Human-Machine System

Risk Homeostasis The theory that an operator will attempt to maintain a stable perception of risk following the implementation of new technology that increases the safety of a human-machine system. The theory predicts that operators will take greater risks where more safety devices are incorporated into the system. 

Step 6. Having identified such structural factors (the real root causes), the model must allow interpretation of these, i.e. it must suggest ways of influencing these factors, to eliminate or diminish error factors and to promote or introduce recovery opportunities in the human-machine systems and indeed in the organisation as a whole. 

Wang et al. (1986) postulate that if the relative contribution of the different cognitive skills towards the performance of a human-machine system can be either known or inferred, then the corresponding subjective assessment of these skills can help in the designing cognitive aids for the human. They developed a fuzzy set approach to formulate a multicriteria decision-making problem to determine whether individuals can prioritize cognitive skills considered important for inspection performance. 

To assess the potential of simulation to answer questions, every potential human performance modeling project should first determine the specific questions that the project is trying to answer. Then conduct a critical assessment of what is important in the human-machine system being modeled. This will define the required content and fidehty of the model. The questions that should be considered about the system include ... 

In modern human-machine systems, task assignments maybe adaptive or blended rather than strictly allocated. The information-processing capabilities of modem machines often includes some form of task knowledge and reasoning capabilities that provide for an adaptive task allocation that shifts the task demands on the basis of contextual variables. Also, in many cases human performance is augmented by (blended with) machine performance to accomplish a given task. 

Task-Technology tradeoffs Task analyses may be performed for systems that have yet to be developed but for which functional and performance requirements have been defined. In these cases, the analysis will be based on the defined requirements combined with data on human performance capacities and available machine technology. These analyses can be used to assess the workload, technology, and performance tradeoffs expected with different human-machine system configurations. 

Application task Refers to the objectives the user is employing the product to accomplish. Human-centered design Human-centered design refers to a philosophy of human-machine system design that places the focus of the design process on the needs of the human who uses the system... 

Hancock, P A., Chignell, M. H. (1987). Adaptive control in human-machine systems. In P. A. Hancock (EAfHuman factors psychology (pp. 305-345). Amsterdam North-HoUand. 

The third theme is the development of new types of human-machine systems incorporating concepts and procedures utilizing virtual reality. The fourth is the development of the concept of an artificial mind. This is an attempt to develop a computer that operates similarly to the way humans think. Artificial intelligence is a well-known example of this development. Further, artificial emotion and motivation may be implemented in computers or artificial neural systems of the future. The fifth theme is engineering psychophysiology. The purpose of this chapter is to introduce the reader to trends in recent engineering psychophysiological efforts in Japan. 

High-Level Task Analysis Using Cognitive Task Analysis in Human-Machine System Design... 

In analysis of cognitive task components, holistic perspectives have moved beyond using CTA alone to more general analyses of cognitive work. Cognitive work analysis (CWA) includes methods to describe and represent the functional work domain applicable to human-machine systems without specifying particular technologies to accomplish the work (Miller 2004, Lintern 2009, Vicente 1999). 

Since the successful use of biomedical products and systems is often critical, it is imperative that designers understand and accommodate the cognitive demands on and abilities of users not only with regard to use of specific tools but the broader activity and work context in which complex human-machine systems operate. This understanding and accommodation is achieved, in part, through the methods described below. 

CWA A family of interrelation methods forming a framework for analyzing the requirements of large human-machine systems Work-domain analysis Organizational coordination Cognitive states, strategies, and modes... 

Liu, Y., Feyen, R., and Tsimhoni, 0.2006. Queuing network-model human processor (QN-MHP) A computational architecture for multitask performance in human-machine systems. ACM Transactions on Computer-Human Interaction 13 1. 

A concept model describes the information entities being processed and activities being performed by the human-machine system. Concept models provide a means of exploring and examining the ways humans and machines can and need to interact to accomplish the purposes of the system as a whole. 

Rasmussen, Jens, and Annelise Mark Pejtersen. 1995. Virtual ecology of work. In An Ecological Approach to Human Machine Systems I A Global Perspective, ed. J. M. Flach, P. A. Hancock, K. Caird, and K. J. cente, 121-156. Hillsdale, NJ Erlbaum. 

Min, D., Chung, Y. and Kim, B. (2001), An evaluation of computerized procedure system in nuclear power plant, Proceedings of IFAC Human-Machine Systems 2001 (in press). 

Human Factors means those biomedical, psychosocial, work place environment, and engineering considerations pertaining to people in a human-machine system. Some of these considerations are allocation of functions, task analysis, human reliability, training requirements. Job performance aiding, personnel qualification and selection, staffing requirements, procedures, organizational effectiveness, and workplace environmental conditions. 

Human Factors Engineering means the application of knowledge about human performance capabilities and behavioral principles to the design, operation, and maintenance of human-machine systems so that personnel can function at their optimum... 

Aviation maintenance human reliability and associated aircraft airworthiness have been the focus of many philosophies and research works previously. Reason (2003) discussed the human variability paradox when this variability acts - within complex human-machine systems - both as source of error and a vital system defence. He thus questioned How can we limit one while still promoting the other In the same orientation, Hollnagel (2007) showed that risk and safety are, by definitions, always linked together. He gave the notion Risk - - barriers = Safety calling for higher safety acquirement through risk elimination. 

The proper acquisition of relevant information about a task in a safety-critical environment is the foundation of every sound human factors analysis. The scope of the analysis may cover a Human Rehahility Assessment, an evaluation of a human-machine system, the writing of a procedure or the preparation of a training program. 

The most notable change in recent years is the increase in female soldiers for example, 8.2% of the British Army are women and 71% of British Army roles are open to women (UK Ministry of Defence, 2009). In addition, there is evidence that the physical size of personnel is also changing (Pringle et al., 2007). LCS has traditionally adapted to the size and shape of users through the use of textiles, which can be made up into flexible and pliable three-dimensional shapes. The interaction between LCS and humans is, however, more complex, being dependent on adjustment of straps, correct load placement, and biophysical and cognitive makeup of the user. Figure 13.1 shows how an LCS-human machine system can be represented within the soldier system and work environment (adapted from Sanders and McCormick, 1993). 

Safety and risk management research in healthcare has adopted as its dominant trend the systems oriented approach, modelled largely on previous research in safely critical industries such as aviation and nuclear power. The systems view entails that the focus is not primarily on the mechanisms of individual human error but on the factors that shape human performance (Rasmussen 1986 Reason 1993,1997). In an organisational context, such factors are, of course, those that are within the control of the organisation. For instance, it has been suggested that quahty and safety are affected not only by operators professional and technical competence and skills, but also by their attitudes to and perceptions of their job roles, their organisation and management (Helmreich and Merritt 1998). Such employee attitudes and views are important elements which shape safety cirlture - and its related notion safety climate . Indeed, survey studies have shown that staff attitudes are important indices of safety performance not only in human-machine system domains such as railway operations and constmction (e.g. Itoh and Andersen 1999 Itoh et al. 2004 Silva et al. 2004) but also in healthcare (e.g. Colla et al. 2005 Itoh and Andersen 2010). 

Shazia K. and Imran S. B., "Clinical decision support system based virtual telemedicine," Third International Conference on Intelligent Human-Machine Systems and Cybernetics,... 

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