Valuing Recreation and Amenities at San Diego County Beaches

Abstract

Policymakers and analysts concerned with coastal issues often need economic value information to evaluate policies that affect beach recreation. This paper presents economic values associated with beach recreation in San Diego County generated from a recreation demand model that explains a beach user's choice of which beach to visit. These include estimates of the economic values of a beach day, beach closures, and beach amenities.     

Turn and zigzag maneuvers of a surface combatant using a URANS approach with dynamic overset grids

Unsteady Reynolds averaged Navier–Stokes (URANS) computations of standard maneuvers are performed for a surface combatant at model and full scale. The computations are performed using CFDShip-Iowa v4, a free surface solver designed for 6DOF motions in free and semi-captive problems. Overset grids and a hierarchy of bodies allow the deflection of the rudders while the ship undergoes 6DOF motions. Two types of maneuvers are simulated: steady turn and zigzag. Simulations of steady turn at 35° rudder deflection and zigzag 20/20 maneuvers for Fr = 0.25 and 0.41 using constant RPM propulsion are benchmarked against experimental time histories of yaw, yaw rate and roll, and trajectories, and also compared against available integral variables. Differences between CFD and experiments are mostly within 10 % for both maneuvers, highly satisfactory given the degree of complexity of these computations. Simulations are performed also with waves, and with propulsion at either constant RPM or torque. 20/20 zigzag maneuvers are simulated at model and full scale for Fr = 0.41. The full scale case produces a thinner boundary layer profile compared to the model scale with different reaction times and handling needed for maneuvering. Results indicate that URANS computations of maneuvers are feasible, though issues regarding adequate modeling of propellers remain to be solved.     

Optimization of shipyard space allocation and scheduling using a heuristic algorithm

In this article we describe the development of a tool that allows planners to efficiently and effectively plan space within valuable areas of a shipyard. Traditionally, space is considered as resource; however, it is difficult to accurately account for and plan its consumption with the currently available planning software’s. The spatial scheduling tool described in this article can be used by planners to manually or automatically reserve space within the shipyard for construction of large blocks over the entire erection period of the ship. The software is coupled with a heuristic optimization solver inspired by an algorithm used for "3D bin-packing problems." The result is the ability to efficiently generate and compare multiple space allocation alternatives in a reduced time with the ultimate goal of maintaining the critical ship erection schedule. A better solution than manual or semi-automatic allocation of blocks can be obtained through the optimization module.     

An application of interactive management information systems to environmental planning: Coastal zone management

Recent emphasis in comprehensive planning for coastal zone regions has created the need for more effective tools for information processing and analysis to aid policymakers and planners in developing strategies for preservation of coastal zone areas. New agencies with broad powers have been created at both state and federal levels to deal with growth management in large coastal regions. However, coastal zone management (CZM) agencies have not yet been able to deal effectively with development processes. A “holding action”; is being maintained in the face of mounting pressure by developers, while planners struggle to develop (1) a data base with sufficient detail for planning; (2) a fair and rapid process for reviewing environmental impact statements and granting of development permits; and (3) a system for making the development permit application process more routine. The key to success of the CZM process is the development of a management information system (MIS) created explicitly for CZM. The prototypical system designed by the authors combines graphic display capabilities (i.e., map display) with interactive on‐line computing and large storage‐capacity computers. Problems of data structure development are documented, together with problems of assembling a large‐scale, highly detailed data base. Of particular importance is the need for well‐developed objectives and specifications for the use of computer‐based data in resolving disputes on environmental issues. A set of objectives and specifications for a prototypical coastal zone MIS is developed. The system is described in detail, showing how its capabilities directly address policy questions formulated by coastal zone planners.     

Optimizing shipping company operations using business process modelling

In order to identify the elements constituting quality in services, a business process modelling methodology has been applied in the case of a Greek liner shipping company. The company operations have been identified and analysed in order to assess the complete performance of service elements and thereafter identify how to match the service performance against the user requirements. A liner container service within Europe has to compete with the road transport which, in many cases, is an alternative to the sea transportation and not complementary to it. Thus, not only the ship has to be envisaged when aiming to improve quality in services but also the whole chain, namely port authorities, land transportation enterprises, subcontractors, agents, charterers and others. A set of potential improvements within this framework are thus suggested and time and cost (examined in a specific voyage scenario) are measured before and after the implementation of these measures. Very large time and cost savings are observed after the application of the technology improvements, allowing, in fact, the shipping company to even increase the number of round trips per year in the examined route. This indicates that very large benefits can be drawn by analysing and critically adjusting business processes in modern shipping companies.     

A survey of short sea shipping and its prospects in the USA

Purpose: based on the known in the literature difference between expected and perceived quality, this study examines the factors and the ways that influence the passenger to select a ferry operator.

Methodology/approach: the research attempts to shed some light on the importance of every selection determinant by employing multinomial logistics analysis which identify that the convenience determinant is pivotal when selecting a service.

Findings: the main findings of the study indicate that among six different combinations of factors—models—perceived service quality together with price and convenience (satisfaction determinants) best describe the choice procedure followed by the passenger. The evidence is drawn from a survey performed in the Greek coastal shipping sector.

Originality/value of the paper: to survive in a competitive market, organizations must continuously strive to understand their customers’ wants and needs. Although this is a highly recognized issue in the marketing agenda little or no research has been done on passenger satisfaction and the subsequent selection of a ferry operator.

Practical implications: by using the findings of this work, ferry operators may deeply and timely understand their customers’ purchasing behaviour and adapt their marketing policies especially in a competitive and fast-changing environment.     

Do Road Planners Produce More ‘Honest Numbers’ than Rail Planners? An Analysis of Accuracy in Road‐traffic Forecasts in Cities versus Peripheral Regions

Abstract

Based on a review of available data from a database on large‐scale transport infrastructure projects, this paper investigates the hypothesis that traffic forecasts for road links in Europe are geographically biased with underestimated traffic volumes in metropolitan areas and overestimated traffic volumes in remote regions. The present data do not support this hypothesis. Since previous studies have shown a strong tendency to overestimated forecasts of the number of passengers on new rail projects, it could be speculated that road planners are more skilful and/or honest than rail planners. However, during the period when the investigated projects were planned (up to the late 1980s), there were hardly any strong incentives for road planners to make biased forecasts in order to place their projects in a more flattering light. Future research might uncover whether the change from the ‘predict and provide’ paradigm to ‘predict and prevent’ occurring in some European countries in the 1990s has influenced the accuracy of road traffic forecasts in metropolitan areas.     

Short Sea Shipping’s Green Label at Risk

Abstract

Shifting cargo from land‐based modes to maritime transport has been a prioritized policy in many policy papers to make transport more environmental friendly. Traditional calculations of emissions per transport capacity unit have supported this. However, maritime transport may stand to loose its good environmental reputation in comparison to road transport due to (1) the sluggish processes in maritime environmental policies and the low ambition level of current regulations, (2) the much higher focus on improving the environmental efficiency of the road haulage industry, (3) the much longer economic life of vessels compared to trucks, and (4) focus on faster vessels that increase the average fuel consumption of the sea transport alternative. Through a realistic case study, the energy efficiency and emissions of alternative multimodal transport chains is presented to illustrate these points.