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Abstrakt

A transformer is an important part of power transmission and transformation equipment. Once a fault occurs, it may cause a large-scale power outage. The safety of the transformer is related to the safe and stable operation of the power system. Aiming at the problem that the diagnosis result of transformer fault diagnosis method is not ideal and the model is unstable, a transformer fault diagnosis model based on improved particle swarm optimization online sequence extreme learning machine (IPSO-OS-ELM) algorithm is proposed. The improved particle swarmoptimization algorithm is applied to the transformer fault diagnosis model based on the OS-ELM, and the problems of randomly selecting parameters in the hidden layer of the OS-ELM and its network output not stable enough, are solved by optimization. Finally, the effectiveness of the improved fault diagnosis model in improving the accuracy is verified by simulation experiments.
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Abstrakt

Zagraniczne inwestycje wydobywcze są narażone na znaczne ryzyko z powodu różnych czynników mających wpływ na taką działalność. Stosowane wskaźniki często zawierają elementy niepewności i nie można ich w pełni skwantyfikować. Kierując się teorią analizy par (set par analysis), badanie to tworzy system indeksu oceny ryzyka oparty na analizie czynników ryzyka zagranicznych inwestycji górniczych i określa wagi czynników z zastosowaniem entropii. Ponadto w artykule przedstawiono model oceny ryzyka związanego z identyfikacją rozbieżności, oparty na powiązaniu pięciu elementów. Zarówno pewność, jak i niepewność różnych ryzyk są traktowane jednolicie w tym modelu i możliwe jest matematyczne opisanie i ilościowe wyrażenie złożonych decyzji systemowych w celu oceny projektów. Ryzyko inwestycji zagranicznych i ich zmieniające się trendy są oceniane syntetycznie poprzez obliczanie sąsiedniego elementu i analizowanie ustalonego potencjału dla tej pary. Przykładem może być faktyczny zagraniczny projekt inwestycyjny dotyczący górnictwa, gdzie ryzyko inwestycji zagranicznych można podzielić na pięć rodzajów zgodnie z rachunkiem ryzyka, a następnie dokonuje się oceny modelu i uzyskuje się konkretne wyniki oceny ryzyka. Na przykładzie przedstawiono aspekty praktyczne i skuteczność tej metody oceny. Ten nowy model łączy czynniki statyczne i dynamiczne oraz informacje jakościowe i ilościowe, co poprawia wiarygodność i dokładność oceny ryzyka. Co więcej, ta metoda oceny może być również zastosowana do innych podobnych zagadnień i ma pewną skalowalność.
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Abstrakt

The BeiDou navigation satellite system (BDS) is one of the four global navigation satellite systems. More attention has been paid to the positioning algorithm of the BDS. Based on the study on the Kalman filter (KF) algorithm, this paper proposed a novel algorithm for the BDS, named as the minimum dispersion coefficient criteria Kalman filter (MDCCKF) positioning algorithm. The MDCCKF algorithm adopts minimum dispersion coefficient criteria (MDCC) to remove the influence of noise with an alpha-stable distribution (ASD) model which can describe non-Gaussian noise effectively, especially for the pulse noise in positioning. By minimizing the dispersion coefficient of the positioning error, the MDCCKF assures positioning accuracy under both Gaussian and non-Gaussian environment. Compared with the original KF algorithm, it is shown that the MDCCKF algorithm has higher positioning accuracy and robustness. The MDCCKF algorithm provides insightful results for potential future research.
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Abstrakt

