Model Of Working Process Research Articles

A comparative simulation study of work processes in autonomous production cells

AbstractAn approach to human‐centered design and assessment of work processes in flexible manufacturing systems with the help of dynamic task networks is presented. To model and simulate the task networks, the method of timed colored Petri Nets is used. Two task networks are developed. The first task network is a model of work processes in Autonomous Production Cells (APCs). The second task network represents work processes in conventional Computer Numerically Controlled (CNC)‐based manufacturing systems. The material processing technology is associated with 5‐axis milling. The values of attributes of task elements were acquired empirically on a fine‐grained level with reference to a sample milling order. Comparative hypotheses regarding time‐on‐task, supervisory control functions, levels of cognitive control, human error (HE), and labor division were then formulated. To test these hypotheses, several simulation experiments were conducted. The results from inferential statistics show that single‐operator APCs have a 30% higher efficiency in relation to total time‐on‐task. Moreover, the level of cognitive control is significantly shifted toward rule‐ and knowledge‐based behavior. Surprisingly, the simulation of minor HE does not demonstrate a significantly worse performance from APCs. A simulated labor division among central process planner and production operator allows an additional efficiency improvement of approximately 15%. However, the labor division has two important drawbacks: first, a sequential incompleteness of operators' task spectrum occurs; second, the operator has to cope with hierarchical task incompleteness. Finally, a sensitivity analysis was carried out to investigate the effects of varying lot sizes and number of processed orders. © 2002 John Wiley & Sons, Inc.

Mathematical model of GTE working process for calculation of their emission characteristics

Considered are the methods of getting aviation gas-turbine engine emission characteristics. Described is the method of a numerical experiment allowing to take into account the influence of production, technological and performance factors on the emission characteristics of the engine. Presented are the achieved experiment results of the emission characteristics of the engine ПС-90А

Configuration for Adaptation – A Human-centered Approach to Flexible Workflow Enactment

The advantages of today's process management, such as efficiency and quality aspects, are achieved by enforcing detailed models of work processes. However, real world processes can be planned to a limited degree only and sometimes planned parts of the process must be changed, creating a need for additional, unforeseen activities. This paper suggests an approach that configures parts of a detailed process model with different support strategies. The explicit modelling of these support strategies allows them to be changed if demanded by the situation. When enacting such a process model it is then possible to vary the degree to which the model determines the work of individuals. The concept is based on an earlier enactment concept which allowed workers to freely choose methods for their tasks according to the situation. Besides the incorporation of different support strategies, the extended enactment strategy gives workers the opportunity to negotiate about changing a currently too restrictive support strategy, giving scope for deviations from the planned process where additional actions are required.

Enforcement vs. freedom of action an integrated approach to flexible workflow enactment

The advantages of today'sprocess management, such as efficiency and quality aspects, are achievedby enforcing detailed models of work processes. But real world processescan be planned only to a limited degree and sometimes demand changing alreadyplanned parts of the process. So additional, unforeseen activities haveto take place in a process. This contradictory situationwill here be tackled by an approach that combines different forms of enforcementof planned parts of a process. The explicit modelling of these differentsupport strategies allows them to be changed if demanded by the situation.An extended enactment strategy gives workers the opportunity to negotiateabout changing the current support strategy. So there is some thresholdto deviate from the planned process because addtional actions are required.

Early steps in implementing the new community care: the role of social work practice.

This paper presents findings from a research project in which needs-led assessments and care management were examined during the early years of implementation of the 1990 NHS and Community Care Act. The findings are analysed in relation to a model of social work processes, i.e. phases of assessment, intervention and evaluation. A purposive sample of 24 cases was used, spanning elderly, physical disability, learning disability and community mental health teams in two divisions of a 'county' social services department. Practitioners, providers, users and carers were interviewed. The research illustrates the enduring importance of social work values, knowledge and skills in situations of rapid organizational change and policy development.

Work process analysis: a necessary step in the development of decision support systems. An aviation safety case study

This paper demonstrates the importance of work process modeling and supporting data analysis in system development. To illustrate the process of modeling for system development, we describe how traditional task analysis was used in our effort to understand the work processes associated with the Federal Aviation Administration’s (FAA’s) airworthiness and operations surveillance inspection activities. Further, the integration of risk assessment techniques resulted in a validated task analysis providing a review of the as-is state of surveillance activities. It is also shown how the as-is surveillance work processes that resulted from these studies were used as the foundation for a re-engineered ( re-eng) surveillance work process model. We conclude by describing a follow-on activity, the development of a safety critical work process model, which reflects an integration of the as-is and re-engineered work process descriptions, the human factors literature, inspection data analysis, federal aviation regulations and identified areas of safety criticality.

