The British port transport industry part 2. Employment, working practices and productivity

The abolition of the national Dock Labour Scheme presented with the oppurtunity radically to transform their cargo handling operations. Port employers have seized this oppurtunity and introduced radical changes to workforce compositions, their skills, work practices, and employee relations. The main factor behind these changes has been the desire of operation to minimize labour costs and maximize labour utilization in order to amintain traffic volume and competitive advantage. The short-term effect has been to improve productivity and profitablity(at least for the major port authorities), but it has also produced iinstablity in employee relations ans may in the long term prove counter productive>     

A step towards risk-based decision support for ships – Evaluation of limit states using parallel system analysis

Onboard decision support systems (DSS) are used to increase the operational safety of ships. Ideally, DSS can estimate future ship responses within a time scale of the order of 1–3 h taking into account speed and course changes, assuming stationary sea states. In principle, the calculations depend on a large amount of operational and environmental parameters, which will be known only in the statistical sense. The present paper suggests a procedure to incorporate random variables and associated uncertainties in the calculations of the outcrossing rates that are the basis for risk-based DSS. The procedure is based on parallel system analysis, and the paper derives and describes the main ideas. The concept is illustrated by an example, where the limit state of a non-linear ship response is considered. The results from the parallel system analysis are in agreement with corresponding Monte Carlo simulations. However, the computational speed of the parallel system analysis proved slower than expected.     

Constrained Optimal Control of Semi-Active Suspension Systems with Preview

Controllers for semi-active suspensions have to account for constraints on damper range, tire force and suspension travel. Two approaches to incorporate these constraints in the design of controllers to minimize peak values in the chassis acceleration are considered. It is assumed that information on the oncoming road elevations (preview) is available. In the soft constraint approach, the constraints on tire force and suspension travel are included in a quadratic performance index. Two clipped optimal control laws, which deal with preview in a different way, are presented. Simulation results with a 2-DOF vehicle model on some rounded pulses show that these laws do not work satisfactorily with respect to the constraints. Therefore, the control problem is reformulated as a constrained optimization problem with hard constraints on tire force and suspension travel. Simulations with the same model on the same rounded pulses show that the hard constraint approach handles the constraints more properly.     

Preview Estimation and Control for (Semi-) Active Suspensions

An active suspension with preview is tested for rounded pulses and a stochastic road surface, and is compared to a passive suspension. The spectacular performance improvement obtained for a step function as road surface is not achieved but the improvement is still significant. The frequency response of the active suspension is determined for comparison with some suspension systems found in literature

An observer to reconstruct the preview information is presented. No model of the road surface is needed. From simulations, it appears that the observer reconstructs both deterministic and stochastic road surfaces satisfactory. However, the influence of measurement noise is not reduced sufficiently.     

Defining domains for models of travel demand

Travel demand models implicitly assume that people respond to changes in a continuous way. This is in contrast to the physical sciences, where discontinuous response is a common phenomenon and is embodied in such concepts as sub-critical and supercritical states.Recent studies have shown that responses to transport policies differ in degree and kind according to the nature and severity of the stimulus and the types of people affected. Response patterns may be categorised by the extent to which they involve adjustments to spatio-temporal or inter-personal linkages. This paper identifies four response domains, with a further distinction between permissive and forced changes.Most travel demand models are designed to operate within an independent, forced (and to a less extent independent permissive) domain and their forecasts become unreliable when responses lie outside that domain. Conversely, a model designed for a more complex domain is unnecessarily cumbersome where simpler responses apply. This paper describes the types of model which are appropriate for each domain and discusses how the effects of a policy may be assigned to the correct domain(s).     

An Analysis of a Civil Aircraft Main Gear Shimmy Failure

A dynamical model is presented to analyse the stability of motion of the two-wheeled 'Fokker F.28-like' landing gear including tyres. The model is equally applicable to similar landing gears. The influence of the introduction of a specially designed torsional damper on the dynamical behaviour of the landing gear-tyre combination is investigated. Results of the stability calculations are supported by test results.     

Strategic re-thinking in shipping companies

This article proposes a framework for how successful shipping companies can develop strategies for growth and take advantage of business opportunities. It is essential to strengthen strategy implementation to trigger faster, internallygenerated and profitable business growth. Formal planning and control systems, as they traditionally exist in shipping companies, need to be modified to allow for such growth. The forward-thinkers, the truly dynamic companies, will be able to perceive business opportunities before anyone else, mobilize their people, and implement the necessary strategies. In doing so, a balance must be struck between the everyday and visionary focus, between the top-down and bottom-up focus, between the business and corporate portfolio focus. Shipping companies can learn from the example of the progressive business leaders in other fields, capitalizing on their way to succeed and grow, by developing a dual capability to ‘see’ new opportunities and to ‘mobilize’ the relevant organizational resources to implement these. Examples from successful shipping companies are provided.     

The competitiveness of short sea shipping in multimodal logistics supply chains: service attributes

In Europe, ports are confronted with a closer integration in the maritime and shipping industries. The co-operation agreements can take several forms such as alliances and mergers among shipping lines, conferences, involvement of shipping companies in terminal management, and extending interests in inland transport of shipping companies. In this paper we give a brief overview of these different types of agreement and we examine the consequences of this evolution of the market structures in which ports and shipping companies have to operate. More specifically, attention goes to the competitive position of the port in this new environment. It is clear that the role of the port and the port authorities has to be redefined to guarantee that it remains a fully fledged player in this fast evolving integrated market.     

Further developments in the pricing of local public transport

Abstract

This short paper supplements and updates the writer's Recent Developments in the Pricing of Local Public Transport Services, Transport Reviews, 1 (2), pp. 127–150 (1981). That paper described the situation as at 1980 in Britain, with some examples from other countries. This paper updates the position with regard to four main issues:

(a) Impact of the Transport Act 1980 in Britain, which has virtually removed fares control from stage carriage services, and removed all price and quantity control from express services by road.

(b) Further development of zonal pricing, travelcards and off‐bus fare collection on urban systems, and the effects of price reductions (and subsequent increases) in London, West Midlands, and Merseyside.

(c) Problems concerning the legality of financial support for fares policies in British cities.

(d) Following a presentation of work arising from the earlier paper at the meeting of the Transportation Research Board in Washington, D.C. in January 1983, the contrast between British and American policy is reviewed, with the writer's personal view on current policy there.

In addition, evidence on certain other points in the text is updated.