Multiuser virtual safety training system for tower crane dismantlement

Tower crane dismantling is one of the most dangerous activities in the construction industry. Tower crane erection and dismantlement causes 10–12% of the fatalities of all crane accidents. The nature of the task is such that off-the-job training is not practicable, and the knowledge and expertise needed has to be gained on the job. However, virtual trainers such as Microsoft Flight Simulator for airplane pilots and mission rehearsal exercise (MRE) for army personnel have been developed and are known to provide a highly successful means of overcoming the risks involved in such on-the-job learning and clearly have potential in construction situations. This paper describes the newly developed multiuser virtual safety training system (MVSTS) aimed at providing a similar learning environment for those involved in tower crane dismantlement. The proposed training system is developed by modifying an existing game engine. Within the close-to-reality virtual environment, trainees can participate in a virtual dismantling process. During the process, they learn the correct dismantling procedure and working location and to cooperate with other trainees by virtually dismantling the crane. The system allows the trainees to experience the complete procedure in a risk-free environment. A case study is provided to demonstrate how the system works and its practical application. The proposed system was evaluated by interviews with 30 construction experts with different backgrounds, divided into three groups according to their experience and trained by the traditional and virtual methods, respectively. The results indicate that the trainees of the proposed system generally learned better than those using the traditional method. The ratings also indicate that the system generally has great potential as a training platform.

Integrating real time positioning systems to improve blind lifting and loading crane operations

Mobile/tower cranes are the most essential forms of construction plant in use in the construction industry but are also the subject of several safety issues. Of these, blind lifting has been found to be one of the most hazardous of crane operations. To improve the situation, a real-time monitoring system that integrates the use of a Global Positioning System (GPS) and Radio Frequency Identification (RFID) is developed. This system aims to identify unauthorized work or entrance of personnel within a pre-defined risk zone by obtaining positioning data of both site workers and the crane. The system alerts to the presence of unauthorized workers within a risk zone——currently defined as 3m from the crane. When this happens, the system suspends the power of the crane and a warning signal is generated to the safety management team. In this way the system assists the safety management team to manage the safety of hundreds of workers simultaneously. An onsite trial with debriefing interviews is presented to illustrate and validate the system in use.

A quay crane scheduling methodology for multimodal container terminals

This thesis develops an operational decision support tool for container terminal managements. The tool generates efficient schedules for shore cranes handling containers carried by mega container vessels.

Diurnal time budget of the Black-necked Crane during the breeding season

From 26 March to 2 August 2003, both the time budget and the diurnal rhythm of behavior of breeding Black-necked Cranes (Grus nigricollis) were studied at Ruoergai Wetlands National Natural Reserve, Sichuan Province, China. The breeding season was divided

Nest site selection by Black-necked Crane Grus nigricollis in the Ruoergai Wetland, China

From 5 May 2003 to early June 2005, nest site selection of Black-necked Cranes Grits nigricollis was studied at the Ruoergai Wetland Nature Reserve (RWNR), an important breeding area for the species in China. Results showed that the crane nests only in we

[Book review] Reviews. [1] Nicholas Crane, Mercator: The Man Who Mapped the Planet, London: Weidenfield and Nicolson, 2002. [2] Stephen Inwood: The Man Who Knew Too Much: The Strange and Inventive Life of Robert Hooke (1635-1703), London: Macmillan, 2002

Book reviews of: [1] Nicholas Crane, Mercator: The Man Who Mapped the Planet, London: Weidenfield and Nicolson, 2002, £20, ISBN: 0297646656. [2] Stephen Inwood: The Man Who Knew Too Much: The Strange and Inventive Life of Robert Hooke (1635-1703), London: Macmillan, 2002, £18.99, ISBN: 0333782860.

Adaptive tackling of the swinging problem for a 2 DOF crane – payload system

The control of a crane carrying its payload by an elastic string corresponds to a task in which precise, indirect control of a subsystem dynamically coupled to a directly controllable subsystem is needed. This task is interesting since the coupled degree of freedom has little damping and it is apt to keep swinging accordingly. The traditional approaches apply the input shaping technology to assist the human operator responsible for the manipulation task. In the present paper a novel adaptive approach applying fixed point transformations based iterations having local basin of attraction is proposed to simultaneously tackle the problems originating from the imprecise dynamic model available for the system to be controlled and the swinging problem, too. The most important phenomenological properties of this approach are also discussed. The control considers the 4th time-derivative of the trajectory of the payload. The operation of the proposed control is illustrated via simulation results.

Résidence de Charles [Richard] Crane à Woods Hole (Mass.) [Massachusetts] qui sera probablement celle de Wilson [résidence d'été] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 58888

Le crane des criminels

UANL

Application of constrained predictive control on a 3D crane system

This paper describes the SIMULINK implementation of a constrained predictive control algorithm based on quadratic programming and linear state space models, and its application to a laboratory-scale 3D crane system. The algorithm is compatible with Real Time. Windows Target and, in the case of the crane system, it can be executed with a sampling period of 0.01 s and a prediction horizon of up to 300 samples, using a linear state space model with 3 inputs, 5 outputs and 13 states.

The re-identification of great bustard (Otis tarda) from Fishbourne Roman Palace, Chichester, West Sussex, as common crane (Grus grus)

This paper details the results of recent reanalysis of the animal remains from the 1960s excavations at Fishbourne Roman Palace, West Sussex. It argues that specimens originally identified as belonging to the great bustard are, in fact, misidentified remains of common crane. This discovery has important connotations. First, these findings need to be reported so that the avian archaeological record can be updated to avoid future syntheses of Romano-British faunal remains incorrectly including great bustard. Secondly, interpretations of the zooarchaeological remains at Fishbourne Palace will alter, due to the differing ecological histories of bustards and cranes.

Power demand and energy usage of container crane - comparison between AC and DC drives

The electrical data of two quay cranes, one has a DC drive system and the other has an AC drive system, in actual working conditions at a container terminal are measured and presented in this paper. Peak demand, energy usage, power factor and power quality are examined and compared.