831 research outputs found

    Assessment of Sustainable Development

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    The objective of this paper is to introduce fuzzy set theory and develop fuzzy mathematical models to assess sustainable development based on context-dependent economic, ecological, and societal sustainability indicators. Membership functions are at the core of fuzzy models, and define the degree to which indicators contribute to development. Although a decision-making process regarding sustainable development is subjective, fuzzy set theory links human expectations about development, expressed in linguistic propositions, to numerical data, expressed in measurements of sustainability indicators. In the future, practical implementation of such models will be based on elicitation of expert knowledge to construct a membership function. The fuzzy models developed in this paper provide a novel approach to support decisions regarding sustainable development.agriculture;assessment;fuzzy set theory;sustainable development

    Eliciting Expert Knowledge for Fuzzy Evaluation of Agricultural Production Systems

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    Public concern nowadays is an important frame of reference for thedevelopment of agricultural production systems. The development ofsuch systems, therefore, involves both society level and productionsystem level. Following Zadeh's principle of incompatibility,information obtained at production system level is interpreted atsociety level in linguistic terms. Fuzzy models promise to be avaluable tool as they link measurable information to linguisticinterpretation using membership functions. The objective of this paperis to outline a procedure which deals with criticism regarding theinherent subjectivity in the construction of membership functions whenusing expert knowledge. The procedure guarantees the selection ofappropriate expert knowledge, and provides a guideline supporting theselection of methods to elicit expert knowledge and constructmembership functions. Also on the basis of the results in anillustrative example, it is concluded that the procedure outlined inthis paper suitably deals with criticism regarding membershipfunctions and, therefore, enables a practical implementation of fuzzyevaluation of agricultural production systems. Current researchimplements the procedure to build a fuzzy model which evaluates eggproduction systems in relation to public concern about the welfare oflaying hens.evaluation;subjectivity;expert knowledge;fuzzy models;knowledge elicitation

    Production of organic seeds: Status, Challenges and Prospects

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    General article on the requirements of organic agriculture for seed production. Beside this the organic agricultural system has other demands for organic seed since it does not use chemical control measures and uses natural fertilizers instead of chemical fertilizers. Research can offer an important contribution in the production of seed without diseases

    Assessment of Sustainable Development

    Get PDF
    The objective of this paper is to introduce fuzzy set theory and develop fuzzy mathematical models to assess sustainable development based on context-dependent economic, ecological, and societal sustainability indicators. Membership functions are at the core of fuzzy models, and define the degree to which indicators contribute to development. Although a decision-making process regarding sustainable development is subjective, fuzzy set theory links human expectations about development, expressed in linguistic propositions, to numerical data, expressed in measurements of sustainability indicators. In the future, practical implementation of such models will be based on elicitation of expert knowledge to construct a membership function. The fuzzy models developed in this paper provide a novel approach to support decisions regarding sustainable development

    Eliciting Expert Knowledge for Fuzzy Evaluation of Agricultural Production Systems

    Get PDF
    Public concern nowadays is an important frame of reference for the development of agricultural production systems. The development of such systems, therefore, involves both society level and production system level. Following Zadeh's principle of incompatibility, information obtained at production system level is interpreted at society level in linguistic terms. Fuzzy models promise to be a valuable tool as they link measurable information to linguistic interpretation using membership functions. The objective of this paper is to outline a procedure which deals with criticism regarding the inherent subjectivity in the construction of membership functions when using expert knowledge. The procedure guarantees the selection of appropriate expert knowledge, and provides a guideline supporting the selection of methods to elicit expert knowledge and construct membership functions. Also on the basis of the results in an illustrative example, it is concluded that the procedure outlined in this paper suitably deals with criticism regarding membership functions and, therefore, enables a practical implementation of fuzzy evaluation of agricultural production systems. Current research implements the procedure to build a fuzzy model which evaluates egg production systems in relation to public concern about the welfare of laying hens

