNICATIONS/ TRANSPORTATION RELATIONSHIPS Adoption of telecommuting: Modeling the employer’s and the employee’s decision processes. Bernardino, Adriana Teixeira, Ph.D. Massachusetts Institute of Technolog_v. 1995. Supervisor: Moshe Ben-Akiva.
This research develops a comprehensive model of the telecommuting adoption process, incorporating both the employer’s and the employee’s perspectives. A probabilistic modeling approach is taken. The employer’s decision to offer a telecommuting program to his/her employees is modeled as a function of his/her motivations and constraints. and of the perceived impacts of telecommuting on the organization’s productivity and
72
Recent doctoral dissertations
costs. The employee’s decision to adopt an available telecommuting program is modeled as a function of his/her motivations and constraints, as well as of the impacts of the available program on lifestyle quality, work-related costs and income. The results indicate that telecommuting has significant potential to increase productivity and improve lifestyle quality, if the right program is designed for the right employee. The potential of telecommuting to reduce organizational and employee work-related costs is perceived to be limited. A generally negative perception about the potential impacts of telework-center based telecommuting programs on productivity and lifestyle quality is identified. Telecommuting has a significant potential to reduce work trips, and that this potential can be further enhanced as experience with such arrangements increases. These results indicate that a positive experience with telecommuting can increasing the level of adoption. (Copies available exclusively from MIT Libraries, RM. 14-0551, Cambridge, MA 021394307. Ph. 617-253-5668; Fax 617-253-1690.)
Trattsportation and telecommunications: Potential interactions between physical and immaterial [virtual] travel. Divieti, Laura, Ph.D. University of Trieste (Italy), 1995. 146 pp. Chairman: Claudio Podesta.
Information-based alternatives to travel have led to the concept of the transportation system and the telecommunication network as an integrated teletrans (telecommunications-transportation) network. With innovative telecommunications technologies, it is now possible to move instantly from one place to another, accessing information in real-time, virtually eliminating travel distance and time. In the long-term, we expect that various activities (e.g., work, shopping, leisure and so on) will be differentially affected by the electronicallybased ‘no-travel’ option. Availability of telecommunications does not necessarily imply that users will always choose the no-travel option, but it will clearly change the choice set and decision-making process. A preliminary modeling framework to evaluate the teletrans concept is presented by means of a probabilistic approach (random utility model). An empirical survey, carried out to validate the proposed model, highlighted the influence of personal attitudes on the perception of various options. Telematic applications will be evaluated by potential users from an individual viewpoint (e.g., physical and social isolation, conflicts between private and working life) and an organizational viewpoint (e.g., management control, issues related to information access, implementation costs, etc.). The communication contexts (e.g. purpose, urgency, value and complexity); the ease of use and reliability of telematic equipment; and increasing congestion, time lost to travel, and stress will also play a role.
Transportation/communications relationships in the European community. Plait, Pnina Ohanna, Ph.D.
University of California.
Berkeley,
1994.
185 pp.
Chair: Elizabeth Deakin. Order Number DA%29460
The central question addressed in this dissertation is the role of transportation and communications services and their interplay in the European Economic Community (EEC). The analysis assesses how transportation and communications services are used and produced in European industrial sectors. The relationships between the uses of different modes of transportation and communications services are analyzed at the level of the national economies and industrial branches of Western European countries. Patterns of comparative advantage in transportation and communication within the EEC are investigated. These issues are analyzed empirically, using adaptations of input-output data and methodologies, as well as formal statistical tools. It is found that the transportation and communications sectors differ in the degree of homogeneity of their production across EEC countries, reflecting differences in the degree of integration. Belgium seems to have the strongest comparative advantage both within the EEC and toward nonEEC “Third Countries” for all forms of transportation. The EEC as a whole seems to have strong comparative advantage relative to the rest of the world in maritime and air transport, and weaker advantage in all other forms of transport and communications. One of the main conclusions of the dissertation that transportation and communications use by industry in Europe exhibits strong complementarity and not substitution. Intensity of use by different industrial branches is also assessed and analyzed.
