• Title/Summary/Keyword: A321

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A new species of the genus Monoblastus Hartig (Hymenoptera: Ichneumonidae: Tryphoninae) with a key to species from South Korea

  • Jin-Kyung Choi
    • Journal of Species Research
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    • v.12 no.4
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    • pp.321-325
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    • 2023
  • A new species, Monoblastus forsythia sp. nov. is described from South Korea. All specimens of this new species were collected on Forsythia koreana (Nakai). A taxonomic study of South Korean Monoblastus was initiated by Uchida in 1930, and until now four species have been recorded from South Korea. The genus Monoblastus is a Holarctic genus with 31 described species, 14 species are Nearctic, seven are Western Palaearctic region, and nine species occur in Eastern Palaearctic region. In the study, I provide description and photos of both sexes of this new species. Also, modified key to species of the South Korean Monoblastus is provided.

A POSTERIORI L(L2)-ERROR ESTIMATES OF SEMIDISCRETE MIXED FINITE ELEMENT METHODS FOR HYPERBOLIC OPTIMAL CONTROL PROBLEMS

  • Hou, Tianliang
    • Bulletin of the Korean Mathematical Society
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    • v.50 no.1
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    • pp.321-341
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    • 2013
  • In this paper, we discuss the a posteriori error estimates of the semidiscrete mixed finite element methods for quadratic optimal control problems governed by linear hyperbolic equations. The state and the co-state are discretized by the order $k$ Raviart-Thomas mixed finite element spaces and the control is approximated by piecewise polynomials of order $k(k{\geq}0)$. Using mixed elliptic reconstruction method, a posterior $L^{\infty}(L^2)$-error estimates for both the state and the control approximation are derived. Such estimates, which are apparently not available in the literature, are an important step towards developing reliable adaptive mixed finite element approximation schemes for the control problem.

Synthesis and Crystal Structures of Zn(II)- and Mn(II)- Diphenyldicarboxylate Complexes with N-Donor Ligand

  • Koo, Bon Kweon
    • Journal of the Korean Chemical Society
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    • v.60 no.5
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    • pp.321-326
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    • 2016
  • Two new polymeric complexes, [Zn(dpa)(pyz)0.5]n (1; dpa = diphenate and pyz = pyrazine) and [Mn3(bpdc)3(py)4]n (2; bpdc = biphenyl-4,4'-dicarboxylate and py = pyridine) were successfully isolated by the hydro- and solvo-thermal technique, respectively. The complexes were characterized by elemental and thermal analysis, vibrational IR spectroscopy, and by single crystal x-ray structure determination. For 2, magnetic property was also investigated. Complex 1 is a two-dimensional layer structure consisting of a paddle-wheel building unit of Zn-dpa chains bridged by pyrazine. While, complex 2 consists of linear trimeric Mn3 cluster as building unit to form 3D network. In the complexes, dpa2− (1) and bpdc2−(2) ligands show a typical bis-monodendate bridging and two kinds of bridging modes; a typical bridging and chelating/bridging mode, respectively.

The effect of internal axial forces of a cantilever beam with a lumped mass at its free end

  • Zhang, Jinfu
    • Coupled systems mechanics
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    • v.7 no.3
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    • pp.321-331
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    • 2018
  • When a cantilever beam with a lumped mass at its free end undergoes free transverse vibration, internal axial forces are produced in the beam. Such internal axial forces have an effect on free transverse vibration of the beam. This effect is studied in this paper. The equations of motion for the beam in terms of the generalized coordinates including the effect are derived. The method for determining free transverse vibration of the beam including the effect is presented. In numerical simulations, the results of free transverse vibration of the free end of the beam including and not including the effect are obtained. Based on comparison between the results obtained, the conclusions concerning the effect are given.

Dactylospora glaucomarioides (Ascomycetes, Dactylosporaceae): A Lichenicolous Fungus New to South Korea

  • Joshi, Yogesh;Knudsen, Kerry;Wang, Xin Yu;Hur, Jae-Seoun
    • Mycobiology
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    • v.38 no.4
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    • pp.321-322
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    • 2010
  • The lichenicolous fungi flora of South Korea is poorly known. During recent field trips to various parts of South Korea and after an extensive examination of herbarium lichen specimens, we encountered a lichenicolous fungi growing over a thallus of the lichen Ochrolechia yasudae Vain., characterized by small black apothecia with mostly three-septate brown ascospores. It was identified as Dactylospora glaucomarioides. This is the first report of this lichenicolous fungus from South Korea. A taxonomic description and comments are presented.

