Optimization of bus allocation to depots by minimizing dead kilometers

In metropolitan cities, public transportation service plays a vital role in mobility of people, and it has to introduce new routes more frequently due to the fast development of the city in terms of population growth and city size. Whenever there is introduction of new route or increase in frequency of buses, the non‐revenue kilometers covered by the buses increases as depot and route starting/ending points are at different places. This non‐revenue kilometers or dead kilometers depends on the distance between depot and route starting point/ending point. The dead kilometers not only results in revenue loss but also results in an increase in the operating cost because of the extra kilometers covered by buses. Reduction of dead kilometers is necessary for the economic growth of the public transportation system. Therefore, in this study, the attention is focused on minimizing dead kilometers by optimizing allocation of buses to depots depending upon the shortest distance between depot and route starting/ending points. We consider also depot capacity and time period of operation during allocation of buses to ensure parking safety and proper maintenance of buses. Mathematical model is developed considering the aforementioned parameters, which is a mixed integer program, and applied to Bangalore Metropolitan Transport Corporation (BMTC) routes operating presently in order to obtain optimal bus allocation to depots. Database for dead kilometers of depots in BMTC for all the schedules are generated using the Form‐4 (trip sheet) of each schedule to analyze depot‐wise and division‐wise dead kilometers. This study also suggests alternative locations where depots can be located to reduce dead kilometers. Copyright © 2015 John Wiley & Sons, Ltd.     

Derivation of delays based on improved macroscopic traffic models

Recent improved and rigorous mathematical models describing the formation and dissipation of queues at signalized intersections are employed for deriving delay and effective queue size. Analytical and numerical solutions are presented that are applicable for both isolated and coordinated intersections. Comparisons against results obtained from conventional models reveals significant differences. Further, it is demonstrated that the current practice of calculating delays from input-output analysis results in substantial overestimation of delays. Numerical examples supporting this finding are presented.     

The most likely trip matrix estimated from traffic counts

For a large number of applications conventional methods for estimating an origin destination matrix become too expensive to use. Two models, based on information minimisation and entropy maximisation principles, have been developed by the authors to estimate an O-D matrix from traffic counts. The models assume knowledge of the paths followed by the vehicles over the network. The models then use the traffic counts to estimate the most likely O-D matrix consistent with the link volumes available and any prior information about the trip matrix. Both models can be used to update and improve a previous O-D matrix. An algorithm to find a solution to the model is then described. The models have been tested with artificial data and performed reasonably well. Further research is being carried out to validate the models with real data.     

Commercializing management and financing of roads in developing and transition countries

The road sector reforms undertaken by a growing number of developing and transition countries during the past 10-20 years are described. The problems these countries share with industrialized countries and the additional factors that also affect them--large backlogs of deferred maintenance, an acute shortage of funds and dysfunctional road agencies--are also described. The paper then describes how these countries have restructured road management by separating planning and management of roads from implementation of works, provided road agencies with more autonomy, created more effective oversight, introduced annual performance agreements and turned the road agency into a more commercial organization paying market-based wages. In relation to road financing, road tolls and toll roads are touched on briefly before the new style road funds that have recently been set up in these countries are detailed. The paper then describes how they were established and their basic operating modalities--revenues only from charges related to road use (with one notable exception), no abstraction of revenues from other sectors, proactive management and oversight provided by a board of directors that includes members nominated by road users and the business community.     

Shipwrecks: The past in the present

Abstract

Historic shipwrecks are a recently recognized group of historic resources. These shipwrecks attract sport divers, archeologists, and treasure hunters. States have always claimed the historic shipwrecks embedded in their submerged lands. States manage these resources as part of their historic preservation programs. However, since 1981, state authority has been challenged by the federal court sitting in admiralty. Cases have been decided in Florida, Massachusetts, Maryland, Texas, and Georgia; however, only one Florida case went against the states but the expensive litigation has been a drain on state treasuries.

Bills currently before the U.S. Congress will affirm state title and encourage states to put effort into state programs for historic shipwrecks. This article briefly describes the populations interested in shipwrecks, current case law, state law and state programs, and finally the federal legislative proposal.     

The Decline of the Artisanal Fisheries in Mediterranean Coastal Areas: The Case of Cap de Creus (Cape Creus)

This article examines the sociocultural, economic, and environmental causes of the decline of the artisanal fisheries in the rocky coast of Cape Creus (NW Mediterranean) over the past decades. The changes that have occurred over time have favored trawlers, purse-seiners, shellfish fisheries, and tourism activities, to the detriment of artisanal fisheries. This article shows that the establishment of a marine reserve in 1998 could not reverse the observed decline in the artisanal fisheries. This raises the necessity of implementing a fishery management plan integrated into a coastal management plan, which should accompany the habitat protection. These plans could assist in the maintenance and the sustainable development of the artisanal fishing sector in Cape Creus as well as in other Mediterranean coastal areas where artisanal fisheries are also declining.     

Comparison of inter‐city bi‐modal split models

Using data collected from rail and air passengers on two inter‐city routes in the U.K., seven different model formulations were set up and tested in order to ascertain the most appropriate model format. As a result of the work carried out, it is concluded that a simple Entropy‐type model based on the theoretical work of A. G. Wilson and utilising a linear generalised cost function is the most suitable. Other useful parameters emerging from the work are perceived values of travel time, and a weighting factor for night travel.     

Study on rail corrugation of a metro tangential track with Cologne-egg type fasteners

In Chinese metro lines, rail corrugation on both tangential and tight curved tracks with Cologne-egg type fasteners is very severe. Based on the viewpoint of friction-induced vibration causing rail corrugation, the rail corrugation on a tangential track with Cologne-egg type fasteners is studied in this paper. A vibration model of an elastic multiple-wheelset-track system with Cologne-egg type fasteners is established. Both the complex eigenvalue analysis and the transient dynamic analysis are performed to study the stability and the dynamic performance of the wheelset-track system. The simulation results show that a low rail support stiffness value is responsible for rail corrugation on the tangential track. When the Cologne-egg fasteners characterised by a lower stiffness value are replaced with the DTVI2 fasteners characterised by a higher stiffness value, rail corrugation disappears. However, rail corrugation on tight curved tracks cannot be suppressed using the same replacement. The above conclusions are consistent with the corrugation occurrences in actual metro tracks.     

Stakeholder Collaboration and Organizational Innovation in the Planning of the Deschutes Estuary Feasibility Study

Coastal managers have sought to enhance the collaborative inputs of stakeholder groups into management activities. Nonetheless, established organizational approaches have led to primarily consultative forms of engagement and constrained citizen involvement in formative activities. In Olympia, Washington, managers overseeing the Deschutes Estuary Feasibility Study (DEFS) implemented an innovative cooperative research planning initiative that diverged from conventional consultative processes. Stakeholders, rather than government officials, identified the research priorities for the socioeconomic component of this restoration feasibility study. This design method altered the traditional roles and responsibilities of different organizational actors, and the involvement of citizen groups in these formative activities changed the relationship between governmental and nongovernmental actors. Using conceptual frameworks from organizational sociology, this study develops insights into the behavior of the organizations involved with the DEFS cooperative planning effort, demonstrating how engaging stakeholders in formative research planning activities may foster new types of collaboration among coastal management organizations.