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The purpose of this paper is to evaluate the effect of main parameters and their interactions on the workers' Lifting Index in a steel rolling mill.

NIOSH (National Institute for Occupational Safety and Health) lifting equation has been used to evaluate the risk of lifting tasks with respect to low back injury under varying load (10, 15, 20 kg), frequency (2, 3, 4 lifts/min), and twisting angle (0, 30, 45 degree).

The level of importance of the parameters on lifting index at origin and destination has been determined using analysis of variance (ANOVA).The analysis draws on lifting parameters and uses both main effects and interactions to describe the variation in Lifting Index and to identify the social influence associated with back injury. The interactions between object weight and twisting angle and object weight and lifting frequency turn out to be significant (p<0.05), whereas the interaction between twisting angle and lifting frequency is less significant (p=0.061).

The study includes a specific location (steel rolling mills located in Jammu region of India) only.

The findings suggest that focus should be made on all lifting parameters, rather than sole emphasis on the load to be lifted.

The paper supports the view that load, twisting angle and lifting frequency greatly influence the physical stressfulness of the task. It is suggested that the workplace should be designed for negligible twisting and moderate lifting frequency, so as to have minimum Lifting Index.

This paper provides an overview of a recently developed system for selecting and locating mobile cranes on construction sites. The proposed system provides direct help on two fronts: cost and time savings, and improved safety arrangements. The system has a number of interesting features: a relational database designed to store the cranes' geometry‐related variables and to present them using powerful graphics; a selection module supported by an algorithm designed to satisfy geometrical requirements and necessary clearances, accounting for site constraints and lift configurations; and 3D animation to facilitate the planning of crane operations. The system provides a near‐optimum selection of crane lift configurations, considering available cranes. This paper focuses mainly on case examples to demonstrate and to illustrate the use and capabilities of the developed system. Two actual cases, featuring different site constraints and lift configurations, are presented. In these cases, cranes were selected and their operations planned using the developed system. The findings of the two cases are discussed and the benefits of the proposed methodology are highlighted.

THE ability of an aircraft to take‐off and land vertically can be achieved by a number of design techniques. Those currently favoured vary from the use of a large rotor (as in the helicopter) through propeller‐driven tilting wings and large ducted fans to small jet lift engines. Three major design parameters which affect the final choice of technique arc take‐off and hovering efficiency, cruising flight efficiency (involving, as it may do in the case of helicopters, limitations on forward speed) and the velocity of the lifting jet which will influence noise level and ground erosion problems. The use of the tilting wing, rotor, and to a lesser degree ducted fans places a comparatively severe restriction on the performance of aircraft required for military operations at high speeds and high altitudes, and consequently the turbojet lifting engine appears to offer the best solution to the vertical take‐off and landing problem for this type of application.

Offers guidance on how to achieve proper maintenance of building lifts. Details equipment audit and the maintenance contract. Discusses lift operations, performance measurement, user requirements and insurance and legal requirements. Finally looks at remote and third party monitoring.

The subject of lifts covers a wide spectrum from the highly technical to the subjective and emotional response of individuals. This article focuses on a design brief for groups of passenger lifts suitable for low‐rise buildings where intensive traffic is encountered. What does the building planner in collaboration with his architect need to know?

Introduction Surveys of lift installations are required for many reasons. In some cases, the frequency of breakdowns and stoppages becomes so great that the occupants of the building require the cause to be established by an independent surveyor, who is unconnected with the lift company responsible for maintenance, or with the landlord. There is also the situation where, while there have been numerous breakdowns, the lift service is maintained overall, but with a consequently high maintenance premium, involving a steady stream of bills for repairs and replacement parts. In such cases, it is important to establish that the contractor's claims are justified and that he is not increasing his profits by preying on laymen's limited knowledge.

This paper presents a newly developed algorithm for selecting and locating mobile cranes on construction sites. The algorithm is incorporated into a computer system that integrates a selection module and three databases, dedicated respectively, for cranes, rigging equipment, and projects’ information. This paper focuses primarily on the selection module and its algorithm to support an efficient search for most suitable crane configurations and their associated lift settings. Data pertinent to crane lift configurations and settings are retrieved from the databases and processed to determine the near optimum selection of a crane configuration. The developed selection module features powerful graphics capabilities and a practical user‐friendly interface, designed to facilitate the considerations of user imposed lift and site constraints. The selection algorithm has been implemented within the crane selection module using MS‐Visual Basic programming language. A case example is presented in order to demonstrate the use of the developed selection module and to illustrate its essential features.

Twenty‐five years ago lift installations were almost invariably serviced by the manufacturing company that installed them and although, as is always the case, comprised a mixture of electro‐mechanical as well as electrical components, the electrical systems were relatively straightforward and within the scope of the servicing engineer.

With the falling prices and increasing sophistication of small computer systems the use of computers in the management of large numbers of lifts has become a practical reality. This article deals with possible changes within existing lift management situations. The planning of new installations will be covered in a future article bringing us another step closer to the intelligent building. The operation of lifts within one or more buildings can be thought of as a hierarchy of functions. At the bottom of the hierarchy, the most basic function is to move a single lift from floor to floor responding to calls registered by passengers. At the next level, that of Group Control, passenger calls on different landing levels are assigned amongst the individual lifts in a group of lifts according to pre‐programmed rules (known as an Algorithm). Lift management is the long term process by which the operation of all the lifts in several groups is optimised and then maintained at a peak of performance. Lift management is thus the top level of the hierarchy and allows the operation of the lifts to be continually ‘tailored’ to the building in which they are located. Without lift management the occupants of the building must ‘tailor’ their requirements to the service provided by the lifts.

Prefabricated building has been widely applied in the construction industry all over the world, which can significantly reduce labor consumption and improve construction efficiency compared with conventional approaches. During the construction of prefabricated buildings, the overall efficiency largely depends on the lifting sequence and path of each prefabricated component. To improve the efficiency and safety of the lifting process, this study proposes a framework for automatically optimizing the lifting path of prefabricated building components using building information modeling (BIM), improved 3D-A* and a physic-informed genetic algorithm (GA).

Firstly, the industry foundation class (IFC) schema for prefabricated buildings is established to enrich the semantic information of BIM. After extracting corresponding component attributes from BIM, the models of typical prefabricated components and their slings are simplified. Further, the slings and elements’ rotations are considered to build a safety bounding box. Secondly, an efficient 3D-A* is proposed for element path planning by integrating both safety factors and variable step size. Finally, an efficient GA is designed to obtain the optimal lifting sequence that satisfies physical constraints.

The proposed optimization framework is validated in a physics engine with a pilot project, which enables better understanding. The results show that the framework can intuitively and automatically generate the optimal lifting path for each type of prefabricated building component. Compared with traditional algorithms, the improved path planning algorithm significantly reduces the number of nodes computed by 91.48%, resulting in a notable decrease in search time by 75.68%.

In this study, a prefabricated component path planning framework based on the improved A* algorithm and GA is proposed for the first time. In addition, this study proposes a safety-bounding box that considers the effects of torsion and slinging of components during lifting. The semantic information of IFC for component lifting is enriched by taking into account lifting data such as binding positions, lifting methods, lifting angles and lifting offsets.