A Concurrent Workflow Management Process for Integrated Product Development

Summary This paper describes a systematic concurrent workflow management (WM) process for integrated product development. WM consists of planning and scheduling teams' activities to support cooperative and concurrent works. This paper first explains process re-engineering, flowcharting and various workflow practices in concurrent engineering (CE) to come up with a general process for WM. The WM process is based on an information infrastructure containing models of product requirements, enterprise organization and resources, including the workflow activity. Finally, technologies supporting WM such as work process modeling, performance analyzing, process re-engineering strategies to redesign the process and activity management-real-time task's monitoring-are introduced.

An assessment of the Sachs method for measuring residual stresses in cold worked fastener holes

Measurements of residual stresses in 6 mm thick aluminium alloy 2024 plates containing 4 per cent cold worked fastener are made using the Sachs method. The measurements are made on discs extracted from the plates. The measured tangential residual stress distribution adjacent to the hole edge are found to be affected by the disc diameter. The measured residual stresses are also in good agreement with averaged through-thickness predictions of residual stresses from an axisymmetric finite element (FE) model of the cold working process. A finite element analysis is also conducted to simulate disc extraction and then the Sachs method. The measured FE residual stresses from the Sachs simulation are found to be in good agreement with the averaged through-thickness predicted residual stresses. The Sachs simulation was not able to reproduce the detailed near-surface residual stresses found from the finite element model of the cold working process.

Supporting Large-Scale End User Specification of Workflows, Work Coordination and Tool Integration

Workflow Management Systems are a common example of an end user development system, in that they support end user specification of work process models, end user enactment (running) of these models, and end user evolution of workflows. Example applications of Workflow Management Systems include office automation, software process modelling and business process codification. We describe a novel workflow system which provides visual support for end users to specify both simple and complex aspects of workflows, including workflow models, communication and collaboration techniques, and the tools used to perform work. We illustrate both the utility of these work coordination mechanisms and the degree of scalability they provide for both novice and experienced end users. We also outline the architecture of our system, our experiences with this workflow tool, and future research directions in this area.

Contexts, work processes, and workspaces

In this paper a framework for the conceptual modelling of organizational contexts is provided and it is embodied into an extension of the TOSCA organizational handbook. The context of a work process is relevant since the effectiveness of the cooperation among its actors is highly dependent on their awareness of it. It requires, on the one hand, that the context is made available in terms of visibility and/or transparency; on the other, that at any time a selection is made so that only what is relevant to the context is provided, leaving the rest in the background. With respect to the first requirement a model of the organizational context is needed, so that all the information regarding its dimensions can be linked together. With respect to the second requirement, a work process model provides some guidelines for designing a system offering a selective access to the context of a work process. The workspace metaphor is a good paradigm to make that information ready at hand, since it is the natural framework within which people do their work.

HSM-Simulation–Based Planning Method for Construction Projects

Construction projects are characterized by the random nature of the conditions under which they are implemented and by the dynamic use of available resources. Since site conditions vary randomly and resources perform a multitude of functions on various work tasks, planning of construction projects using traditional tools like the critical path method becomes limited and induces deficiency in the resulting plan. This paper demonstrates that a simulation-based methodology is appropriate for modeling such a scenario. The hierarchical simulation modeling (HSM) method, a simulation-based method, for planning of construction projects is presented. HSM enhances and combines the concepts of work breakdown structure and process modeling to arrive at an advanced framework for planning. Hierarchical and modular simulation constructs form the basis of this method. The construction of a bridge (Peace River Bridge) is used to illustrate HSM concepts and its advantages.

Absence behaviour, turnover and disability: A study among city bus drivers in the Netherlands

Abstract Absenteeism, turnover and disability, and relationships between them have been studied among city bus drivers in the Netherlands. The theoretical framework for the study was a cumulative process model of work and health. Absenteeism among these drivers was two to three times as high as the national average, while the risk of disablement was more than twice as high as the risk for male Dutch civil servants in general. Bus drivers who had to leave their job for medical reasons did so at a younger age than other groups of civil servants. The main conditions leading to disablement related to the back, tendons and joints (35%), mental disorders (35%) and cardiovascular diseases (12%). It was shown that long-term absenteeism is a strong precursor of future disability. The research suggests a work-related process of progressive deterioration of health and well-being over a reasonably long period of time. Driving city buses seems to be an occupation with high risks for health and well-being.