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To propose a new method for controlling the overhead crane systems based on the theory of fuzzy logic with a reduced number of rules than has appeared before in the literature. The proposed fuzzy logic controller (FLC) can be implemented to move the overhead crane along a desired path while ensuring that the payload is swing free at the end of the motion.

In this study, a FLC that includes two rule bases, one for displacement control, the other for swing control, was designed and successfully implemented to move the overhead crane along a desired path while ensuring that the payload is swing free at the end of the motion.

Control simulation results demonstrate that by using the proposed FLC, the overhead traveling crane smoothly moves to the destination in short time with small swing angle and almost no overshoot.

This paper offers practical help to whom are working in controlling the transporting the payloads to the required position as fast and as accurately as possible without collision with other equipments. The proposed FLC can be implemented to move the overhead crane along a desired path while ensuring that the payload is swing free at the end of the motion.

Based on an in-depth case study in the French nuclear industry, this chapter describes what happens when law’s ambiguity meets organizational complexity. While regulation studies suggest that organizations assign managerial values (such as efficiency or flexibility) to their compliance structures, this research focuses on the mixed role of purchasing managers in these processes. Constituting the missing link when explaining the legal regulation of economic activities, these intermediaries defend a financial conception of the firm against a more technical performance oriented solution. This financial conception did not emerge from nowhere, but resulted from the institutionalization of a particular meaning of business regulation within the nuclear industry. However, if values guide organizational behavior, the behavior of the actors can under no circumstances be reduced to these values. Conflicts, misunderstandings, and mistakes are a constitutive part of these process, too.

THIS country is suffering from a serious shortage of skilled workers. This fact was brought into sharp focus when John Brown, the famous shipbuilders, announced two weeks ago that it had been necessary for them to decline a £5 million order because of a lack of labour in the steel and allied trades. The firm and the size of the potential order ensured national attention, but it cannot be accepted as an isolated instance. When the Ministry of Labour tells us that although 3,124 mostly skilled men entered shipbuilding and marine engineering during the last five weeks for which figures are available, but that there remained 2,860 unfilled jobs, or that 3,264 taken into metal manufacturing left 4,637 vacancies, there is need for concern and investigation.

This paper presents a generic simulation model to determine the equipment mix (quay, yard and intra-terminal transfer) for a Container Terminal Logistics Operations System (CTLOS). The simulation model for the CTLOS, a typical type of discrete event dynamic system (DEDS), consists of three sub-models: ship queue, loading-unloading operations and yard-gate operations. The simulation model is empirically applied to phase 1 of the Yangshan Deep Water Port in Shanghai. This study considers different scenarios in terms of container throughput levels, equipment utilization rates, and operational bottlenecks, and presents a sensitivity analysis to evaluate and choose reasonable equipment ratio ranges under different operational conditions.

IN view of the ever‐increasing application of time and motion study techniques in this country it is difficult to understand why so few manufacturers of time and labour‐saving equipment advertise the very items required by work study engineers.

The main objective of this paper is to analyse the roles of the artists’ collective in the creation of socially shared knowledge, concerning Gdansk Shipyard's heritage protection during the urban regeneration process over last ten years, since 2002.

The empirical section of the paper is based on a single case study concerning the artists collective’ ability to build a complex network of social relations, to research cultural heritage of the Gdansk Shipyard, to translate this knowledge into symbolic languages through art-based work and to transmit knowledge to the wider public with an aim to engage in an open dialogic public communication.

The case study draws on insights from participant observation carried out on the premises of the Gdansk Shipyard between years 2000 and 2008 and interviews with individual artists from the collective, conducted between years 2004 and 2006. Data was also drawn from archival research. The exposure in public media was also examined over last ten years, including Internet websites as well as newspapers and magazines’ content.

The case study research indicates that methods and techniques applied by the artists’ collective in researching the shipyard's historical heritage and communicating their findings to the wider public have been more effective than the official planning methods of expert-led post-industrial urban regeneration. Over the last ten years, the artists have succeeded to transform the negative perceptions about the values of the shipyard's cultural heritage and engaged local citizens in the preservation of the historical identities of the place. In 2012, the Mayor of Gdansk has invited representatives of the artists’ collective to the newly established Young City Stakeholders’ Board in order to utilize their knowledge of the shipyard's cultural heritage and their capacity to mediate between various groups involved in urban regeneration planning process as well as to communicate with the wider public.