Transformation Optics Methodology for Changing the Appearance of an Object

  • Li, Yanxiu;Kong, Fanmin;Li, Kang
    • Journal of the Optical Society of Korea
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    • v.20 no.2
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    • pp.321-324
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    • 2016
  • Transformation optics methodology provides a new pathway for designing novel devices. It is based on changing a material’s permittivity and permeability. A design for changing the appearance of an object by transformation optics methodology is proposed here. Through a certain transformation, the relations of the metric spaces and the calculation of the material parameters are derived, and the aim of changing the apparent size of an object can be realized. Full wave simulations are performed to validate the proposed device’s performance. It is possible to think that the methodology will improve the flexibility of designing interesting applications in microwave and optical regimes.

Inelastic two-degree-of-freedom model for roof frame under airblast loading

  • Park, Jong Yil;Krauthammer, Theodor
    • Structural Engineering and Mechanics
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    • v.32 no.2
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    • pp.321-335
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    • 2009
  • When a roof frame is subjected to the airblast loading, the conventional way to analyze the damage of the frame or design the frame is to use single degree of freedom (SDOF) model. Although a roof frame consists of beams and girders, a typical SDOF analysis can be conducted only separately for each component. Thus, the rigid body motion of beams by deflections of supporting girders can not be easily considered. Neglecting the beam-girder interaction in the SDOF analysis may cause serious inaccuracies in the response values in both Pressure-Impulse curve (P-I) and Charge Weight-Standoff Diagrams (CWSD). In this paper, an inelastic two degrees of freedom (TDOF) model is developed, based on force equilibrium equations, to consider beam-girder interaction, and to assess if the modified SDOF analysis can be a reasonable design approach.

Numerical Analysis of Cavitating Flow around Two-dimensional Wedge-shaped Submerged Bodies under the Wall Effect (벽면효과를 받는 2차원 쐐기형 몰수체의 공동 유동에 대한 수치해석)

  • Kim, Ji-Hye;Ahn, Byoung-Kwon
    • Journal of the Society of Naval Architects of Korea
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    • v.54 no.4
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    • pp.321-328
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    • 2017
  • In practice, cavitation phenomena occur in unbounded flows. However, the wall effect is unavoidable during experiments at a closed section such as a cavitation tunnel. Especially, supercavity generated behind a cavitator is relatively large and thick, so that geometric and dynamic characteristics of the cavity are affected by the tunnel wall. In order to apply experimental results into the unbounded flow field, physical correlations are necessary. In this paper, we proposed an image method based on a potential flow to simulate the wall effect. Considering two-dimensional wedge-shaped bodies, configurations and drag characteristics of the cavity were examined according to the distance ratio to the wall surface. The results were compared and verified with existing theoretical and experimental results.

Accuracy Evaluation of Regional Wall Motion Abnormality in Echocardiography and Cardiac Enzymes in the Diagnosis of Ischemic Heart Disease (허혈성심장질환 진단에서 심장초음파의 국소벽운동이상과 심장효소의 정확성 평가)

  • Kim, Hee-Young;Ji, Tae-Jeong
    • Journal of radiological science and technology
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    • v.45 no.4
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    • pp.321-330
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    • 2022
  • Echocardiography and cardiac enzymes test are the tests to assess ischemic heart disease. The purpose of this study was to verify the accuracy by comparing and analyzing two tests for the diagnosis of ischemic heart disease. A retrospective study was conducted on 393 study subjects who underwent echocardiography and cardiac enzymes test. As a result of the study, regional wall motion abnormality (RWMA) increased as the age of the study subjects increased. As a result of ROC analysis, RWMA showed a larger area under the curve (AUC) than cardiac enzymes. RWMA showed the highest accuracy with 81.1% of all cardiac enzymes. Among cardiac enzymes, cTnI showed the highest accuracy. Thus, It was confirmed that RWMA of echocardiography is more accurate than cardiac enzyme is in diagnosing ischemic heart disease.

GROUP S3 MEAN CORDIAL LABELING FOR STAR RELATED GRAPHS

  • A. LOURDUSAMY;E. VERONISHA
    • Journal of applied mathematics & informatics
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    • v.41 no.2
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    • pp.321-330
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    • 2023
  • Let G = (V, E) be a graph. Consider the group S3. Let g : V (G) → S3 be a function. For each edge xy assign the label 1 if ${\lceil}{\frac{o(g(x))+o(g(y))}{2}}{\rceil}$ is odd or 0 otherwise. g is a group S3 mean cordial labeling if |vg(i) - vg(j)| ≤ 1 and |eg(0) - eg(1)| ≤ 1, where vg(i) and eg(y)denote the number of vertices labeled with an element i and number of edges labeled with y (y = 0, 1). The graph G with group S3 mean cordial labeling is called group S3 mean cordial graph. In this paper, we discuss group S3 mean cordial labeling for star related graphs.