A break-even model for evaluating the cost of container ships waiting times and berth unproductive times in automated quayside operations

The planning, design and development of a container terminal with optimum size and capacity and with a minimum capital cost is fundamentally dependent upon the loading and discharging operations at the quayside. The quayside function of container terminals is dependent basically on the number of berths available to service the incoming container ships. The objective of the container terminals dealing and admitting the ongoing ship calls is to provide immediate berth and loading and discharging services to the container ships with a minimum costly waiting time and a maximum efficiency. Previously terminal planners used to build extra berths to provide service. During the last two decades the terminal operators have adopted automation technologies in loading and discharging operation of the container ships as an alternative to designing extra berths. Ship owners naturally expect least waiting times for their container ships. On the other hand, it is also natural for port operators in a container terminal with costly facilities to see a high berth occupancy and productivity at the quayside. This study uses queuing theory to find a break-even point as a way of evaluating the cost of container ship waiting times and the cost of berth unproductive service times for container terminals aiming to automate their quayside operation. The analysis illustrates that automation devices installed on conventional Quayside Cranes (QSCs) significantly reduce the turnaround time of the container ships calling at the ports. It argues, however, that there should be a balance between the cost of berth unproductive service times and the cost of vessel waiting times. The study introduces a break-even point to be considered as a benchmark for calculating such a balance. The analysis in this study can be used as a decision tool for the operators of container terminals in the medium to small ports to appraise the feasibility of an investment in automation or expansion of the quayside facilities.     

Geography and Coastal Management

This article presents an overview of the relationship between geography and coastal management. It explores the nature of geography as well as the geographical underpinnings of key notions within coastal management, in particular, “coast,” “conflict,” and “integration.” The article considers the integrated coastal management process and tracks the influence of geography on the development of the discipline's theory and practice, as well as its academic infrastructure. The article concludes that although geography both underpins and offers useful insights into coastal management, a challenge remains to explore in greater depth the benefits of applied geographical approaches to the management of coasts.     

The crisis for transportation planning modelling

The paper considers the performance of land‐use transportation study techniques over the past ten years. Although primarily viewed from a U.K. perspective the paper reviews matters of principle which are of international relevance. The changing context and tasks for modelling are reviewed and the current role and applications of such models considered. The capability of established models to meet these changing requirements is examined. Attention is drawn to model specification and the ability of models both to represent new policies and to predict traveller responses to them. Also relevant is the ‘behavioural’ theme and the way in which survey technique conditions the data obtained.

Particular emphasis is placed on the accuracy of modelling, both in the representation of base year travel patterns and in the forecast mode. The inherent uncertainty concerning input data is discussed and the frequent failures to establish model validity are noted.

Three crises for U.K. transportation planning practice are identified: the ageing of data bases, the accuracy and validity of models and the current changes to the institutional context of transport planning in the U.K. Some potential remedies for the first two difficulties are proposed. It is concluded that only the last ‘crisis’ represents a real threat to the application of rational methods in transportation planning.     

International Learning Pathways for Coastal Professionals: A Japan–UK Example

This article reports on the Learning Exchange Programme (LEP) model of capacity building for Integrated Coastal Management (ICM) professionals. The LEP model of capacity building involves international group-based exchange visits during which a structured program of experiential learning events is undertaken to meet specific capacity gaps. An application of the LEP model in Japan and the United Kingdom is presented and evaluated, which shows that while refinements could be identified, a group-based, tailored exchange model focused on filling specific capacity gaps is an effective model of capacity building for ICM.     

Effects of road network on vegetation pattern in Xishuangbanna, Yunnan Province, Southwest China

The paper presents the results of a case study carried out in Xishuangbanna, Southwest China, to examine the relationship between vegetation dynamics and road network extension. We find that lower level roads had more effects on vegetation patches. Minor roads, including Class IV and Class V roads, contributed most to regional landscape fragmentation while high level roads had larger effect on vegetation dynamics in road effect zone. Further, road classes have close relationships with village distribution, topography fluctuation and landscape fragmentation. Topography, however had no direct relationship with vegetation pattern.     

Can bus really be the new tram?

BRT appears to be less expensive to build and operate than tram systems but can it really approach the performance level of a tram system and what is the environmental performance of comparable systems?     

Preliminary results from an integrated transportation and land use models package

This paper describes the results, to date, of an effort to integrate a land use model with a transportation network model for the purpose of analyzing the interrelationships of transportation facility development and land development. In the system which has been developed each model provides input to, and receives feedbacks from, each other model. To the author's knowledge, the effort described here represents the first successful attempt to develop and test an integrated model package involving these reciprocal relationships. The results obtained from preliminary runs of this package should be of considerable interest to both transportation planners and land use planners. With this integrated system it has been possible to observe the interrelationships, and in particular the feedbacks, between land use and levels of traffic on the networks. Preliminary results indicate that congested networks produce tendencies toward metropolitan centralization. Attempts to relieve congestion seem to produce metropolitan decentralization and increased travel which lead, in turn, to metropolitan sprawl and increased spread of congestion.     

Incorporating insights from signal optimization into reservation-based intersection controls

Reservation-based intersection control for autonomous vehicles has the potential to make greater use of intersection capacity. Indeed, previous studies on the first-come-first-served (FCFS) policy (which prioritizes vehicles by order of their reservation request) have shown improvements over optimized signals. However, in certain situations, such as asymmetric intersections, FCFS easily performs worse than signals. To address this issue, we propose two new reservation policies, WEIGHTED and PHASED. WEIGHTED weights vehicle delay by signal timings, and PHASED simulates a signal but allows red phase turning movements that will not cause a collision. We test these policies on a city network and an arterial bottleneck intersection subnetwork and show that PHASED performs better than WEIGHTED in some scenarios, and vice versa. Furthermore, we show that using a combination of PHASED and WEIGHTED can perform better than using either one alone for the entire network. Results show that these policies provide effective and easily implemented alternatives to FCFS for reservations.