Despite persistent views in literature that equate public engagement in the planning process of urban regeneration with a kind of “modern utopia”, we argue that participatory process is not only possible in practice but also can be highly effective and democratically ethical.

The purpose of this paper is to compare efficiency scores from the benchmarking exercise with those of previous studies and to discuss the reasons behind diverging results.

This paper uses data envelopment analysis (DEA) on primary data of large container terminals.

The results differ strongly from those available in the literature. Causes for these differences are: public (secondary) data are not always accurate; different terminal types are compared; terminals of different scale are compared; and terminals are mixed with ports.

DEA may be appropriate for container terminal benchmarking, but only if better quality and additional input and output data can be obtained. In its application, the analysis should be controlled for terminal types.

Summary of the state of play in the use of DEA methodologies for comparing the efficiency of container terminals at ports.

Crane plays a very important role in national economy with greatly reduced labor intensity, improved production efficiency and promoted social development as an indispensable auxiliary tool and process equipment. Therefore, its energy consumption becomes an unavoidable topic and in fact, energy consumption of crane is very huge. It has been proved to be the most cost-effective way for reducing energy consumption to establish and implement new energy efficiency standard. Thus, it is necessary to analyze and evaluate the energy efficiency for overhead crane so as to propose a new energy efficiency standard. The paper aims to discuss these issues.

In this paper, four kinds of energy consumption sources of overhead crane is considered, based on which, an energy efficiency grading model for overhead crane based on BP neural network is proposed. Second, DS evidential theory is analyzed and based on it, an energy efficiency evaluation model based on BP neural network and DS evidential theory is proposed. The evaluation procedure is discussed in detail. Then, a case is demonstrated how the evaluation is carried out.

If overhead cranes with different energy consumptions need to be graded according to energy efficiency, the criterions to establish the energy efficiency labels for overhead cranes is proposed in this paper.

The research results can provide energy efficiency standard proposal of overhead crane for relative departments to monitor the design, manufacturing and use of overhead crane.

An energy efficiency grading model for overhead crane based on BP neural network is proposed. An energy efficiency evaluation model based on BP neural network and DS evidential theory is proposed.

From practical perspectives and to improve the working efficiency, trolley transportation and payload hoisting/lowering should be simultaneously controlled. Moreover, in practical crane applications, the transportation time is an important criterion for improving transportation efficiency. Based on these requirements, this paper aims to solve positioning and antiswing control problems and shorten the transportation time for underactuated varying-rope-length overhead cranes.

By choosing trolley acceleration and varying-rope-length acceleration as system inputs, the crane system dynamic model is converted into an equivalent model without linearizing/approximating. Then, based on the converted model and system state constraints, a time-optimal problem is formulated. Further, the original problem is converted into an optimization problem with algebraic constraints which can be conveniently solved. Finally, by solving the optimization problem, the optimal trajectories of system states, including displacements, velocities and accelerations, are obtained.

This paper first provides a nonlinear time-optimal trajectory planner for varying-rope-length overhead cranes, which achieves accurate and fast trolley positioning and eliminates payload residual swings. Meanwhile, all system states satisfy the given constraints during the entire process. Hardware experimental results show that the proposed time-optimal planner is effective and has better performance compared with existing methods.

This paper proposes a time-optimal trajectory planner for overhead crane systems with hoisting/lowering motion. The proposed planner achieves fast trolley positioning and eliminates payload residual swing with all the system states being constrained within given scopes. The planner is presented based on the original nonlinear system dynamics without linearization/approximation.

WE MAKE NO apologies for taking Thomas Paine's classic title for our leader this month. Written all but 200 years ago, it was brought vividly to mind when we read letters in a contemporary journal. From two well‐qualified men in their early fifties, they regretted they could obtain no replies to many applications for employment. They were, all too evidently, considered “too old at 50'.