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51.
The article discusses our study of the problem of blurred image regions detection. Proposed are 21 features: 20 based on the discrete wavelet transform and one being a ratio based on a gray-level co-occurrence matrix. Described features are introduced in order to detect blurred segment regardless of the blur type such as background blur, motion blur, or out of focus. Moreover, proposed features are relatively easy to calculate and parallelize. Multilayer perceptron with a backpropagation algorithm is trained on mentioned features. Three approaches are introduced and tested: (1) with nonoverlapping fixed size windows, (2) with nonoverlapping recursively divided windows, and (3) with addition of a morphological closing operator. 相似文献
52.
Damian Przestacki Mateusz Kukliński Aneta Bartkowska 《The International Journal of Advanced Manufacturing Technology》2017,93(9-12):3111-3123
In this study, a nickel-based superalloy, Waspaloy, was laser heat treated with diode laser. Single laser tracks were manufactured with different laser beam power densities between 63 and 331 kW/cm2, and scanning laser beam speed ranged from 5 to 100 m/min. It was found that laser heat treatment of Waspaloy causes decrease in material hardness—the microhardness in laser tracks is about 300 HV0,1 while the microhardness of substrate is ranged from 300 to 600 HV0,1—which is a positive phenomenon for laser-assisted machining of investigated material. Impacts of laser heat treatment parameters on laser tracks properties were identified for obtaining multiple laser tracks with the most homogenous thickness. Moreover, roughness of heated layers was measured to specify surface quality after laser heat treatment. Multiple laser tracks were produced using different scanning laser beam speed and distances between laser tracks ranged from 0.125 to 1 mm. It was found that if scanning laser beam speed is 75 m/min and distance between laser tracks is equal to or lower than 0.25 mm, in microstructures of multiple laser tracks, cracks are occurring. The most suitable laser heat parameters for obtaining heated layers, and which can be used for laser-assisted machining, were identified as laser beam power density 178.3 kW/cm2, scanning laser beam speed 5 m/min, and distance between laser tracks 0.125 mm. 相似文献
53.
Renata Wlodarczyk Aneta Kolary-Zurowska Roberto Marassi Malgorzata Chojak 《Electrochimica acta》2007,52(12):3958-3964
Nafion stabilized inks of Vulcan XC-72 supported platinum (20 wt.%) nanoparticles (Pt/XC-72) were utilized to produce electrocatalytic films on glassy carbon. The catalysts were modified (activated) with phosphododecatungstic acid H3PW12O40 (PW12). Comparison was made to bare (PW12-free) electrocatalytic films. Electroreduction of dioxygen was studied at 25 °C in 0.5 mol dm−3 H2SO4 electrolyte using rotating disk voltammetry. For the same loading of platinum (≈95 μg cm−2) and for the approximately identical distribution of the catalyst, the reduction of oxygen at a glassy carbon electrode modified with the ink containing PW12 proceeded at ca. 30-60 mV more positive potential (depending on the PW12 content), and the system was characterized by a higher kinetic parameter (rate of heterogeneous electron transfer), when compared to the PW12-free electrocatalyst. Gas diffusion electrodes with Pt/XC-72 supported on carbon paper (Pt loading 1 mg cm−2) were also tested. Under the same experimental conditions, while the exchange current density and the total resistance contribution to polarization components, computed from the galvanostatic polarization curves were found to be clearly higher and lower, respectively, for the ink modified with PW12 relative to the unmodified system. The results demonstrate that addition of heteropolytungstatic acid (together with Nafion) enhances the electrocatalytic activity of platinum towards reduction of oxygen. 相似文献
54.
Agata Błachnio Aneta Przepiórka Patrycja Rudnicka 《International journal of human-computer interaction》2013,29(11):775-787
In recent years, Facebook has become the most popular of social networking sites (SNSs). Due to its increasing popularity and rising number of its users, the phenomenon of Facebook has aroused academic interest as well. There has been a growing number of studies on this subject. The aim of this article is to present the main trends in Facebook research and to provide an overview of major empirical findings. Among the most intensively explored topics in Facebook research, studies that concentrate on personality and individual differences among users, the role of self-efficacy, and motivation for using that specific SNS were identified. There is also a growing trend in empirical studies that focuses on testing advanced theoretical models of Facebook usage determinants. Technology acceptance model, presented in this article, is one of the most often used among them. This kind of approach may serve as a suggestion for a methodological conceptualization in the future confirmatory research on Facebook. 相似文献
55.
