• Title/Summary/Keyword: Modular Frame

Search Result 56, Processing Time 0.027 seconds

Evaluation of vibroacoustic responses of laminated composite sandwich structure using higher-order finite-boundary element model

  • Sharma, Nitin;Mahapatra, Trupti R.;Panda, Subrata K.;Mehar, Kulmani
    • Steel and Composite Structures
    • /
    • v.28 no.5
    • /
    • pp.629-639
    • /
    • 2018
  • In this paper, the vibroacoustic responses of baffled laminated composite sandwich flat panel structure under the influence of harmonic excitation are studied numerically using a novel higher-order coupled finite-boundary element model. A numerical scheme for the vibrating plate has been developed in the frame work of the higher-order mid-plane kinematics and the eigen frequencies are obtained by employing suitable finite element steps. The acoustic responses are then computed by solving the Helmholtz wave equation using boundary element method coupled with the structural finite elements. The proposed scheme has been implemented via an own MATLAB base code to compute the desired responses. The validity of the present model is established from the conformance of the current natural frequencies and the radiated sound power with the available benchmark solutions. The model is further utilized to scrutinize the influence of core-to-face thickness ratio, modular ratio, lamination scheme and the support condition on the sound radiation characteristics of the vibrating sandwich flats panel. It can be concluded that the present scheme is not only accurate but also efficient and simple in providing solutions of the coupled vibroacoustic response of laminated composite sandwich plates.

A Study on the Buckling Characteristics of Steel Pipe Scaffold (강관비계의 좌굴특성에 관한 연구)

  • Paik, Shin-Won;Song, In-Yong
    • Journal of the Korean Society of Safety
    • /
    • v.25 no.1
    • /
    • pp.57-61
    • /
    • 2010
  • Formwork is a temporary structure that supports its weight and that of fresh concrete as well as construction live loads. Scaffoling is a temporary frame used to support people and material in the construction or repair of buildings and other large structures. It is usually a modular system of metal pipes, although it can be made out of other materials. Bamboo is still used in some Asian countries like China. The purpose of a working scaffold is to provide a safe place of work with safe access suitable for the work being done. In construction site, steel pipes are usually used as scaffolds. In this study, scaffolding systems which is changed according to sleeper and joist space were measured by buckling test. Buckling load of respective scaffolding system was analyzed by structural analysis program(MIDAS). Buckling load of scaffold with/without wall connection and footboard was got by test and structural analysis. According to these results,we know that scaffolding system of case 3 is suitable. Buckling load of scaffold with wall connection is higher than without wall connection. So wall connection is important in scaffoling systems. Footboard in the scaffolding systems is not effective against promotion of buckling load. Finally, the present study results will be used to design scaffolding systems safely in the construction sites.

Isolation of N-Acetylmuramoyl-L-Alanine Amidase Gene (amiB) from Vibrio anguillarum and the Effect of amiB Gene Deletion on Stress Responses

  • Ahn Sun-Hee;Kim Dong-Gyun;Jeong Seung-Ha;Hong Gyeong-Eun;Kong In-Soo
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.9
    • /
    • pp.1416-1421
    • /
    • 2006
  • We identified a gene encoding the N-acetylmuramoyl L-alanine amidase (amiB) of Vibrio anguillarum, which catalyzes the degradation of peptidoglycan in bacteria. The entire open reading frame (ORF) of the amiB gene was composed of 1,722 nucleotides and 573 amino acids. The deduced amino acid sequence of AmiB showed a modular structure with two main domains; an N-terminal region exhibiting an Ami domain and three highly conserved, continuously repeating LysM domains in the C-terminal portion. An amiB mutant was constructed by homologous recombination to study the biochemical function of the AmiB protein in V. anguillarum. Transmission electron microscopy (TEM) revealed morphological differences, and that the mutant strain formed trimeric and tetrameric unseparated cells, suggesting that this enzyme is involved in the separation of daughter cells after cell division. Furthermore, inactivation of the amiB gene resulted in a marked increase of sensitivity to oxidative stress and organic acids.

Genomic Analyses of Toll-like Receptor 4 and 7 Exons of Bos indicus from Temperate Sub-himalayan Region of India

