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Objectives deterministic methods

Stochastic methods do not need auxiliary information, such as derivatives, in order to progress. They only require an objective function for the search. This means that stochastic methods can handle problems in which the calculation of the derivatives would be complex and cause deterministic methods to fail. [Pg.40]

Deterministic/Probabilistic techniques A deterministic method classifies an object in one and only one of the training classes and the degree of reliability of this decision is not measured. Probabilistic methods provide an estimate of the reliability of the classification decision. KNN, MLP, SVM and CAIMAN are deterministic. Other techniques, including some kind of ANN are probabilistic (e.g., PNN where a Bayesian decision is implemented). [Pg.31]

Methods for solving optimization problems can be classified into two main types namely, deterministic and stochastic. Deterministic methods often require derivatives of objective... [Pg.108]

The formulation of the batch plant retrofit problem generally involves either deterministic methods based on mathematical programming such as LP (Linear Programming), NLP (Non-Linear Programming), MILP or MINLP or stochastic ones such as evolutionary algorithms. The non-linearity aspect may result from the nature of the constraints and/or the objective function. The mixed feature means that continuous and integer variables are involved in the formulation. [Pg.238]

The objective of the review of the deterministic safety analysis is to determine to what extent the existing deterministic safety analysis remains valid when the following aspects have been taken into account actual plant design the actual condition of SSCs and their predicted state at the end of the period covered by the PSR current deterministic methods and current safety standards and knowledge. In addition, the review should also identify any weaknesses relating to the application of the defence in depth concept. [Pg.13]

In the last twenty years, various non-deterministic methods have been developed to deal with optimum design under environmental uncertainties. These methods can be classified into two main branches, namely reliability-based methods and robust-based methods. The reliability methods, based on the known probabiUty distribution of the random parameters, estimate the probability distribution of the system s response, and are predominantly used for risk analysis by computing the probability of system failure. However, variation is not minimized in reliability approaches (Siddall, 1984) because they concentrate on rare events at the tail of the probability distribution (Doltsinis and Kang, 2004). The robust design methods are commonly based on multiobjective minimization problems. The are commonly indicated as Multiple Objective Robust Optimization (MORO) and find a set of optimal solutions that optimise a performance index in terms of mean value and, at the same time, minimize its resulting dispersion due to input parameters uncertainty. The final solution is less sensitive to the parameters variation but eventually maintains feasibility with regards probabilistic constraints. This is achieved by the optimization of the design vector in order to make the performance minimally sensitive to the various causes of variation. [Pg.532]

A6. As stated in para. A3, the attaiiunent of the safety objectives for a particular nuclear installation is demonstrated by means of a safety analysis. Ideally, diis safety analysis should include all events, sequences and processes where failures or combi-rratiorts of feiluies could potentially have radiological cortsequences. In practical aj licatiorrs, it is not possible or necessary to achieve this degree of completeness. Whedier the safety analysis is carried out by probabilistic methods or by the conventional methods of detailed engineering analyses (deterministic methods) it will, of necessity, be based on a selected set of scenarios (combinations of events, sequences and processes). The selection must be made in such a way that the major contributors to risk are covered as far as is reasonably achievable. Safety analysis, i.e. the demonstration that the types of risks to be considered have been reduced to tolerable levels, as discussed in para. A3, should be performed using proven methods and with appropriate peer review. [Pg.32]

A7. The deterministic methods for safety analysis start by specifying scenarios in terms of initiating events and the component feilures that are assumed to occur. The scenarios are specified to include even remotely likely evmits, and acceptance criteria (including safety margins) are specified in such a way that the end result will meet the national safety objectives. [Pg.32]

The combination of deterministic and probabilistic procedures in the evaluation of plant safety has been realized in the "approach oriented to safety objectives". This method verifies plant safety via the achievement of so-called "safety objectives". The standard to be issued by the German Nuclear Technology Committee, "KTA 2000", intends to establish the framework conditions for such an approach oriented to safety objectives. In Bavaria, this approach has already been applied to all nuclear power stations during periodical safety inspections (PSI). [Pg.144]

Optimisation methods that rely solely on the available information about the response surface of the optimised function, with no randomness involved, are referred to as deterministic. From the overall perspective of function optimisation, the wide variety of such methods means that they are more frequently used than stochastic methods (Floudas, 2000 Snyman, 2005). In such methods, the same starting location of the optimisation procedure always leads to iterating through the same locations in the input space of the objective functions. Before we discuss the role of deterministic methods in the optimisation of catalytic materials, it should be recalled that according to the information they use, all such methods can be divided into three large groups ... [Pg.33]

The SAP contain deterministic (engineering) and probabilistic principles and include numerical criteria. Engineering (deterministic) principles are those good practices which lead to a robust, fault tolerant plant based on sound safety concepts they comprise about 75% of the SAPs. Probabilistic methods are the use of quantitative methods to seek out weakness and to demonstrate the achievement of certain numerical objectives. Deterministic and probabilistic principles complement one another. [Pg.45]

We start with continuous variable optimization and consider in the next section the solution of NLP problems with differentiable objective and constraint functions. If only local solutions are required for the NLP problem, then very efficient large-scale methods can be considered. This is followed by methods that are not based on local optimality criteria we consider direct search optimization methods that do not require derivatives as well as deterministic global optimization methods. Following this, we consider the solution of mixed integer problems and outline the main characteristics of algorithms for their solution. Finally, we conclude with a discussion of optimization modeling software and its implementation on engineering models. [Pg.60]

Parametric population methods also obtain estimates of the standard error of the coefficients, providing consistent significance tests for all proposed models. A hierarchy of successive joint runs, improving an objective criterion, leads to a final covariate model for the pharmacokinetic parameters. The latter step reduces the unexplained interindividual randomness in the parameters, achieving an extension of the deterministic component of the pharmacokinetic model at the expense of the random effects. Recently used individual empirical Bayes estimations exhibit more success in targeting a specific individual concentration after the same dose. [Pg.313]

The coherency matrix method permits the so-called dominant type of deterministic polarization transformation i.e., the corresponding deterministic part, Mueller-Jones matrix, of the initial Mueller matrix. A Jones matrix J is a 2x2 complex valued matrix containing generally eight independent parameters from the real and imaginary parts for each the four matrix elements, or seven parameters if the absolute (isotropic) phase which is not of interest for polarizations is excluded. Every Jones matrix can be transformed into an equivalent Mueller matrix but the converse assertion is not necessarily true. Between Jones J and Mueller Mj matrices that describe deterministic objects there exist a one-to-one correspondence ... [Pg.247]

The main objective of the study is the abUily to analyze an identified model in identifying automaton models from observations. We want to take an established method to learn a DFA and apply it to our timed sequences. Our problem could be modelled as a timed-state transition graph, a probabilistic deterministic finite automaton (PDFA) taking into account timed-event. We also have a set of positive timed-strings (or time-stamped event sequences). [Pg.95]


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