• Title/Summary/Keyword: blast analysis

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An experimental study for developing of silencer to be adapted large gun (대구경 화포용 소음기 개발을 위한 실험적 연구)

  • Lee, Hae suk;Park, Sung ho;Kim, Sang min;Kang, Tae yeop;Kim, Heung soo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.04a
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    • pp.558-563
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    • 2014
  • To reduce the transmission of large gun-generated noise from the firing test range to the community, we have tested a silencer to be used with howitzer(155mm KM114A2) after simulation. Numerical analysis was conducted by using a commercial CFD code, FLUENT. To analyze complex blast flow fields, the Spalart-Allmaras model was applied under 2 dimensional and axisymmetric conditions. Firing tests were also performed with the KM114A2 howitzer while the silencer was installed. This paper describes a result of comparison between results of computer analysis and test outcomes which were gotten by firing 155mm projectiles at the testing range. This paper will also be informative to the muffler design which will be adapted to 155mm large gun in the future.

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Analysis of RC beams subjected to shock loading using a modified fibre element formulation

  • Valipour, Hamid R.;Huynh, Luan;Foster, Stephen J.
    • Computers and Concrete
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    • v.6 no.5
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    • pp.377-390
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    • 2009
  • In this paper an improved one-dimensional frame element for modelling of reinforced concrete beams and columns subjected to impact is presented. The model is developed in the framework of a flexibility fibre element formulation that ignores the shear effect at material level. However, a simple shear cap is introduced at section level to take account of possible shear failure. The effect of strain rate at the fibre level is taken into account by using the dynamic increase factor (DIF) concept for steel and concrete. The capability of the formulation for estimating the element response history is demonstrated by some numerical examples and it is shown that the developed 1D element has the potential to be used for dynamic analysis of large framed structures subjected to impact of air blast and rigid objects.

Finite Element Analysis for Iron-Making Furnace (제철용 고로의 유한요소해석)

  • 이만승;백점기;이제명
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.10a
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    • pp.245-253
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    • 2004
  • There has been recent demand for extending the life of age-degraded structures and equipment by such techniques as diagnosis, maintenance, safety assessment, and estimating residual life on iron-making plants and hydraulic, thermal, and nuclear power plants. These techniques take into account comprehensive scenarios that may cause malfunction and structural damage and allow an assessment of risk based on the likely scenarios. In particular the safety assessment and residual life estimation of age-degraded ships and equipment facilities require consideration of various factors such as mechanical and thermal stresses, corrosion, hardness, load variation due to changes of operating condition, crack generation and strength reduction of material by fatigue. In this study, a detail thermal stress analysis, one of useful techniques of safety assessment and maintenance, is performed on a blast furnace by using general FEM code (MSC/NASTRAN).

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Construction of a Genetic Information Database for Analysis of Oncolytic Viruses

  • Cho, Myeongji;Son, Hyeon Seok;Kim, Hayeon
    • International journal of advanced smart convergence
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    • v.9 no.1
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    • pp.90-97
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    • 2020
  • Oncolytic viruses are characterized by their ability to selectively kill cancer cells, and thus they have potential for application as novel anticancer agents. Despite an increase in the number of studies on methodologies involving oncolytic viruses, bioinformatic studies generating useful data are lacking. We constructed a database for oncolytic virus research (the oncolytic virus database, OVDB) by integrating scattered genetic information on oncolytic viruses and proposed a systematic means of using the biological data in the database. Our database provides data on 14 oncolytic viral strains and other types of viruses for comparative analysis. We constructed the OVDB using the basic local alignment search tool, and therefore can provides genetic information on highly homologous oncolytic viruses. This study contributes to facilitate systematic bioinformatics research, providing valuable data for development of oncolytic virus-based anticancer therapies.

Newly developed MSAP analysis reveals the different polymorphism patterns in transgenic tobacco plants with the dsRNA MET1 gene

  • Oh, Yun Jung;Chung, Hee;Yu, Jae Gyeong;Park, Young Doo
    • Plant Biotechnology Reports
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    • v.3 no.2
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    • pp.139-145
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    • 2009
  • DNA methylation is known to play an important role in the regulation of gene expression in eukaryotes. In this study, we isolated NtMET1 from Nicotiana tabacum cv. Havana (SR1) and obtain transgenic plants that reduced MET1 expression level with the double-strand RNA (dsRNA) MET1 gene. Transgenic tobacco plants showed dwarf and abnormal flower development when compared with the wild type. Using methylation-sensitive amplified polymorphism (MSAP) analysis, the patterns of cytosine methylation in transformed plants and the wild type were compared. MseI/HpaII selection primers showed an interesting polymorphism, and 153 DNA bands of interest were detected. Among these, 30 selective fragments were sequenced and analyzed with a BLAST search by successful MSAP modifications. The homology search showed that the transposons and tandem repeated sequences were related to the phenotypes. These results suggested that the decreased degree of methylation by dsRNA strategy caused abnormal growth and development in N. tabacum.