    Shift in critical temperature for random spatial permutations with cycle weights

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    We examine a phase transition in a model of random spatial permutations which originates in a study of the interacting Bose gas. Permutations are weighted according to point positions; the low-temperature onset of the appearance of arbitrarily long cycles is connected to the phase transition of Bose-Einstein condensates. In our simplified model, point positions are held fixed on the fully occupied cubic lattice and interactions are expressed as Ewens-type weights on cycle lengths of permutations. The critical temperature of the transition to long cycles depends on an interaction-strength parameter α\alpha. For weak interactions, the shift in critical temperature is expected to be linear in α\alpha with constant of linearity cc. Using Markov chain Monte Carlo methods and finite-size scaling, we find c=0.618±0.086c = 0.618 \pm 0.086. This finding matches a similar analytical result of Ueltschi and Betz. We also examine the mean longest cycle length as a fraction of the number of sites in long cycles, recovering an earlier result of Shepp and Lloyd for non-spatial permutations.Comment: v2 incorporated reviewer comments. v3 removed two extraneous figures which appeared at the end of the PDF

    The effect of α-, β-and γ-cyclodextrin on wheat dough and bread properties

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    Cyclodextrins (CDs) are cyclic oligosaccharides that have found widespread application in numerous fields. CDs have revealed a number of various health benefits, making them potentially useful food supplements and nutraceuticals. In this study, the impact of α-, β-, and γ-CD at different concentrations (up to 8% of the flour weight) on the wheat dough and bread properties were investigated. The impact on dough properties was assessed by alveograph analysis, and it was found that especially β-CD affected the viscoelastic properties. This behavior correlates well with a direct interaction of the CDs with the proteins of the gluten network. The impact on bread volume and bread staling was also assessed. The bread volume was in general not significantly affected by the addition of up to 4% CD, except for 4% α-CD, which slightly increased the bread volume. Larger concentrations of CDs lead to decreasing bread volumes. Bread staling was investigated by texture analysis and low field nuclear magnetic resonance spectroscopy (LF-NMR) measurements, and no effect of the addition of CDs on the staling was observed. Up to 4% CD can, therefore, be added to wheat bread with only minor effects on the dough and bread properties

    Combinatorial Markov chains on linear extensions

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    We consider generalizations of Schuetzenberger's promotion operator on the set L of linear extensions of a finite poset of size n. This gives rise to a strongly connected graph on L. By assigning weights to the edges of the graph in two different ways, we study two Markov chains, both of which are irreducible. The stationary state of one gives rise to the uniform distribution, whereas the weights of the stationary state of the other has a nice product formula. This generalizes results by Hendricks on the Tsetlin library, which corresponds to the case when the poset is the anti-chain and hence L=S_n is the full symmetric group. We also provide explicit eigenvalues of the transition matrix in general when the poset is a rooted forest. This is shown by proving that the associated monoid is R-trivial and then using Steinberg's extension of Brown's theory for Markov chains on left regular bands to R-trivial monoids.Comment: 35 pages, more examples of promotion, rephrased the main theorems in terms of discrete time Markov chain

    Collective excitations of a two-dimensional interacting Bose gas in anti-trap and linear external potentials

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    We present a method of finding approximate analytical solutions for the spectra and eigenvectors of collective modes in a two-dimensional system of interacting bosons subjected to a linear external potential or the potential of a special form u(x,y)=μucosh2x/lu(x,y)=\mu -u \cosh^2 x/l, where μ\mu is the chemical potential. The eigenvalue problem is solved analytically for an artificial model allowing the unbounded density of the particles. The spectra of collective modes are calculated numerically for the stripe, the rare density valley and the edge geometry and compared with the analytical results. It is shown that the energies of the modes localized at the rare density region and at the edge are well approximated by the analytical expressions. We discuss Bose-Einstein condensation (BEC) in the systems under investigations at T0T\ne 0 and find that in case of a finite number of the particles the regime of BEC can be realized, whereas the condensate disappears in the thermodynamic limit.Comment: 10 pages, 2 figures include
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