23 research outputs found

    Structural Damage Identification of Pipe Based on GA and SCE-UA Algorithm

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    Structure of offshore platform is very huge, which is easy to be with crack caused by a variety of environmental factors including winds, waves, and ice and threatened by some unexpected factors such as earthquake, typhoon, tsunami, and ship collision. Thus, as a main part of the jacket offshore platform, pipe is often with crack. However, it is difficult to detect the crack due to its unknown location. Genetic algorithm (GA) and SCE-UA algorithm are used to detect crack in this paper, respectively. In the experiment, five damages of the pipe in the platform model can be intelligently identified by genetic algorithm (GA) and SCE-UA. The network inputs are the differences between the strain mode shapes. The results of the two algorithms for structural damage diagnosis show that both of the two algorithms have high identification accuracy and good adaptability. Furthermore, the error of SCE-UA algorithm is smaller. The results also suggest that the structural damage of pipe can be identified by intelligent algorithm

    Comprehensive Water Inrush Risk Assessment Method for Coal Seam Roof

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    In order to prevent coal mine water inrush accidents, it is necessary to appropriately assess the water abundance of coal mines based on drilling and geophysical data. This paper studied a comprehensive risk assessment method of water inrush. First, a water inrush risk index was proposed based on the analytic hierarchy process-entropy method (AHP-EM) and the water-rich structure index was proposed based on the geological data coupled calculation, then weighted two indices above which established the comprehensive water inrush risk assessment method. Secondly, eight factors were chosen as risk control factors of water inrush: core recovery, aquifer thickness, distance from the indirect aquifer to the coal seam, aquiclude thickness, height of water-conducting fracture zone, sand-mud ratio, total layers of aquifer and aquiclude, and the equivalent thickness of sandstone. Finally, the No. 2 coal seam of Dahaize coal mine was taken as the research object, the factors were calculated, and a comprehensive water inrush assessment model was constructed. With site investigation and observation, the water inrush risk assessment model of the No.2 coal seam roof is consistent with the actual mining situation, which verifies the validity of the model. In addition, this method was used to evaluate the water-richness of the weathered bedrock fractured aquifer in the Zhangjiamao coal mine. The practical application of the two mines has verified the generality of the approach. The research could provide scientific assistance for mine water hazard mitigation and mining safety

    Design and Implementation of Online Management System forStudents' Fourth Class Credits

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    Since the concept of the Fourth Class (Comprehensive quality ability teaching) has been presented, the results of the Fourth Class have been enormous. How to manage information informatization is an urgent problem to be solved. This paper uses the mature management system technology to informatize the Fourth Class management

    Design and Implementation of Online Management System forStudents' Fourth Class Credits

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    Since the concept of the Fourth Class (Comprehensive quality ability teaching) has been presented, the results of the Fourth Class have been enormous. How to manage information informatization is an urgent problem to be solved. This paper uses the mature management system technology to informatize the Fourth Class management

    Strain-Controlled Fatigue Behavior and Microevolution of 316L Stainless Steel under Cyclic Shear Path

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    Based on the twin bridge shear specimen, the cyclic shear experiments were performed on 1.2 mm thin plates of 316L metastable austenitic stainless steel with different strain amplitudes from 1 to 5% at ambient temperature. The fatigue behavior of 316L stainless steel under the cyclic shear path was studied, and the microscopic evolution of the material was analyzed. The results show that the cyclic stress response of 316L stainless steel exhibited cyclic hardening, saturation and cyclic softening, and the fatigue life is negatively correlated with the strain amplitude. The microstructure was analyzed by using electron back-scattered diffraction (EBSD). It was found that grain refinement and martensitic transformation during the deformation process led to rapid crack expansion and reduced the fatigue life of 316L

    Direct Index Method of Beam Damage Location Detection Based on Difference Theory of Strain Modal Shapes and the Genetic Algorithms Application