TRAFFIC
ANALYSIS
Accounting for non-random arrivals in the estimate of delay at signalized intersections. Daniel, Janice Rhoda, Ph.D. Texas A&M University, 1995. 134
pp. Chair: Daniel B. Fambro. Order Number DA9534325
The primary objective of this research was to determine the effect of non-random or platoon arrivals on the estimate of delay at signalized intersections. The parameter used to describe the arrival pattern is a variable k that is used in the steady-state delay model to describe stochastic delay. The 1985 Highway Capacity Manual (HCM) delay model uses a fixed value of 0.5 which is based on queuing theory. It describes a queuing model with random arrivals and a fixed service time. Along an arterial where the upstream intersection meters the flow of vehicles to the downstream intersection, the arrivals are no longer random and the k value is, in general, much smaller than that at an isolated intersection. This research provides an estimate of the k variable for arterial conditions using the time dependent formulation found in the HCM delay model to estimate incremental delay. An analytical
Optimisation of train schedules to minim& transit time and maximise reliability. Higgins, Andrew, Ph.D. Queensland University of Technology. 1996. 260 pp. (Available from Inter-library loans, Gardens
Point Campus, Queensland University of Technology, P.O. Box 2434. Brisbane 400 1, Australia). This research deals with the scheduling of trains on single track corridors to minimize train trip times and maximize reliability of train arrival times. A method to quantify the amount of risk of delay associated with each train, each track segment. and the schedule as a whole is advanced and used as the reliability component of the constrained optimization model. The risk-of-delay mode1 can also be applied to the ranking of investment projects designed to improve timetable reliability. Comparisons can be made between track, terminal and rolling stock projects in terms of their likely impact on timetable reliability. A number of solution techniques for the scheduling problem are described. New lower bounds for the branch and bound technique are presented which allow solutions for reasonable size train scheduling problems to be efficiently determined. Three solution heuristic techniques are applied to the train scheduling problem: a local search heuristic with an improved neighborhood structure, genetic algorithms with an efficient string representation, and tabu search. The heuristic and branch and bound techniques are compared in terms of number of calculations and solution quality. The branch and bound technique with the best lower bound out-performed genetic algorithms and tabu search for all except the largest problems. The model and solution techniques are applied to the problem of modeling the number and location of sidings on a single track corridor. with respect to a given schedule. A decomposition procedure is used
71
to partition the model into easily solvable submodels. The procedure converged quickly, and numerical results indicate savings in terms of train trip times and schedule reliability when track sid-
ings are at improved positions. The train scheduling model and solution techniques are then applied to an actual track corridor. The optimal train schedule is found to have considerably less delay due to conflicts than the schedule as resolved by rail operations planners.
Railway-caused road traffic in catchment areas of stations. Brocke, Delia, Dip].-Ing. Universitdt Karlsruhe (Germany). 1995. 177 pp. (in German).
This dissertation deals with the travel behavior of passengers who are accessing or leaving a rail station. It examines the sequence of all modes of transport taken to reach the station, as well as the respective access times. Then, a special analysis of the routes used by railway passengers to get to the station on the road is conducted. Interviews at the central stations of Karlsruhe and Stuttgart were used to collect empirical data. On the basis of origins and destinations. the station’s catchment areas are derived from specially-developed delimitation criteria. These catchment areas are extremely large as illustrated by the long access times. The number of road vehicles which serve interviewees as feeders to the station is extrapolated to the number of vehicles used for access and departure by all tail passengers. This railway-caused road traffic can be set into a ratio to the total traffic on the roads in the catchment areas by which the so-called “road using rates” are obtained. They are differentiated between “section-related” and “area-related” roads using rates either for single road sections or for specified reference areas. The determined values of the road using rates are found to be exceedingly low. It can be concluded that the volume of the railway-caused road traffic is minimal in comparison to the total road traffic and that consequently the railway passengers’ vehicles do not produce substantial additional traffic on the roads.
TELECOMMUNICATIONS/ TRANSPORTATION RELATIONSHIPS Adoption of telecommuting: Modeling the employer’s and the employee’s decision processes. Bernardino, Adriana Teixeira, Ph.D. Massachusetts Institute of Technolog_v. 1995. Supervisor: Moshe Ben-Akiva.
