Scenario based approach

Scattering techniques, 23 126-127 Scenario analyses, 24 189-190 Scenario-based approach for reliability, 26 1044 in process scheduling, 26 1042-1043 Scenario identification, 13 165 SCH 58235... 

There are two different ways of representing uncertainty. The first approach is the continuous probability distribution where numerical integration is employed over the random continuous probability space. This approach maintains the model size but on the other hand introduces nonlinearities and computational difficulties to the problem. The other approach is the scenario-based approach where the random space is considered as discrete events. The main disadvantage of this approach is the substantial increase in computational requirements with an increase in the number ofuncertain parameters. The discrete distribution with a finite number K of possible... 

A detailed discussion of forecasting techniques is not in the focus of this work (the reader is instead referred to Chase et al. (2006, pp. 510-557), Gunther and Tempelmeier (2005, pp. 142-150), Heizer and Render (2005, pp. 81-118) or Shapiro (2001, pp. 257-261) for overviews on the subject, Hanke and Wichern (2005) for a detailed presentation of different techniques and Haehling von Lanzenauer and Sprung (1982) for a scenario-based approach to forecasting future levels of inflation). However, below a few key aspects of parameterizing the model are discussed. 

The predictive model within the control algorithm consists in a multistage stochastic MILP. A scenario based approach is applied. Refer to Puigjaner and Lainez for scenario tree description and stochastic formulation indices details (1, hi). 

For example, the U.S. Secret Service uses an exhaustive scenario-based approach to protect the President of the United States. Likewise, the nuclear industry uses a rigorous scenario-based approach. In the former case, the symbolic value of a U.S. President makes him or her a very attractive target. In the latter, the political... 

Haumer, P., Heymans, P., Jarke, M., Pohl, K. Bridging the gap between past and future in RE a scenario-based approach. In Proceedings of the 4 International Symposium on Requirements Engineering (RE 99), Limerick, Ireland, pp. 66-73 (1999)... 

Eppen, G.D., Martin, R.K., and Schrage, L.E. A Scenario-Based Approach to Capacity Planning. Operations Research, 37(4) 517—527, July-August 1989. 

Kaindl, H. A Scenario-Based Approach for Requirements Engineering Experience in a Telecommunication Software Development Project. Systems Engineering 8, 197-210 (2005)... 

RISKMAN embodies PLG s scenario-based, engineering-approach displays and calculates event sequence diagrams, fault trees, and event trees. It allows for system-specific data updates and accoums for dependencies between systems. 

Threat assessment has been used as a starting point to define the requirements for a passive defence system. In the past, such requirements were determined on a more or less ad hoc basis. At the TNO Prins Maurits Laboratory we have started a scenario-based systemic approach to model the complete chain of passive defence measures, in order to derive challenge levels and casualty levels. This enables us to study the effects of passive defence requirements upon these levels, thus improving the selection process. 

The quant-based combinatorial optimization differs from classical approaches in a number of ways. First, it is the strength of the quant-based approach to account for all constraints that prevail in a real-life planning scenario. Even though they usually come into effect in complex, interrelated and varying ways. 

There has been a gradual move in environmental policy and regulation from hazard-based to risk-based approaches. This is partly due to the recognition that for many environmental issues a level of zero risk is unobtainable or simply not necessary for human and environmental protection and that a certain level of risk in a given scenario is deemed acceptable after considering the benefits. 

Which employment effects can be listed in the individual sectors are analysed. In an impulse-based approach, the total employment effects are assigned to the economic impulses that trigger them. These impulses consist of the demand shifts triggered by a hydrogen scenario, e.g., the rise in producing hydrogen vehicles on the one hand... 

The relative importance of metabolic transformation of precursor compounds in exposure to PEGS and PFGA has been scarcely evaluated and, to our knowledge, the only study that afforded the problem by a Scenario-Based Risk Assessment (SceBRA) approach estimated the relative importance of precursor-based doses of PEGS and PFGA of 2-5% and 2-8% in an intermediate scenario and 60-80% and 28-55% in a high-exposure scenario. This indicates that these precursors are of low importance for the general population. 

The idea that an inhibitor that binds to a nonenzymatic, nonreceptor site of a virion could inhibit viral replication in vivo would a priori be considered to be an unlikely scenario by most in the field of stmcture-based design. If this idea were proposed knowing only the structure of the native vims (especially HRV14, which has a closed-pocket conformation) skepticism would abound. This type of project arose not from a stmcture-based approach, but from the tried-and-tme screening approach. The compounds were first shown to be effective in inhibiting viral replication in vitro [52]. This was followed by an experiment showing that these compounds could inhibit at least one enterovims in a mouse model [94]. 

An uncertainty analysis gives the assessor the opportunity to re-evaluate the scenario, model approaches and parameters of the analysis and to consider their influence in the overall analysis. The practical impact of uncertainty analysis is illustrated within the annexed case-studies, which also clarify how uncertainty analyses follow a systematic methodology, based on a tiered approach, and consider all possible sources of uncertainty. The first step in uncertainty analysis consists of a screening, followed by a qualitative analysis and two levels of quantitative analysis, using deterministic and probabilistic data. The assessor should be aware that an uncertainty analysis cannot answer all the questions, which, moreover, may lead to new questions. 

Adopt a reasoned view of chemical and biological weapons exposure environments. In the Cold War, massive attack scenarios led to requirements for chemical and biological defense for the Services on the basis of exposures at the point of release (i.e., the highest level). The risk-based approach recommended by the committee ties levels of protection not to the worst case, but to an accep-... 

The possibility of genetically altered agents, which introduces the potential for many more scenarios, suggests that model-based approaches to identify and track biological attacks for estimating who might be exposed will be prudent for some years. 

A scenario-based research approach has been used in IMPROVE in order to identify the requirements, based on a concrete chemical process design case study. A case study from the polymerization domain has been chosen because there are much less mature design support tools as compared to petrochemical processes. Therefore, tool integration and work process support are of considerable interest in both, the end user as well as the software vendor industries. 

Therefore, the project appeared a good place for transferring some of the results of the CRC IMPROVE into industrial practice. In contrast to development processes, these production processes are executed often, and can be measured quantitatively. This allowed the direct application and validation of the approach in real-world processes, instead of scenario-based evaluation as usually utilized when validating design process support. Thus, the aspects of direct experience-based process support as researched by the sub projects BI and Cl, were to be adjusted and applied in the production context. 

The use of antibody- or aptamer-based approaches to protect against ricin holds potential as a possible pretreatment for armed forces, or as an adjunct to PPE for civilian first-responders and other special populations required to enter contaminated areas. However, extracellular antitoxin would probably be of limited use in a bioterrorist or civilian mass casualty scenario, because the therapeutic window for administration is likely to be short (a few hours), the delay to onset of symptoms is relatively long, and there presently is no method of immediately detecting ricin exposure. It also remains to be determined whether specific combinations of MAbs are required for optimal in vivo protection against the toxin. Moreover, in some cases, MAbs that bind toxin with high avidity and block enzymatic activity of RTA in vitro actually enhance the toxicity of ricin in vivo (Maddaloni et al., 2004). 

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