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    Structural damage identification is to determine the structure health status and analyze the test results. The three key problems to be solved are as follows: the existence of damage in structure, to detect the damage location, and to confirm the damage degree or damage form. Damage generally changes the structure physical properties (i.e., stiffness, mass, and damping) corresponding with the modal characteristics of the structure (i.e., natural frequencies, modal shapes, and modal damping). The research results show that strain mode can be more sensitive and effective for local damage. The direct index method of damage location detection is based on difference theory, without the modal parameter of the original structure. FEM numerical simulation to partial crack with different degree is done. The criteria of damage location detection can be obtained by strain mode difference curve through cubic spline interpolation. Also the genetic algorithm box in Matlab is used. It has been possible to identify the damage to a reasonable level of accuracy

    Genomic in situ hybridization identifies parental chromosomes in hybrid scallop (Bivalvia, Pectinoida, Pectinidae) between female Chlamys farreri and male Argopecten irradians irradians

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    Interspecific crossing was artificially carried out between Chlamys farreri (Jones & Preston, 1904) ♀ and Argopecten irradians irradians (Lamarck, 1819) ♂, two of the dominant cultivated scallop species in China. Genomic in situ hybridization (GISH) was used to examine the chromosome constitution and variation in hybrids at early embryonic stage. The number of chromosomes in 66.38% of the metaphases was 2n = 35 and the karyotype was 2n = 3 m + 5 sm + 16 st + 11 t. After GISH, two parental genomes were clearly distinguished in hybrids, most of which comprised 19 chromosomes derived from their female parent (C. farreri) and 16 chromosomes from their male parent (A. i. irradians). Some chromosome elimination and fragmentation was also observed in the hybrids

    Chromosomal mapping of tandem repeats in the Yesso Scallop, Patinopecten yessoensis (Jay, 1857), utilizing fluorescence in situ hybridization

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    Construction of cytogenetic maps can provide important information for chromosome identification, chromosome evolution and genomic research. However, it hasn’t been conducted in many scallop species yet. In the present study, we attempted to map 12 fosmid clones containing tandem repeats by fluorescence in situ hybridization (FISH) in the Yesso scallop Patinopecten yessoensis (Jay, 1857). The results showed 6 fosmid clones were successfully mapped and distributed in 6 different pairs of chromosomes. Three clones were respectively assigned to a pair of metacentric chromosomes, a pair of submetacentric chromosomes and a pair of telocentric chromosomes and the remaining 3 clones showed their loci on three different pairs of subtelocentric chromosomes by co-hybridization. In summary, totally 8 pairs of chromosomes of the Yesso scallop were identified by 6 fosmid clones and two rDNA probes. Furthermore, 6 tandem repeats of 5 clones were sequenced and could be developed as chromosome specific markers for the Yesso scallop. The successful localization of fosmid clones will undoubtedly facilitate the integration of linkage groups with cytogenetic map and genomic research for the Yesso scallop

    Cloning, expression pattern and promoter functional analysis of cyp19a1a gene in miiuy croaker

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    Gonadal-specific aromatase encoded by cyp19a1a is the important enzyme controlling estrogen biosynthesis in teleosts. In the present study, the cDNA sequence of cyp19a1a was cloned and characterized from miiuy croaker Miichthys miiuy. The cDNA encoded a protein of 519 amino acids with five structural regions. Higher identities of amino acid sequences and conserved structural regions were found between Mmcyp19a1a and other cyp19a1a genes. In addition, Mmcyp19a1a was clustered together with other seawater fishes. Immunohistochemical analysis revealed that Mmcyp19a1a was localized exclusively in the cytoplasmic of thecal and granulosa cells surrounding the oocytes. Both the protein and mRNA levels of Mmcyp19a1a were increased significantly at the stage III follicles (mid-vitellogenic) and then decreased along with vitellogenesis. Interestingly, strong immunoreactive signals were also detected in the supporting cells of connective tissues during ovarian development. A 1777 bp promoter fragment of Mmcyp19a1a was also isolated, and functional analysis using an EGFP reporter fusion in zebrafish larvae presented positive signals in the above of yolk sac, where is the region of pronephros and germ plasm occur. The Mmcyp19a1a:EGFP expression pattern was generally consistent with the endogenous cyp19a1a genesis. These results indicate that the Mmcyp19a1a gene plays an important role during vitellogenesis and oocyte maturation. The constructor of Mmcyp19a1a:EGFP may provide a useful tool for genetic analysis of gonad development in teleost.</p
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