A method and analysis of human-error management of a semiconductor industry (반도체산업에서의 인적오류제어방법 및 연구)

  • Yoon Yong-Gu;Park Peom
    • Journal of the Korea Safety Management & Science
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    • v.8 no.1
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    • pp.17-26
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    • 2006
  • Basis frame-work's base in a semiconductor industry have gas, chemical, electricity and various facilities in bring to it. That it is a foundation by fire, power failure, blast, spill of toxicant huge by large size accident human and physical loss and damage because it can bring this efficient, connect with each kind mechanical, physical thing to prevent usefully need that control finding achievement factor of human factor of human action. Large size accident in a semiconductor industry to machine and human and it is involved that present, in system by safety interlock defect of machine is conclusion for error of behaviour. What is not construing in this study, do safety in a semiconductor industry to do improvement. Control human error analyzes in human control with and considers mechanical element and several elements. Also, apply achievement factor using O'conner Model by control method of human error. In analyze by failure mode effect using actuality example.

Analysis of Nanostructural Deformation Behavior of Cement Clinker Substituting High-volume Fly ash by Pair Distribution Function (원자짝 분포 함수를 이용한 플라이애시를 대량 치환한 시멘트 클링커의 나노 구조 변형 거동 해석)

  • Jee, Hyeon-Seok;Park, Jae-Yeon;Bae, Sung-Chul
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2019.05a
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    • pp.112-113
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    • 2019
  • Recently, supplementary cementitious materials such as blast-furnace slag, fly ash and silica fume have been widely used as substitutes for cementitious materials. In this study, the deformation behavior of compressive loading of C3S paste with 50% fly ash was analyzed by X-ray scattering data and pair distribution function analysis. The obtained results were compared with 131-day-old pure C3S paste. The Ca(OH)2 of the C3S-FA paste showed almost complete elastic behavior, consistent with the deformation behavior of the r-range of 20 to 40, and the C-S-H phase contributed to the range of PDF r-range of less than 20. In addition, C-S-H of C3S-FA showed greater deformation resistance than C3S paste.

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Dynamic Influence of Tunnel Blasting on Adjacent Structures for Various RMR Values (발파에 의한 터널 굴착시 RMR값에 따른 인접구조물의 동적 영향)

  • 허재록;황의석;이봉열;김학문
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.657-664
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    • 2002
  • This study presents the influence of blasting-induced vibration on the adjacent structures in rocks of various RMR values. 3D finite element analysis was performed to simulate the behaviour of tunnel and adjacent structures during rock excavation. The blast loadings were evaluated from the blasting pressure which is depending on the type and amount of explosive charges. Influencing factors for the stability of adjacent structures and ground conditions were reviewed in terms of structural dimensions and RMR values. The stiffness and load of adjacent structures are modeled in the numerical analysis to Investigate blasting effects of the size of adjacent structures. The vibration velocity and maximum particle velocity was increase sharply when the RMR value changed from 30 to 50. The effect of particle velocity was minimized at the width of structure become 2 times of tunnel diameter.

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Pore Structure and Heat of Microhydration Analysis of Blast Furnace Slag Containing Alkaline Activator (알칼리 자극제 혼입 고로슬래그 미분말의 공극구조 및 미소수화열 분석)

  • Park, Ji-Woong;Park, Hee-Gon;Kim, Woo-Jae;Lee, Gun-Cheol
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2017.11a
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    • pp.20-21
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    • 2017
  • In this study, fundamental properties by pore structure and heat of microhydration test were determined. As a result of pore structure analysis, BS(AA) specimen showed showed the maximum peak value of significantly lower incremental intrusion than the maximum peak value of incremental intrusion at smaller pore size than that of BS. As a result of heat of microhydration test, the maximum heating value was in the order of OPC > BS > BS(AA), and initial drying shrinkage and compressive strength of BS(AA) were expected to be improved.

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Phylogenetic and Morphological Characterization of Cladosporium perangustum Associated with Flyspeck on Shine Muscat Grapes in South Korea

  • Hassan, Oliul;Lim, Yang-Sook;Chang, Taehyun
    • Mycobiology
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    • v.49 no.2
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    • pp.183-187
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    • 2021
  • The Shine Muscat is a table grape, popular in South Korea for its unique mango-flavor taste. Flyspeck is a disease that is characterized by small, black, and circular specks on the grape cuticle was first observed in several commercial orchards in Sangju, South Korea, in August 2019. Here we identified the causal agent of flyspeck based on an advanced diagnosis approach, comprised of both morphological and molecular analyses. Morphological characteristics of the cultures isolated from grape flyspeck were identical to the fungus Cladosporium perangustum. The concatenated sequences of ITS, ACT, and EF1-α were used for molecular phylogenetic analysis, BLAST searches along with Bayesian inference-based phylogeny, confirmed that the causal agent of grape flyspeck is C. perangustum. The cultured fungal isolates also produced flyspeck symptoms on healthy fruits in pathogenicity tests. To the best of my knowledge, this is the first documented evidence of any Cladosporium sp. producing flyspeck symptoms on any plant.