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Most preferred solution

Finding a final solution to problem (6.1) is called a solution process. It usually involves the DM and an analyst. An analyst can be a human being or a computer program. The analyst s role is to support the DM and generate information for the DM. Let us emphasize that the DM is not assumed to know multi-objective optimization theory or methods but (s)he is supposed to be an expert in the problem domain, that is, understand the application considered and have insight into the problem. Based on that, (s)he is supposed to be able to specify preference information related to the objectives considered and different solutions. The DM can be, e.g., a designer. The task of a multi-objective optimization method is to help the DM in finding the most preferred solution as the final one. The most preferred solution is a Pareto optimal solution which is satisfactory for the DM. [Pg.157]

In reference point based methods, the DM first specifies a reference point z S consisting of desirable aspiration levels for each objective and then this reference point is projected onto the Pareto optimal set. That is, a Pareto optimal solution closest to the reference point is found. The distance can be measured in different ways. Specifying a reference points is an intuitive way for the DM to direct the search of the most preferred solution. It is straightforward to compare the point specified and the solution obtained without artificial concepts. Examples of methods of this t rpe are the reference point method and the light beam search . [Pg.163]

Once the DM has classified the objective functions, (s)he can decide how many Pareto optimal solutions (between one and four) based on this information (s)he wants to see and compare. Then, as many scalarized problems are formed and solved and the new solutions are shown to the DM together with the current solution. If the DM has found the most preferred solution, the solution process stops. Otherwise, the DM can select a solution as a starting point of a new classification or ask for a desired number of intermediate (Pareto optimal) solutions between any two solutions generated so far. The DM can also save any interesting solutions to a database and return to them later. All the solutions considered are Pareto optimal. For details of the algorithm, see Miettinen and Makela (2006). [Pg.167]

The appropriate excitation scheme depends upon the particular FDTD setup. For illustration, when the antenna points at which reflections originate are to be found, a narrow Gaussian pulse could be the most preferable solution. Thus, for a transmitting antenna, the incident voltage in the feeding line is given by... [Pg.190]

Evaluate alternatives and select most preferable solutions with respect to effects on functions, other uses, and life-cycle costs. [Pg.44]

Step 2 Interact with the decision maker to choose the most preferable solution. [Pg.212]

Step 2 Interact with the decision maker to choose the most preferable solution. For an illustrative purpose, suppose a decision maker prefers the third design solution (from the weight sets 2,3, and 6). [Pg.215]

Until recently, for the majority of organizations the most obvious and preferred solution to addressing employee needs was to design and rim classroom-style training courses. [Pg.12]

HCN is the most preferred cyanide source in cyanohydrin synthesis. Besides HCN, several different cyanide sources, like potassium cyanide, are being used in biotransformation. Alternative methods for the safe handling of cyanides on a laboratory scale are, for instance, to use cyanide salts in solution. These solutions can be acidified and used as the aqueous layer in two-phase systems or the HCN can be extracted into the organic layer with the desired solvent for reactions in an organic phase. After the reaction, excess cyanide can readily be destroyed with iron(II) sulfate, or iron(III) chloride or bleach. Cyanide can also be presented in the form of organic cyano, such as acetone cyanohydrin [46] or cyanoformates. However, as claimed by Effenberger, some results could not be reproduced [47]. [Pg.111]

The H2 is separated from C02 and purified at the final stage of the process. Older variations of the SMR process (Figure 2.5a) used solvents to remove the acid gas (C02) from the gaseous stream after WGS reactors. Solvents commercially used for C02 removal in the gas separation unit include monoethanolamine (most preferred and widely used solvent), water, ammonia solutions, potassium carbonate solutions, and methanol. This operation allows the reduction of C02 concentration in the process gas to about 100 ppm. The remaining... [Pg.41]

In theory, once the activity of an electrolyte in solution is known, the activity of the solvent can be determined by the Gibbs-Duhem integration (see section 2.11). In practice, the calculation is prohibitive, because of the chemical complexity of most aqueous solutions of geochemical interest. Semiempirical approximations are therefore preferred, such as that proposed by Helgeson (1969), consisting of a simulation of the properties of the H20-NaCl system up to a solute... [Pg.501]

Catalysis is a valuable and indispensable tool in organic synthesis. Transition metals, most preferably precious metals, are often used. However, potential residual metal contamination from these heterogeneously or homogeneously catalyzed reactions may be detrimental to product quality or, as in the case of active pharmaceutical ingredients (API s), the metal concentration in the final product may be regulated. Degussa s Deloxan Metal Scavengers recover valuable precious metals from reaction mixtures and reduce the metal concentration in process solutions to an acceptable level (<5 ppm). [Pg.493]

I have discussed some of the history of PAC, and some early approaches to its implementation in the petrochemical industry. So, what does it take to Do Process Analysis It takes freedom to try new things with an eye on how it can improve process control in order to make the plant more economical. The dollars drive the technology. Someone, preferably a group, needs to have the freedom to fail because not everything is going to work. This freedom means one tries various approaches looking for the best, most viable solution. Sometimes that solution is the one with which the plant is most... [Pg.10]

Multiple Objective Decision Analysis (MODA) designs the most preferred alternative within a (usually continuous) solution space using a mathematical programming structure to optimize the level of a set of quantifiable objectives. [Pg.128]

We have already discussed the acidity of NH-tetrazoles 61 to form tetrazolate anions 62 [75], In the same paper, we also studied the protonation. The substituent X strongly affects the tautomeric balance between 1,3-H,H+- (82) and 1,4-H,locations (84). In the case of electron-withdrawing substituents, the most preferred form of the conjugated acid is the 1,3-H,H+- form (82) structures 83 and 85 are much less stable. The acidity measures in solution and in the gas phase satisfactorily correlate with each other. In all cases, these relationships do not hold for 5-phenyltetrazole (56, X = Ph). This could be explained by the difference in solvation of this compound compared to other 5-X tetrazoles as well as by some peculiarity of its electronic structure, for example, the strong conjugation between the phenyl substituent and the tetrazole ring. [Pg.166]

Aqueous alcohol iron protoporphyrin solutions with pH > 10 (14 in the limit), required for preventing their interaction with one another, are most frequently used in the synthesis and reactions with biomimics. On the contrary, H202 dissociation was implemented in the presence of 5,10,15,20-tetrakis-(2,6-dimethyl-3-sulfonatophenyl)porphynato-Fe3+ H20 [(P)Fe3+(H20)] in a pH range of between 1 and 12 [65], This porphyrin is easily soluble in water and does not form dimeric and polymeric associates. Of interest are transition states shown in Figure 7.2. It is the author s opinion that the mechanism with heterolytical O—O bond break is the most preferable. [Pg.241]

As outlined by Fosmire and Macklin (2002), the students first task in any PBL setting is to understand the problem and to gain ownership as they, with the help of the instructor, determine what the problem entails. Students then identify what they already know and what they need to know. They then search for information, analyze what they have found, and determine if new issues have been raised. Typically, the students develop a report outlining their preferred solution, but including other potential alternatives. In most cases, the results are reported to the larger class grouping with opportunities for discussion and evaluation of the arguments. [Pg.115]

The Li surface preparation is very important. Immersion of Li electrodes covered by native films leads to complicated surface film replacement processes that may form a highly nonhomogeneous metal-solution interphase. In situ electrochemical surface preparation by dissolution or deposition may form very rough surfaces whose impedance spectra may be difficult to interpret properly. Hence, it seems that the most preferred way of studying the electrochemical behavior of a Li electrode in a specific solution is by using Li surfaces freshly and smoothly prepared in solutions. [Pg.345]


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