21 research outputs found

    k-Spectra of weakly-c-Balanced Words

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    A word uu is a scattered factor of ww if uu can be obtained from ww by deleting some of its letters. That is, there exist the (potentially empty) words u1,u2,...,unu_1,u_2,..., u_n, and v0,v1,..,vnv_0,v_1,..,v_n such that u=u1u2...unu = u_1u_2...u_n and w=v0u1v1u2v2...unvnw = v_0u_1v_1u_2v_2...u_nv_n. We consider the set of length-kk scattered factors of a given word w, called here kk-spectrum and denoted \ScatFact_k(w). We prove a series of properties of the sets \ScatFact_k(w) for binary strictly balanced and, respectively, cc-balanced words ww, i.e., words over a two-letter alphabet where the number of occurrences of each letter is the same, or, respectively, one letter has cc-more occurrences than the other. In particular, we consider the question which cardinalities n= |\ScatFact_k(w)| are obtainable, for a positive integer kk, when ww is either a strictly balanced binary word of length 2k2k, or a cc-balanced binary word of length 2kc2k-c. We also consider the problem of reconstructing words from their kk-spectra

    Application of Structural Entropy and Spatial Filling Factor in Colonoscopy Image Classification

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    For finding colorectal polyps the standard method relies on the techniques and devices of colonoscopy and the medical expertise of the gastroenterologist. In case of images acquired through colonoscopes the automatic segmentation of the polyps from their environment (i.e., from the bowel wall) is an essential task within computer aided diagnosis system development. As the number of the publicly available polyp images in various databases is still rather limited, it is important to develop metaheuristic methods, such as fuzzy inference methods, along with the deep learning algorithms to improve and validate detection and classification techniques. In the present manuscript firstly a fuzzy rule set is generated and validated. The former process is based on a statistical approach and makes use of histograms of the antecedents. Secondly, a method for selecting relevant antecedent variables is presented. The selection is based on the comparision of the histograms computed from the measured values for the training set. Then the inclusion of the Rényi-entropy-based structural entropy and the spatial filling factor into the set of input variables is proposed and assessed. The beneficial effect of including the mentioned structural entropy of the entropies from the hue and saturation (H and S) colour channels resulted in 65% true positive and 60% true negative rate of the classification for an advantageously selected set of antecedents when working with HSV images

    Enhancing ultrafiltration performance for dairy wastewater treatment using a 3D printed turbulence promoter

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    Dairy factories annually generate an increasing amount of wastewater, which can cause eutrophication due to high concentrations of amino acids and lipids. To address this issue, membrane technology has emerged as a promising solution, but membrane fouling remains a significant challenge, since it can cause decreased flux, decrease membrane rejection performance, and increased energy demand. This study aimed to reduce membrane fouling by integrated a three-dimensional printed (3DP) turbulence promoter into an ultrafiltration dead-end cell and varying stirring speeds. Two mathematical models, Hermia and resistance-in-series, were used to analyze the fouling process. According to both models, the cake layer formation model indicated the most prevalent fouling mechanism. Specific energy demand, permeate flux, membrane rejection, and membrane reversible and irreversible resistances were measured, calculated, and compared. The results suggest that the combination of an integrated 3DP turbulence promoter and high stirring speeds can effectively reduce membrane fouling in a dairy wastewater treatment module

    Pressure dependence of the spin gap in BaVS_3

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    We carried out magnetotransport experiments under hydrostatic pressure in order to study the nature of the metal-insulator transition in BaVS3_3. Scaling relations for ρ(T,H,p)\rho(T,H,p) are established and the pressure dependence of the spin gap is determined. Our new results, in conjunction with a re-analysis of earlier specific heat and susceptibility data, demonstrate that the transition is weakly second order. The nature of the phase diagram in the TT--pp--HH space is discussed.Comment: 5 pages, 5 figures, submitted to PRB Rap. Co

    Enhancing ultrafiltration performance for dairy wastewater treatment using a 3D printed turbulence promoter

    Get PDF
    Dairy factories annually generate an increasing amount of wastewater, which can cause eutrophication due to high concentrations of amino acids and lipids. To address this issue, membrane technology has emerged as a promising solution, but membrane fouling remains a significant challenge, since it can cause decreased flux, decrease membrane rejection performance, and increased energy demand. This study aimed to reduce membrane fouling by integrated a three-dimensional printed (3DP) turbulence promoter into an ultrafiltration dead-end cell and varying stirring speeds. Two mathematical models, Hermia and resistance-in-series, were used to analyze the fouling process. According to both models, the cake layer formation model indicated the most prevalent fouling mechanism. Specific energy demand, permeate flux, membrane rejection, and membrane reversible and irreversible resistances were measured, calculated, and compared. The results suggest that the combination of an integrated 3DP turbulence promoter and high stirring speeds can effectively reduce membrane fouling in a dairy wastewater treatment module

    Comparison of mtDNA haplogroups in Hungarians with four other European populations: A small incidence of descents with Asian origin

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    Hungarians are unique among the other European populations because according to history, the ancient Magyars had come from the eastern side of the Ural Mountains and settled down in the Carpathian basin in the 9th century AD. Since variations in the human mitochondrial genome (mtDNA) are routinely used to infer the histories of different populations, we examined the distribution of restriction fragment length polymorphism (RFLP) sites of the mtDNA in apparently healthy, unrelated Hungarian subjects in order to collect data on the genetic origin of the Hungarian population. Among the 55 samples analyzed, the large majority belonged to haplogroups common in other European populations, however, three samples fulfilled the requirements of haplogroup M. Since haplogroup M is classified as a haplogroup characteristic mainly for Asian populations, the presence of haplogroup M found in approximately 5% of the total suggests that an Asian matrilineal ancestry, even if in a small incidence, can be detected among modern Hungarians
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