Operational scenario analysis

Operational scenario analysis is an analysis that the activities required to be undertaken, can be successfully completed using the manpower and facilities provided for the purpose. 

What-if analysis This program should allow the user to do various studies of plant operating scenarios to ascertain the expected performance level of the plant due to environmental and other operational conditions. 

See also Hazard acceptance Hazard assessment Hazard identification entries limitations of, 13 153-154 probability, 13 166-170 purpose of, 13 152 scenario identification, 13 165 source modeling and consequence modeling, 13 165-166 sustainable development and, 24 183-188 techniques for, 13 152-154 Hazard and operability (HAZOP) analysis, 13 154, 157-159 guide words for, 13 158t sample, 13 159... 

Pure simulation approaches are proposed by Pitty et al. (2008) and Adhitya and Srini-vasan (2010). Pitty et al. (2008) propose a discrete-event simulation model for a refinery supply chain. Operational decisions such as unloading schedules and production planning are made based on simple priority rules. Various configurations of the modelled SC are studied and compared to reveal optimization potentials. This approach explicitly considers some details of ship and pipeline transports. Adhitya and Srinivasan (2010) describe a discrete-event simulation model for an SC producing and distributing lubricant additives. Here, batch production is modelled. Again, operational production decisions are made by priority rules and a scenario analysis is conducted to evaluate the effects of other priority... 

The accident analyses in this SAR will be developed based on the conservative assumption that the entire radiological inventory associated with the number of isotope targets expected to be simultaneously at risk is available in a form which is readily transported, i.e. an ARF of 1.0 will be assumed for all materials. This assumption will apply to the inventory contained in targets which are simultaneously in-process". In-process" is defined as that time during which chemical process operations are being conducted on the material subject to release, up to the point of solidification of process residuals. Once process residuals are solidified, the fission products are In a much less volatile state (see waste accident scenario analysis described in Section 3.4.2.4) and the inventory can essentially be considered to be not at risk. 

Nuclear power plants are often facing situations in which a component or a system is not available or is out of service, and the original design requires de-rating the unit or shutdown within a certain period of time. There is the possibility to evaluate the performance of the unit in a scenario that is not having the component or the affected system out of service, to show that there is not safety impact or to identify the restrictions to be applied in such operational scenario, and by this analysis to apply for a license exception in order to continue in line until the programmed shutdown or when spare parts are available. 

The enterprise analyzes and prioritizes potential functional failure modes to define failure effects and identify the need for fault detection and recovery fimctions. Functional reliability models are established to support the analysis of system effectiveness for each operational scenario. Failures, which represent significant safety, performance, or environmental hazards, are modeled to completely understand system impacts. 

Niunher of scenario analysis of complex operations and percentage of complex operations with... 

Brainstorming, questionnaires, business process studies, industry benchmarking, scenario analysis, risk assessment workshops, incident investigation, auditing, and inspection, HAZOP (HAZard OPerability Studies)... 

Literature on the many techniques for making risk assessments is abundant. For example, in ANSI/ASSE Z690.3. Risk Assessment Techniques, reviews are included of 31 techniques. Examples are Primary Hazard Analysis, Fault Tree Analysis, Hazard and Operably Studies, Bow Tie Analysis, Scenario Analysis, Reliability Centered Maintenance, Markov Analysis, Bayesian Statistics and Bayes nets, and Multi-Criteria Decision Analysis. 

Purohit, G.P., Ellison, J.R., Jaekle, D.E., 1999. Propellant management device analysis for some off-design operational scenarios. In AIAA-99-2974, 35th Joint Propulsion Conference, Los Angeles, CA, June 20-23. 

By means of an analysis against several DRM-related criteria, the DRM project has selected TOPAZ from a list of candidate DRM methods as a suitable solution for the safety risk assessment of ATM operational scenarios. TOPAZ is an agent-based DRM method that uses Monte Carlo simulations and uncertainty evaluations to analyse the safety risk of air traffic operations up to the level of collisions. The project produced guidelines for the application of this method in SESAR context, and applied the method to a SESAR Test Case of Land vs Line-up Conflicting ATC Clearances. 

One of the key issues in initiating the CRIOP analysis has been to select the relevant checklist items and scenarios during the planning and preparation phase. The identified issues should be further explored in the subsequent CRIOP analysis. The scenario analysis is an important arena for exploring challenging situations. Experienced CCR operators should be involved to identify scenarios to be explored. Given the limited time available for a CRIOP analysis, it is important not to include too many questions or too many scenarios. The CRIOP analysis must not be performed as a defence, or... 

The ambient, shaker, and drop weight data from scenario 8 of the progressive damage test have been employed as benchmark data for system identification methods for operational modal analysis. Peeters and Ventura (2003) compare the modal parameter estimates obtained by seven different research teams in the framework of this benchmark. In addition, new modal parameter estimation techniques have been validated on the benchmark data. The best reported result was obtained by applying a subspace identification algorithm (Reynders and De Roeck 2008) and a maximum likelihood algorithm... 

We save the model calibration by clicking Save for Simulation... in the Analysis tab of the Refomer Calibration Environment. Aspen HYSYS will prompt us (see Figure 5.91) to save this calibration as Set-T. We can have multiple calibrations for the same reformer and use different calibrations sets for different operating scenarios. We recommend only having only calibration set per reformer model file. 

Frequency Phase 3 Use Branch Point Estimates to Develop a Ere-quency Estimate for the Accident Scenarios. The analysis team may choose to assign frequency values for initiating events and probability values for the branch points of the event trees without drawing fault tree models. These estimates are based on discussions with operating personnel, review of industrial equipment failure databases, and review of human reliability studies. This allows the team to provide initial estimates of scenario frequency and avoids the effort of the detailed analysis (Frequency Phase 4). In many cases, characterizing a few dominant accident scenarios in a layer of protection analysis will provide adequate frequency information. 

PROBLEM DEFINITION. This is achieved through plant visits and discussions with risk analysts. In the usual application of THERP, the scenarios of interest are defined by the hardware orientated risk analyst, who would specify critical tasks (such as performing emergency actions) in scenarios such as major fires or gas releases. Thus, the analysis is usually driven by the needs of the hardware assessment to consider specific human errors in predefined, potentially high-risk scenarios. This is in contrast to the qualitative error prediction methodology described in Section 5.5, where all interactions by the operator with critical systems are considered from the point of view of their risk potential. 

One of the most noticeable ergonomic deficiencies in both control rooms was the number of panels that had to be scanned and monitored during the scenarios, and the number of rapid actions required at opposite ends of the control room. The need for virtually simultaneous actions and movements would have been discovered and resolved in the design stage had a task analysis and human error analysis been carried out on an emergency operation. 

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