Aneta Sabuszewska-J
wiak Aron Lukaszuk Marta Janicka-Konik Artur Wdowiak Grzegorz Jakiel 《International journal of molecular sciences》2022,23(10)
Endometrial cancer is the most common malignancy of the female genital tract. Obesity is a strong risk factor for endometrial cancer. Adipose tissue is an active endocrine organ that synthesizes biologically active cytokine peptides, called adipokines. Adiponectin and leptin are the main cytokines of adipose tissue, which may influence the development of metabolic diseases and carcinogenesis. In this scenario, we describe the role of leptin and adiponectin in the development of endometrial cancer. A better understanding of the signalling pathway of these cytokines in endometrial cancerogenesis will provide an opportunity for effective target therapy and may be usable in fertility-sparing treatment. In the future, clinical trials focusing on adipokines, molecular biology, and genetics of the tumour will be needed. 相似文献
56.
Šachlová Šárka Kuchařová Aneta Pertold Zdeněk Přikryl Richard Fridrichová Michaela 《Bulletin of Engineering Geology and the Environment》2017,76(1):133-144
Bulletin of Engineering Geology and the Environment - The alkali silica reaction (ASR), which originates in highly alkaline conditions in concrete where reactive forms of silica are available,... 相似文献
57.
Jakub Sokołowski Piotr Lewandowski Aneta Kiełczewska Stefan Bouzarovski 《Energy Sources, Part B: Economics, Planning, and Policy》2020,15(2):92-112
ABSTRACT Energy poverty is generally caused by having a low income, facing high energy costs, and living in a home with low energy efficiency. Various indicators capture these facets, but there is no consensus which is the best one, or how to combine them. To this aim, we create a multidimensional index that accounts for five dimensions of energy deprivation: two objective indicators of “low income, high costs,” and “high actual cost,” as well as three subjective indicators of “not warm enough home,” “housing faults,” and “bills difficulties.” We define households as poor if at least two forms of deprivation are present. We apply our measure to Poland. In 2017, 10% of households in Poland suffered from multidimensional energy poverty. Households living in buildings built before 1946, households living in rural areas, and households that were dependent on retirement and disability pensions were at the highest risk of multidimensional energy poverty. 相似文献
58.
Molecular Mechanisms of ZC3H12C/Reg-3 Biological Activity and Its Involvement in Psoriasis Pathology
59.
Aneta Jastrzębska Marzanna Kurzawa Anna Piasta Edward Szłyk 《Food Analytical Methods》2012,5(5):1079-1087
A one-dimensional capillary isotachophoretic method in cationic system of the separation has been applied for histamine determination in food samples. The proposed electrolyte system consisted of 0.01 M potassium hydroxide with l-valine to pH = 9.9 as the leading electrolyte and 0.02 M 2-amino-2-hydroxymethyl-propane-1,3-diol adjusted to pH = 8.3 with 0.1 M hydrochloric acid as terminating electrolyte. Proposed method was characterized by linearity range 5–50 mg L−1 and R 2 = 0.9982, accuracy (recoveries ranged from 95% to 102%), detection (2.10 mg L−1), and quantification (7.01 mg L−1) limits. The sample preparation for proposed electrophoretic method included only simple extraction with trichloroacetic acid with filtration and derivatisation stage are avoided. The histamine concentration was determined in meat (turkey, chicken, beef and pork) and meat products (ripened sausage and dry-cured ham), fish (smoked salmon and mackerel), and different kind of mildew and mold ripened cheeses samples. The histamine content ranged from not detected level for fresh meat to 29.63 mg 100 g−1 for cheese samples. The reversed phase HPLC was applied as reference method and the F-Snedecor test and the t test were employed to compare the precision and accuracy of the both methods. Positive correlations were found between the two analytical methods for histamine determination in food products. The obtained results indicate that the proposed electrophoretic method is simple, precise, accurate, and convenient. 相似文献
60.
Jan Oszmiański Paulina Nowicka Miros?awa Teleszko Aneta Wojdy?o Tomasz Cebulak Krzysztof Oklejewicz 《International journal of molecular sciences》2015,16(7):14540-14553
Twenty three different wild blackberry fruit samples were assessed regarding their phenolic profiles and contents (by LC/MS quadrupole time-of-flight (QTOF) and antioxidant activity (ferric reducing ability of plasma (FRAP) and 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS)) by two different extraction methods. Thirty four phenolic compounds were detected (8 anthocyanins, 15 flavonols, 3 hydroxycinnamic acids, 6 ellagic acid derivatives and 2 flavones). In samples, where pressurized liquid extraction (PLE) was used for extraction, a greater increase in yields of phenolic compounds was observed, especially in ellagic acid derivatives (max. 59%), flavonols (max. 44%) and anthocyanins (max. 29%), than after extraction by the ultrasonic technique extraction (UAE) method. The content of phenolic compounds was significantly correlated with the antioxidant activity of the analyzed samples. Principal component analysis (PCA) revealed that the PLE method was more suitable for the quantitative extraction of flavonols, while the UAE method was for hydroxycinnamic acids. 相似文献