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Aiming at the unbalancing problem of the neutral equilibrium characteristic for balance hoist in the loading process, the purpose of this paper is to establish a dynamic equation for multi-body using the Lagrange method. It is not difficult to find that the deformation of the boom system has a great influence on the stability of the whole system, through the simulation analysis of the multi-rigid-body system model.

Aiming at the unbalancing problem of the neutral equilibrium characteristic for balance hoist in the loading process, the dynamic equation for multi-body is established by Lagrange method. It is not difficult to find that the deformation of the boom system has a great influence on the stability of the whole system, through the simulation analysis of the multi-rigid-body system model.

Result shows that different weights have a great influence on the force deformation and vibration of the boom system of balance hoist. With the increase in lifting weight, the force and deformation of the boom system increase; lead to balance hoist unique with characteristics of indifferent equilibrium, proportional amplification, labor-saving operation will be lost, easy to cause the imbalance of balance hoist. Therefore, the appropriate increase in the basic length of the compression bar, reduction in the basic length of the tension rod and the increase stiffness of the boom system can improve the stability of balance hoist, which provides a reference for the optimization and manufacture of the balance hoist structure.

The simulation model was established by analyzing the working principle and the load condition of the balance hoist, and the simulation and dynamic characteristics of three typical working conditions are analyzed by using ADAMS; result shows that different weights have a great influence on the force deformation and vibration of the boom system of balance hoist. With the increase in lifting weight, the force and deformation of a boom system increase, lead to balance hoist unique with characteristics of indifferent equilibrium, proportional amplification, labor-saving operation will be lost, easy to cause the imbalance of balance hoist.

ENGINEERING'S chief contribution to National Productivity Year has been the joint conference arranged by the Institutions of Mechanical Engineers and Production Engineers. Although the theme was ‘Productivity and the Engineer’, Lord Hailsham, Minister for Science, scanned a wider horizon in his opening address.

I want first to relate the Rules and their preparation to as wide a professional canvas as possible. Secondly, I intend to connect that relationship with the principles upon which the Rules have been based and upon which their structure has been built. And finally I would like to describe briefly how their value has so far been established and related to current library services.

Orders from the USA, orders from the USSR but little from the UK is the current scenario of John Brown Automation. It is a big change from five years ago as Brian Rooks recalls in this profile.

As video-based interventions are continuously utilized as alternatives to physical site visits, directing students' attention to specific learning contents within videos could increase their comprehension and stimulate their interest. Students' knowledge of construction practice can be reinforced, misconceptions and improper inferences can be reduced by calling out significant learning concepts. However, few studies have formalized practice concepts that could be beneficial in preparing students for the workplace. This paper presents an investigation of construction practice concepts, based on site visits that would be beneficial in complimenting classroom teaching to prepare students for the realities of practice.

A mixed methods research approach was employed combining qualitative and quantitative data collection and analysis. An online questionnaire, semi-structured interviews and a focus group were conducted with industry practitioners and instructors to identify the topics and practice concepts significant for supporting classroom teaching with site visits.

The findings suggest that the most relevant topics typically supported with site visits are preconstruction management, excavation and foundation work, construction equipment, construction means and methods, project management, road construction, sustainability, building systems, structures, construction technology, building construction, capstone, site logistics and safety. Practice concepts were identified for each of these topics.

The study will guide researchers in the design of video-based pedagogical tools to be used as an effective complement of or alternative to site visit experiences. The findings will support instructors on how to structure their teaching practices to prepare students for some of the complexities of the workplace.

This study adds value to the existing literature by providing insights into industry perception of practice concepts for complementing classroom teaching.

MISS ANNE SHAW's presence on the platform at the annual general meeting of the Management Consultants Association was a solid assurance that work study still lies within its scope. The initial impression was weakened, however, when the chairman, Mr. D. J. Nicolson, mentioned that the bulk of consultancy work was no longer concerned with work study. Instead, it gave more than half its attention to policymaking and the broad aspects of organising financial, manufacturing and marketing resources.