The recently proposed q-rung orthopair fuzzy set (q-ROFS) characterized by a membership degree and a non-membership degree is powerful tool for handling uncertainty and vagueness. This paper proposes the concept of q-rung orthopair linguistic set (q-ROLS) by combining the linguistic term sets with q-ROFSs. Thereafter, we investigate multi-attribute group decision making (MAGDM) with q-rung orthopair linguistic information. To aggregate q-rung orthopair linguistic numbers ( q-ROLNs), we extend the Heronian mean (HM) to q-ROLSs and propose a family of q-rung orthopair linguistic Heronian mean operators, such as the q-rung orthopair linguistic Heronian mean (q-ROLHM) operator, the q-rung orthopair linguistic weighted Heronian mean (q-ROLWHM) operator, the q-rung orthopair linguistic geometric Heronian mean (q-ROLGHM) operator and the q-rung orthopair linguistic weighted geometric Heronian mean (q-ROLWGHM) operator. Some desirable properties and special cases of the proposed operators are discussed. Further, we develop a novel approach to MAGDM within q-rung orthopair linguistic context based on the proposed operators. A numerical instance is provided to demonstrate the effectiveness and superiorities of the proposed method.
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Abstrakt

Vaccination is a common routine for prevention and control of human and animal diseases by inducing antibody responses and cell-mediated immunity in the body. Through vaccinations, smallpox and some other diseases have been eradicated in the past few years. The use of a patho- gen itself or a subunit domain of a protein antigen as immunogens lays the basis for traditional vaccine development. But there are more and more newly emerged pathogens which have expe- rienced antigenic drift or shift under antibody selective pressures, rendering vaccine-induced im- munity ineffective. In addition, vaccine development has been hampered due to problems includ- ing difficulties in isolation and culture of certain pathogens and the antibody-dependent enhancement of viral infection (ADE). How to induce strong antibody responses, especially neu- tralizing antibody responses, and robust cell-mediated immune responses is tricky. Here we re- view the progress in vaccine development from traditional vaccine design to reverse vaccinology and structural vaccinology and present with some helpful perspectives on developing novel vac- cines.
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Abstrakt

This communication reports detection of somaclonal variation among tissue culture-raised plants of Amorphophallus rivieri Durieu, an economically important crop in China, with high content of glucomannan in its corms. A population of regenerated plants was obtained from a single donor plant of A. rivieri via corm organogenesis, and 28 plants were randomly selected as a representative sample and subjected to analysis of somaclonal variation using inter-simple sequence repeat (ISSR) markers. Of the 26 ISSR primers screened, 13 gave distinct and reproducible band patterns, yielding 131 bands with an average of 10.1 bands per primer. Ten primers were polymorphic and generated 16 polymorphic bands with 12.2% mean polymorphism. Based on the ISSR data from the regenerated plants and the donor plant, Jaccard's similarity coefficients were calculated; they ranged from 0.961 to 1.000 with a mean of 0.982. A dendrogram was constructed using the unweighted pair group method with arithmetic mean (Upgma); it showed that a majority of regenerated plants (including the donor plant) clustered closely, with a mean similarity coefficient of 0.987. Low somaclonal variation observed in the regenerated plants indicates that rapid propagation of A. rivieri via corm organogenesis is a practicable method with a low risk of genetic instability.
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Abstrakt

Heterogeneous nuclear ribonucleoprotein K (hnRNP K), is a multifunctional protein that participates in a variety of regulatory processes of signal transduction and gene expression. To further characterize the significance of hnRNP K in different male germ cells, we investigated the expression profiles of hnRNP K at different developmental stages in pig and rat testes, and conducted a comparative analysis of expression patterns between these two species. In porcine testis development, both the mRNA and protein level of hnRNP K were down-regulated from 3 months to 8 months. However, the expression level of hnRNP K was abundant across the embryonic period in rats, and decreased gradually from 0 day post partum (dpp) to 14 dpp, then increased with the highest level presenting at 90 dpp. Immunolocalization analysis further confirmed the differential expression and localization of hnRNP K protein during testis development in pigs and rats. The results showed that hnRNP K was widely distributed in gonocytes, spermatogonia, sertoli cells and Leydig cells. The dynamic expression profile of hnRNP K may imply its crucial and potential roles in the development of the testis, which will provide a theoretical basis for the future study of molecular mechanism regulation of spermatogenesis.
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Abstrakt

