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101.
This paper addresses a general multiobjective optimization problem. One of the most widely used methods of dealing with multiple
conflicting objectives consists of constructing and optimizing a so-called achievement scalarizing function (ASF) which has
an ability to produce any Pareto optimal or weakly/properly Pareto optimal solution. The ASF minimizes the distance from the
reference point to the feasible region, if the reference point is unattainable, or maximizes the distance otherwise. The distance
is defined by means of some specific kind of a metric introduced in the objective space. The reference point is usually specified
by a decision maker and contains her/his aspirations about desirable objective values. The classical approach to constructing
an ASF is based on using the Chebyshev metric L
∞. Another possibility is to use an additive ASF based on a modified linear metric L
1. In this paper, we propose a parameterized version of an ASF. We introduce an integer parameter in order to control the degree
of metric flexibility varying from L
1 to L
∞. We prove that the parameterized ASF supports all the Pareto optimal solutions. Moreover, we specify conditions under which
the Pareto optimality of each solution is guaranteed. An illustrative example for the case of three objectives and comparative
analysis of parameterized ASFs with different values of the parameter are given. We show that the parameterized ASF provides
the decision maker with flexible and advanced tools to detect Pareto optimal points, especially those whose detection with
other ASFs is not straightforward since it may require changing essentially the reference point or weighting coefficients
as well as some other extra computational efforts. 相似文献
102.
The activity concentrations and distribution of 210Pb and 210Po in wild berries and edible mushrooms were investigated in Finnish forests. The main study areas were located in Scots pine (Pinus sylvestris L.) forests in southern and northern Finland. The activity concentrations of 210Pb and 210Po in blueberry (Vaccinium myrtillus L.) and lingonberry (Vaccinium vitis-idaea L.) samples decreased in the order: stems > leaves > berries (i.e. fruits). The activity ratios of 210Po/210Pb in the wild berry samples were mainly higher than one, indicating elevated activity concentrations of polonium in the samples. In mushrooms the activity concentrations of 210Pb and especially 210Po were higher than in fruits of the wild berries. The highest activity concentration of 210Pb was detected in Cortinarius armillatus L. (16.2 Bq kg− 1 d.w.) and the lowest in Leccinum vulpinum L. (1.38 Bq kg− 1 d.w.). The 210Po activity concentrations of the whole fruiting bodies ranged from 7.14 Bq kg− 1 d.w. (Russula paludosa L.) to 1174 Bq kg− 1 d.w. (L. vulpinum L.). In general, the highest activity concentrations of 210Po were recorded in boletes. The caps of mushrooms of the Boletaceae family showed higher activity concentrations of 210Po compared to the stipes. In most of the mushrooms analyzed, the activity concentrations of 210Po were higher than those of 210Pb. 210Po and 210Pb dominate the radiation doses received via ingestion of wild berries and mushrooms in northern Finland, while in southern Finland the ingested dose is dominated by 137Cs from the Chernobyl fallout. 相似文献
103.
104.
105.
Adam Macierzanka François Bordron Neil M. Rigby E.N. Clare Mills Martina Lille Kaisa Poutanen Alan R. Mackie 《Food Hydrocolloids》2011
Enzymatic cross-linking is an important method of modifying the structure of food products to control their texture and stability. In this paper we look at the effect that adsorption to the oil–water interface of triglyceride oil-in-water emulsion has on rates of cross-linking of sodium caseinate by microbial transglutaminase. The kinetics of cross-linking has also been assessed for the individual casein proteins within the caseinate. In solution the rates were αs2-casein > β-casein > αs1-casein > κ-casein. This order is not as expected given the rheomorphic nature of the proteins and the number of glutamine and lysine residues in each protein. In particular, the αs1-casein was cross-linked much more slowly than expected. When sodium caseinate was adsorbed to an emulsion the rates for all constituent caseins were decreased but the cross-linking rate for αs1-casein was markedly reduced, indicating the most significant change in accessibility following adsorption. This knowledge will facilitate optimal production of cross-linked emulsions for use in future studies aimed at engineering emulsions with improved nutritional quality. 相似文献
106.
Interactive methods are useful and realistic multiobjective optimization techniques and, thus, many such methods exist. However,
they have two important drawbacks when using them in real applications. Firstly, the question of which method should be chosen
is not trivial. Secondly, there are rather few practical implementations of the methods. We introduce a general formulation
that can accommodate several interactive methods. This provides a comfortable implementation framework for a general interactive
system. Besides, this implementation allows the decision maker to choose how to give preference information to the system,
and enables changing it anytime during the solution process. This change-of-method option provides a very flexible framework
for the decision maker. 相似文献
107.
108.
Riitta Puupponen‐Pimiä Tuulikki Seppänen‐Laakso Matti Kankainen Johanna Maukonen Riitta Törrönen Marjukka Kolehmainen Tiina Leppänen Eeva Moilanen Liisa Nohynek Anna‐Marja Aura Kaisa Poutanen Francisco A. Tómas‐Barberán Juan C. Espín Kirsi‐Marja Oksman‐Caldentey 《Molecular nutrition & food research》2013,57(12):2258-2263
Ellagitannins are polyphenols abundant in strawberries, raspberries, and cloudberries. The effects of a mixture of these berries were studied in a randomized controlled trial with subjects having symptoms of metabolic syndrome. The study focused on serum lipid profiles, gut microbiota, and ellagitannin metabolites. The results indicate that bioavailability of ellagitannins appears to be dependent on the composition of gut microbiota. 相似文献
109.
Aunola Kaisa; Leskinen Esko; Lerkkanen Marja-Kristiina; Nurmi Jari-Erik 《Canadian Metallurgical Quarterly》2004,96(4):699
This study investigated the developmental dynamics of mathematical performance during children's transition from preschool to Grade 2 and the cognitive antecedents of this development. 194 Finnish children were examined 6 times according to their math performance, twice during each year across a 3-year period. Cognitive antecedents, that is, counting ability, visual attention, metacognitive knowledge, and listening comprehension, were tested at the first measurement point. The results indicated that math performance showed high stability and increasing variance over time. Moreover, the growth of math competence was faster among those who entered preschool with an already high level of mathematical skills. The initial level of math performance, as well as its growth, was best predicted by counting ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Non-destructive inspections are performed to give confidence of the non-existence of flaws exceeding a certain safe limit in the inspected structural component. The principal uncertainties related to these inspections are the probability of not detecting an existing flaw larger than a given size, the probability of a false call, and the uncertainty related to the sizing of a flaw. Inspection reliability models aim to account for these uncertainties. This paper presents the analysis of sizing uncertainty of flaws for the results of the NESC III Round Robin Trials on defect-containing dissimilar metal welds. Model parameters are first estimated to characterize the sizing capabilities of various teams. A Bayesian updating of the flaw depth distribution is then demonstrated by combining information from measurement results and sizing performance. 相似文献