The social foraging behavior of Escherichia coli bacteria has recently been studied by several researchers to develop a new algorithm for distributed optimization control. The Bacterial Foraging Optimization Algorithm (BFOA), as it is called now, has many features analogous to classical Evolutionary Algorithms (EA). Passino [1] pointed out that the foraging algorithms can be integrated in the framework of evolutionary algorithms. In this way BFOA can be used to model some key survival activities of the population, which is evolving. This article proposes a hybridization of BFOA with another very popular optimization technique of current interest called Differential Evolution (DE). The computational chemotaxis of BFOA, which may also be viewed as a stochastic gradient search, has been coupled with DE type mutation and crossing over of the optimization agents. This leads to the new hybrid algorithm, which has been shown to overcome the problems of slow and premature convergence of both the classical DE and BFOA over several benchmark functions as well as real world optimization problems.
A partial order on a bounded lattice L is called t-order if it is defined by means of the t-norm on L. It is obtained that for a t-norm on a bounded lattice L the relation a⪯Tb iff a=T(x,b) for some x∈L is a partial order. The goal of the paper is to determine some conditions such that the new partial order induces a bounded lattice on the subset of all idempotent elements of L and a complete lattice on the subset A of all elements of L which are the supremum of a subset of atoms.
In this paper a fuzzy relation-based framework is shown to be suitable to describe not only knowledge-based medical systems, explicitly using fuzzy approaches, but other ways of knowledge representation and processing. A particular example, the practically tested medical expert system Disco, is investigated from this point of view. The system is described in the fuzzy relation-based framework and compared with CADIAG-II-like systems that are a "pattern" for computer-assisted diagnosis systems based on a fuzzy technology. Similarities and discrepancies in - representation of knowledge, patient's information, inference mechanism and interpretation of results (diagnoses) - of the systems are established. This work can be considered as another step towards a general framework for computer-assisted medical diagnosis.
Lake Lednica, Greater Poland, is one of Poland’s most important and longest-studied underwater archaeological sites. The residential centre established on an island was one of the central points in the state of the first Piasts. Previous research located two bridges to the island and discovered the largest collection of early medieval military objects in Central Europe in the lake. In the 2017 season, a third bridge was discovered on Lake Lednica leading to the small island called Ledniczka on which the layers of an early medieval settlement and clear remnants of a motte-type medieval structure are found. Three seasons of research on relics of the crossing suggest that it may have functioned in two periods: in the tenth century and at the turn of the fourteenth century. During the research, a number of military items, pottery, objects made of organic materials and fishing tools were found. and Lednické jezero ve Velkopolsku patří k nejdůležitějším a nejdéle studovaným lokalitám podvodní archeologie ve střední Evropě. Rezidenční centrum zřízené na zdejším Lednickém ostrově bylo jedním z hlavních míst prvních Piastovců. Předchozí výzkum odhalil dva mosty spojující ostrov s pevninou a největší soubor militárií ze dna středoevropského jezera. V roce 2017 byl identifikován další most, tentokrát zpřístupňující ostrůvek zvaný Ledniczka. Další výzkum ukázal, že most pravděpodobně fungoval ve dvou periodách: v 10. století a na přelomu 13. a 14. století. Přinesl také početný soubor militárií, keramiky, rybářského náčiní a výrobků z organických materiálů. Na ostrůvku byly dokumentovány raně středověké situace a opevnění typu motte.
Utilizing the theory of fixed point index for compact maps, we establish new results on the existence of positive solutions for a certain third order boundary value problem. The boundary conditions that we study are of nonlocal type, involve Stieltjes integrals and are allowed to be nonlinear.
In this paper we present a topological duality for a certain subclass of the Fω-structures defined by M. M. Fidel, which conform to a non-standard semantics for the paraconsistent N. C. A. da Costa logic Cω. Actually, the duality introduced here is focused on Fω-structures whose supports are chains. For our purposes, we characterize every Fω-chain by means of a new structure that we will call down-covered chain (DCC) here. This characterization will allow us to prove the dual equivalence between the category of Fω-chains and a new category, whose objects are certain special topological spaces (together with a distinguished family of open sets) and whose morphisms are particular continuous functions.
We get the following result. A topological space is strongly paracompact if and only if for any monotone increasing open cover of it there exists a star-finite open refinement. We positively answer a question of the strongly paracompact property.
We present various observations of the bipolar nebula No. 14 from the list of Neckel and Staude (1984): CCD images at 7 different wavelengths, spectroscopy at intermediate resolution between 4800 A and 9500 A, and CCD stellar polarimetry. The centra! star turns out to be a "Trapezium" consisting of four stars of spectral types between B0.5 and A5. The nebular spectrum is that of a low
excited HII region, but in addition it exhibits a strong Ol 8446 line excited by Lyman β fluorescence. This requires a very high optical depth in Hα γ ≥ 1000) in the emitting region, which has been spatially resolved in NS 14. The stellar polarimetry, combined with the surface polarimetry of Scarrott et al. (1986), indicates that the polarization in the nebula can be explained by pure scattering
alone.