Objective: This study aimed to investigate developmental changes of the thymus and intra- thymic IL-1β, IL-6 and TNF-α expression in weaned Sprague-Dawley rats induced by lipopolysac- charide. Methods: Forty healthy weaned rats aged 26 days and weighing 83±4 g were randomly and equally divided into two groups. The lipopolysaccharide group was treated daily with a single injection of lipopolysaccharide for 10 consecutive days, and the saline group was treated with an equal volume of sterilized saline. On the 1st, 4th, 7th and 10th day, histological changes and distribu- tion of IL-1β-, IL-6- and TNF-α-positive cells were detected in the thymus by hematoxylin-eosin and immunohistochemistry staining, respectively. Subsequently, the expression levels of IL-1β, IL-6 and TNF-α were evaluated in the thymus by the ELISA method. Results: Thymus weight and index were significantly smaller in lipopolysaccharide-treated rats than in saline-treated rats (p<0.05), but no substantial changes were found in the thymus microstructure after lipopolysaccharide induction. Moreover, a large number of IL-1β-, IL-6- and TNF-α-positive cells were observed with brownish-yellow color and mainly distributed in the thy- mus parenchyma, both integrated optical density and average optical density increased signifi- cantly in lipopolysaccharide-treated rats than those in saline-treated rats. Compared with the saline group, most of the thymic homogenates had higher levels of IL-1β, IL-6 and TNF-α in the lipopolysaccharide group on different days. Conclusion: These findings indicate that the thymus atrophied after lipopolysaccharide induction in weaned Sprague-Dawley rats, and excessive production of intrathymic IL-1β, IL-6 and TNF-α was probably involved in the atrophic process.
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Abstrakt

In this study, two different compositions of submicron-structured titanium (760 nm) and micron-structured chromium (4.66 μm) powders were mixed to fabricate Cr-31.2 mass% Ti alloys by vacuum hot-press sintering. The research imposed various hot-press sintering pressures (20, 35 and 50 MPa), while the sintering temperature maintained at 1250°C for 1 h. The experimental results showed that the optimum parameters of the hot-press sintered Cr-31.2 mass% Ti alloys were 1250°C at 50 MPa for 1 h. Also, the relative density reached 99.94%, the closed porosity decreased to 0.04% and the hardness and transverse rupture strength (TRS) values increased to 81.90 HRA and 448.53 MPa, respectively. Moreover, the electrical conductivity is enhanced to 1.58 × 104 S·cm–1. However, the grain growth generated during the high-temperature and high-pressure of the hot-press sintering process resulted in the grain coarsening phenomenon of the Cr-31.2 mass% Ti alloys after 1250°C hot-press sintering at 50 MPa for 1 h. In addition, the Cr-31.2 mass% Ti alloys were fabricated with the submicron-structured titanium (760 nm) and chromium (588 nm) powders showed more effective compaction than the micron-structured titanium (760 nm) and chromium (4.66 μm) powders did. The closed porosity decreases to 0.02% and the hardness values increase to 83.23 HRA. However, the agglomeration phenomenon of the Cr phase and brittleness of the TiCr2 Laves phases easily led to a slight decrease in TRS (400.54 MPa).
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Abstrakt

The combined effect of sulfur (S) and acid soluble aluminum (Als) content on precipitates and microstructures in grainoriented silicon steel were investigated. The results show that there are dominant AlN and a little amount of MnS-AlN composite in annealed hot-rolled band, and the amount of precipitates increases distinctly with increasing Als content, while S content plays a negligible role. The inhibitors that precipitate during hot band annealing can restrain the grain growth during hot band annealing and primary annealing, and the smaller grains of annealed hot-rolled band can contribute to the formation of {111} <112> texture during primary annealing. Lower S content is conducive to the formation of {111} <112> texture during primary annealing by promoting the formation of Goss texture during hot rolling.
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