This research develops a comprehensive model of the telecommuting adoption process, incorporating both the employer’s and the employee’s perspectives. A probabilistic modeling approach is taken. The employer’s decision to offer a telecommuting program to his/her employees is modeled as a function of his/her motivations and constraints. and of the perceived impacts of telecommuting on the organization’s productivity and
72
Recent doctoral dissertations
costs. The employee’s decision to adopt an available telecommuting program is modeled as a function of his/her motivations and constraints, as well as of the impacts of the available program on lifestyle quality, work-related costs and income. The results indicate that telecommuting has significant potential to increase productivity and improve lifestyle quality, if the right program is designed for the right employee. The potential of telecommuting to reduce organizational and employee work-related costs is perceived to be limited. A generally negative perception about the potential impacts of telework-center based telecommuting programs on productivity and lifestyle quality is identified. Telecommuting has a significant potential to reduce work trips, and that this potential can be further enhanced as experience with such arrangements increases. These results indicate that a positive experience with telecommuting can increasing the level of adoption. (Copies available exclusively from MIT Libraries, RM. 14-0551, Cambridge, MA 021394307. Ph. 617-253-5668; Fax 617-253-1690.)
Trattsportation and telecommunications: Potential interactions between physical and immaterial [virtual] travel. Divieti, Laura, Ph.D. University of Trieste (Italy), 1995. 146 pp. Chairman: Claudio Podesta.
Information-based alternatives to travel have led to the concept of the transportation system and the telecommunication network as an integrated teletrans (telecommunications-transportation) network. With innovative telecommunications technologies, it is now possible to move instantly from one place to another, accessing information in real-time, virtually eliminating travel distance and time. In the long-term, we expect that various activities (e.g., work, shopping, leisure and so on) will be differentially affected by the electronicallybased ‘no-travel’ option. Availability of telecommunications does not necessarily imply that users will always choose the no-travel option, but it will clearly change the choice set and decision-making process. A preliminary modeling framework to evaluate the teletrans concept is presented by means of a probabilistic approach (random utility model). An empirical survey, carried out to validate the proposed model, highlighted the influence of personal attitudes on the perception of various options. Telematic applications will be evaluated by potential users from an individual viewpoint (e.g., physical and social isolation, conflicts between private and working life) and an organizational viewpoint (e.g., management control, issues related to information access, implementation costs, etc.). The communication contexts (e.g. purpose, urgency, value and complexity); the ease of use and reliability of telematic equipment; and increasing congestion, time lost to travel, and stress will also play a role.
Transportation/communications relationships in the European community. Plait, Pnina Ohanna, Ph.D.
University of California.
Berkeley,
1994.
185 pp.
Chair: Elizabeth Deakin. Order Number DA%29460
The central question addressed in this dissertation is the role of transportation and communications services and their interplay in the European Economic Community (EEC). The analysis assesses how transportation and communications services are used and produced in European industrial sectors. The relationships between the uses of different modes of transportation and communications services are analyzed at the level of the national economies and industrial branches of Western European countries. Patterns of comparative advantage in transportation and communication within the EEC are investigated. These issues are analyzed empirically, using adaptations of input-output data and methodologies, as well as formal statistical tools. It is found that the transportation and communications sectors differ in the degree of homogeneity of their production across EEC countries, reflecting differences in the degree of integration. Belgium seems to have the strongest comparative advantage both within the EEC and toward nonEEC “Third Countries” for all forms of transportation. The EEC as a whole seems to have strong comparative advantage relative to the rest of the world in maritime and air transport, and weaker advantage in all other forms of transport and communications. One of the main conclusions of the dissertation that transportation and communications use by industry in Europe exhibits strong complementarity and not substitution. Intensity of use by different industrial branches is also assessed and analyzed.
TRAFFIC
ANALYSIS
Accounting for non-random arrivals in the estimate of delay at signalized intersections. Daniel, Janice Rhoda, Ph.D. Texas A&M University, 1995. 134
pp. Chair: Daniel B. Fambro. Order Number DA9534325
The primary objective of this research was to determine the effect of non-random or platoon arrivals on the estimate of delay at signalized intersections. The parameter used to describe the arrival pattern is a variable k that is used in the steady-state delay model to describe stochastic delay. The 1985 Highway Capacity Manual (HCM) delay model uses a fixed value of 0.5 which is based on queuing theory. It describes a queuing model with random arrivals and a fixed service time. Along an arterial where the upstream intersection meters the flow of vehicles to the downstream intersection, the arrivals are no longer random and the k value is, in general, much smaller than that at an isolated intersection. This research provides an estimate of the k variable for arterial conditions using the time dependent formulation found in the HCM delay model to estimate incremental delay. An analytical