  • Malik, Y.P.S.;Chakravarti, S.;Sharma, K.;Vaid, N.;Rajak, K.K.;Balamurugan, V.;Biswas, S.K.;Mondal, B.;Kataria, R.S.;Singh, R.K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.24 no.7
    • /
    • pp.1019-1025
    • /
    • 2011
  • Toll-like receptors (TLRs) play an important role in the recognition of invading pathogens and the modulation of innate immune responses in mammals. The TLR4 and TLR7 are well known to recognize the bacterial lipopolysaccharide (LPS) and single stranded (ssRNA) ligands, respectively and play important role in host defense against Gram-negative bacteria and ssRNA viruses. In the present study, coding exon fragments of these two TLRs were identified, cloned, sequenced and analyzed in terms of insertion-deletion polymorphism, within bovine TLRs 4 and 7, thereby facilitating future TLR signaling and association studies relevant to bovine innate immunity. Comparative sequence analysis of TLR 4 exons revealed that this gene is more variable, particularly the coding frame (E3P1), while other parts showed percent identity of 95.7% to 100% at nucleotide and amino acid level, respectivley with other Bos indicus and Bos taurus breeds from different parts of the world. In comparison to TLR4, sequence analysis of TLR7 showed more conservation among different B. indicus and B. taurus breeds, except single point mutation at 324 nucleotide position (AAA to AAM) altering a single amino acid at 108 position (K to X). Percent identity of TLR7 sequences (all 3 exons) was between 99.2% to 100% at nucleotide and amino acid level, when compared with available sequence database of B. indicus and B. taurus. Simple Modular Architecture Research Tool (SMART) analysis showed variations in the exon fragments located in the Leucine Rich Repeat (LRR) region, which is responsible for binding with the microbial associated molecular patterns and further, downstream signaling to initiate anti-microbial response. Considering importance of TLR polymorphism in terms of innate immunity, further research is warranted.

Cloning a Mannanase 26AT Gene from Paenibacillus woosongensis and Characterization of the Gene Product (Paenibacillus woosongensis으로부터 Mannanase 26AT 유전자의 클로닝과 유전자 산물의 분석)

  • Yoon, Ki-Hong
    • Journal of Life Science
    • /
    • v.27 no.9
    • /
    • pp.1003-1010
    • /
    • 2017
  • An open reading frame coding for mannanase predicted from the partial genomic sequence of Paenibacillus woosongensis was cloned into Escherichia coli by polymerase chain reaction amplification, and completely sequenced. This mannanase gene, designated man26AT, consisted of 3,162 nucleotides encoding a polypeptide of 1,053 amino acid residues. Based on the deduced amino acid sequence, Man26AT was identified as a modular enzyme, which included a catalytic domain belonging to the glycosyl hydrolase family 26 and two carbohydrate-binding modules, CBM27 and CBM11. The amino acid sequence of Man26AT was homologous to that of several putative mannanases, with identity of 81% for P. ihumii and identity of less than 57% for other strains of Paenibacillus. A cell-free extract of recombinant E. coli carrying the man26AT gene showed maximal mannanase activity at $55^{\circ}C$ and pH 5.5. The enzyme retained above 80% of maximal activity after preincubation for 1 h at $50^{\circ}C$. Man26AT was comparably active on locust bean gum (LBG), galactomanan, and kojac glucomannan, whereas it did not exhibit activity on carboxymethylcellulose, xylan, or para-nitrophenyl-${\beta}$-mannopyranoside. The common end products liberated from mannooligosaccharides, including mannotriose, mannotetraose, mannopentaose, and mannohexaose, or LBG by Man26AT were mannose, mannobiose, and mannotriose. Mannooligosacchrides larger than mannotriose were found in enzymatic hydrolyzates of LBG and guar gum, respectively. However, Man26AT was unable to hydrolyze mannobiose. Man26AT was intracellularly degraded into at least three active proteins with different molecular masses by zymogram.

An Analysis of Similarity Measures for Area-based Multi-Image Matching (다중영상 영역기반 영상정합을 위한 유사성 측정방법 분석)

  • Noh, Myoung-Jong;Kim, Jung-Sub;Cho, Woo-Sug
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.30 no.2
    • /
    • pp.143-152
    • /
    • 2012
  • It is well-known that image matching is necessary for automatic generation of 3D data such as digital surface data from aerial images. Recently developed aerial digital cameras allow to capture multi-strip images with higher overlaps and less occluded areas than conventional analogue cameras and that much of researches on multi-image matching have been performed, particularly effective methods of measuring a similarity among multi-images using point features as well as linear features. This research aims to investigate similarity measuring methods such as SSD and SNCC incorporated into a area based multi-image matching method based on vertical line locus. In doing this, different similarity measuring entities such as grey value, grey value gradient, and average of grey value and its gradient are implemented and analyzed. Further, both dynamic and pre-fixed adaptive-window size are tested and analyzed in their behaviors in measuring similarity among multi-images. The aerial images used in the experiments were taken by a DMC aerial frame camera in three strips. The over-lap and side-lap are about 80% and 60%, respectively. In the experiment, it was found that the SNCC as similarity measuring method, the average of grey value and its gradient as similarity measuring entity, and dynamic adaptive-window size can be best fit to measuring area-based similarity in area based multi-image matching method based on vertical line locus.