The purpose of the paper is to explain the successful implementation of organizational applications, and ensuing organizational change, based on a story from a GM manufacturing plant.

The approach involved collecting and analyzing the Hoist Story as part of a multi‐year ethnographic research project designed to identify the key attributes in an ideal plant culture. Through a cooperative process of co‐production, the authors worked in tandem with organizational members on issues related to organizational‐culture change.

The findings emphasize both the Hoist Story's process impact and outcome impact. The Hoist Story was a catalyst for the change process, resulting in a high level of buy‐in across the organization; as such it contrasts with much of the management literature on “planned change.” It also led to the development of several “packaged products” (e.g. a story script, video, collaboration tools) which propelled GM manufacturing culture closer to its ideal – a culture of collaboration. Using employee stories as a means to understand and drive culture change is a largely underdeveloped area of scholarship.

This paper provides value by bridging the gap between theory and praxis. It includes the documentation and cultural analysis of the story, but illustrates how the story evolved into specific organizational‐culture‐change applications. This “soup‐to‐nuts” approach can serve as a model for organizational researchers and change agents interested in spearheading or supporting organizational‐culture change.

IN a departure from usual practice this issue concentrates to a large extent upon a single subject — Mechanical Handling. It coincides with that industry's exhibition at Earls Court from the 9th to 19th of this month, to be opened by the Rt. Hon. Christopher Chataway, M.P., Minister for Industrial Development. In consequence it was necessary to defer some regular features for a time, for which we apologise.

With tower cranes being the site hubs, thoroughly planning and managing their operations can result in better construction performance. As urban spaces become more constricted, overlapping working radii of tower cranes becomes inevitable. While project planners are concerned with safety hazards, research has not comprehensively addressed workload distribution and synchronization of overlapping cranes. Therefore, this study aims at exploring the impact of overlapping cranes, used on high-rise buildings, on operational flexibility which is the balance between schedule duration, crane utilization and safety.

A simulation model was developed and applied on a real project to analyze and compare the impacts of different overlap sizes. Seven scenarios of different overlap sizes, i.e. different number of tasks falling in the overlap space, were executed in the model; their results were plotted and analyzed.

The outcomes result from several compounded factors such as the experience of planners and crane operators, the sequencing of critical versus non-critical activities and the overall effort and care taken when planning operations of overlapping cranes. Increasing overlap size can be beneficial or unfavorable depending on how properly planners allocate overlapping cranes to workload demand, keeping in mind that there are certain trade-offs while achieving operational flexibility.

While project planners are concerned with safety hazards associated with crane overlaps, research has not been comprehensively nor proactively addressing the workload distribution and synchronization of overlapping crane processes. This study contributes to science by addressing the need to harness the flexibility in using overlapping tower cranes while minimizing the resulting interruptions and safety risks. This study sheds light on the potential benefits of allowing cranes to overlap while considering their collision free operations. Operational flexibility is seen as the balance between achieving shorter schedule durations and higher crane utilizations while maintaining collision free motion paths.

The purpose of this paper was to create conditions for the correct decision concerning an exchange of the used rope for a new one. A cognitive goal was to indicate the causes of its wear and determining its mechanism reliability and durability.

The magnetic, organoleptic and strength standard tests of lifting triangle-strand ropes of a mining hoist were carried out. This way the current state of the tested rope was defined.

On the basis of an analysis of the results of the performed tests: magnetic, organoleptic and fatigue tests, it can be said that the magnetic one is accurate enough only to indicate the place of the rope’s biggest weakening, though the degree of weakening is not defined precisely – with significant excess. The accurate rope’s destruction degree is indicated by the strength tests.

The results of described investigations can improve safety of the mining rope mechanisms operation, even for an increased resource.

The elementary wear processes, which are the basic reason for the destruction of the rope, are indicated. Rope destruction is caused mainly by tribological factors: abrasion, corrosion and fatigue wear. Magnetic tests are accurate enough only to indicate the place of the rope’s biggest weakening (qualitative index). Most precisely, the rope’s destruction degree (quantitative index) can be found by the strength tests.