Decision human

Landscape Planning and Land-Use Decisions. Human activity, particularly agriculture, mining, and urbanization, can fundamentally alter landscape structure by changing the dominant land cover and use from natural habitats to human-use areas. This changes the spatial patterns of natural landscapes... 

Conventional computers initially were not conceived to handle vague data. Human reasoning, however, uses vague information and uncertainty to come to a decision. In the mid-1960 this discrepancy led to the conception of fuzzy theory [14]. In fuzzy logic the strict scheme of Boolean logic, which has only two statements true and false), is extended to handle information about partial truth, i.e., truth values between "absolutely true" and absolutely false". It thus gives a mathematical representation of uncertainty and vagueness and provides a tool to treat them. 

History. Methods for the fractionation of plasma were developed as a contribution to the U.S. war effort in the 1940s (2). Following pubHcation of a seminal treatise on the physical chemistry of proteins (3), a research group was estabUshed which was subsequendy commissioned to develop a blood volume expander for the treatment of military casualties. Process methods were developed for the preparation of a stable, physiologically acceptable solution of alburnin [103218-45-7] the principal osmotic protein in blood. Eady preparations, derived from equine and bovine plasma, caused allergic reactions when tested in humans and were replaced by products obtained from human plasma (4). Process studies were stiU being carried out in the pilot-plant laboratory at Harvard in December 1941 when the small supply of experimental product was mshed to Hawaii to treat casualties at the U.S. naval base at Pead Harbor. On January 5, 1942 the decision was made to embark on large-scale manufacture at a number of U.S. pharmaceutical plants (4,5). 

On the basis of these differences in species response it was concluded that phthalates do not pose a significant health hazard to humans. This view is home out by the EU Commission decision of July 25, 1990 which states that DEHP shall not be classified or labeled as a carcinogenic or an irritant substance (42). This has been reaffirmed in a comprehensive review (43) which concludes that "peroxisome proliferators constitute a discrete class of nongenotoxic rodent hepatocarcinogens and that the relevance of thek hepatocarcinogenic effects for human hazard assessment is considered to be negligible."... 

To be able to systematically identify opportunities for reducing human error, it is useful to ask the question, What is human error One definition is that human error is an inappropriate or undesirable human decision or behavior that reduces, or has the potential for reducing safety or system performance (Rasmusssen 1979). There is a tendency to view errors as operator errors. However, the error may result from inadequate management, design, or maintenance of the system. This broader view which encompasses the whole system can help provide opportunities for instituting measures to reduce the likelihood of errors. 

Many sophisticated models and correlations have been developed for consequence analysis. Millions of dollars have been spent researching the effects of exposure to toxic materials on the health of animals the effects are extrapolated to predict effects on human health. A considerable empirical database exists on the effects of fires and explosions on structures and equipment. And large, sophisticated experiments are sometimes performed to validate computer algorithms for predicting the atmospheric dispersion of toxic materials. All of these resources can be used to help predict the consequences of accidents. But, you should only perform those consequence analysis steps needed to provide the information required for decision making. 

A valuable QRA result is the importance of various components, human errors, and accident scenarios contributing to the total risk. The risk importance values highlight the major sources of risk and give the decision maker a clear target(s) for redesign or other loss prevention efforts. For example, two accident scenarios may contribute 90% of the total risk once you realize that, it is obvious that you should first focus... 

Where there is an imminent threat to human health and the environment, as well as in some nonemergency situations, the regulatory agency may ascertain that a response is appropriate prior to the completion of the RCRA Facility Investigation or the Corrective Measures Study. Hence, the decision for interim measures can be made based on the immediacy as well as the magnitude of the potential threat to human health or the environment the nature of appropriate Corrective Action the implications of deferring Corrective Action until the RCRA Facility Investigation and Corrective Measure Study is complete and other factors. 

Early in the Corrective Action process, a decision may be made concerning whether or not containment is necessary to protect human health and the environment (HHE). If the release or threatened release presents danger to HHE, immediate action must be taken to halt migration. Under these circumstances, actions termed "Interim Measures" may be required, and excavation or containment measures may be directed by the regulatory agency. However, the Owner/Operator will be responsible for their implementation. In the event that containment is not required as an interim measure, containment may still be needed as part of the overall Corrective Action to halt the pollution migration if wastes or contaminants are to be left on-site. 

The performance of human beings is profoundly influenced by the culture of the organization (see discussion of the right stuff above). Unit/plant/company cultures vary in the degree of decision making by an individual operator. Cultures vary in their approach to the conflict between shutdown for safety versus keep it running at all costs. Personnel in one plant reportedly asked Is it our plant policy to follow the company safety policy In an organization with an inherently safer culture, people would say, "Our plant policy is to follow the company safety policies and standards ... 

Humans control all chemical and nuclear processes, and to some extent all accidents result from human error, if not directly in the accident then in the process design and in the process inadequate design to prevent human error. Some automatic systems such used in nuclear power reactors because the response time required is too short for human decisions. Even in these, human error can contribute to failure by inhibiting the systems. 

Equipment Failures Safety system Ignition Sources Furnaces, Flares, Incinerators, Vehicles, Electrical switches. Static electricity, Hot surfaces. Cigarettes Human Failures Omission, Commission, Fault diagnosis. Decisions Domino Effects Other containment failures. Other material release External Conditions Meteorology, Visibility... 

Hall, R. E. et al., Post-Event Human Decision Errors Operator Action Tree/Time Reliability Correlation, BNL, November 1982. 

This task consists of defining target levels for indoor and outdoor conditions based on requirements for laws and regulations, human health, production processes and equipment, and type of premises and construction. Target levels should also be defined for the ventilation system. For the decision tree, see Fig. 3.6. 

Measures to reduce human error are often implemented at an existing plant, rather than during the design process. The decision to conduct an evaluation of the factors that can affect error potential at an existing plant may be taken for several reasons. If human errors are giving rise to unacceptable safety, quality or production problems, plant management, with the assistance of the workforce, may wish to carry out a general evaluahon or audit of the plant in order to identify the direct causes of these problems. 

The Wickens model suggests that there are finite information-processing or attentional resources available, as represented by the box in Figure 2.2. These resources can be distributed in different ways but cannot be increased. Thus, interpretation of complex or unusual information displayed by the interface will leave fewer resources available for handling the response selection and decision making demands. This provides a theoretical basis for the view of human error described in Section 1.7, which described error as a mismatch between demands and capabilities. 

The following sections discuss how errors can arise at each of the stages of perception, decision-making and control actions. The account given below of how information is processed by the human perceptual system is highly simplified. More technical descriptions are provided in many textbooks, for example, Wickens (1984). 

An automatic control system is often introduced because it appears to do a job better than the human. However, the human is still asked to monitor its effectiveness. It is difficult to see how the worker can be expected to check in real time that the automatic control system is, for example, using the correct rules when making decisions. It is well known that humans are very poor at passive monitoring tasks where they are required to detect and respond to infrequent signals. These situations, called vigilance tasks, have been studied extensively by applied psychologists (see Warm, 1984). On the basis of this research, it is unlikely that people will be effective in the role of purely monitoring an automated system. 

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