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On the Basis Number of the Semi-Strong Product of Bipartite Graphs with Cycles

  • Jaradat, M.M.M.;Alzoubi, Maref Y.
    • Kyungpook Mathematical Journal
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    • v.45 no.1
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    • pp.45-53
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    • 2005
  • A basis of the cycle space C (G) is d-fold if each edge occurs in at most d cycles of C(G). The basis number, b(G), of a graph G is defined to be the least integer d such that G has a d-fold basis for its cycle space. MacLane proved that a graph G is planar if and only if $b(G)\;{\leq}\;2$. Schmeichel showed that for $n\;{\geq}\;5,\;b(K_{n}\;{\bullet}\;P_{2})\;{\leq}\;1\;+\;b(K_n)$. Ali proved that for n, $m\;{\geq}\;5,\;b(K_n\;{\bullet}\;K_m)\;{\leq}\;3\;+\;b(K_n)\;+\;b(K_m)$. In this paper, we give an upper bound for the basis number of the semi-strong product of a bipartite graph with a cycle.

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Development of Organic-Inorganic Hybrid Dielectric for Organic Thin Film Transistors

  • Jeong, Sun-Ho;Kim, Dong-Jo;Lee, Sul;Park, Bong-Kyun;Moon, Joo-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1115-1118
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    • 2006
  • Using a thermally-crosslinkable organosiloxane-based organic-inorganic hybrid material, solution processable gate dielectric layer for organic thin-film transistors (OTFTs) have been fabricated. The hybrid dielectrics are synthesized by the sol-gel process, followed by the heat-treatment at $190{\bullet}\;.{\bullet}$ To investigate the electrical property of hybrid dielectric, leakage current behavior and capacitance were measured. To fabricate coplanar-type OTFTs, Au/Cr electrode was deposited onto the heavily doped silicon substrate with the organic-inorganic hybrid dielectric layer and then ${\alpha},{\omega}-dihexylquaterthiophene$ was drop-cast between source and drain electrical performance of the fabricated transistor.

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Loss of HCN from the Pyrazine Molecular Ion: A Theoretical Study

  • Jung, Sun-Hwa;Yim, Min-Kyoung;Choe, Joong-Chul
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2301-2305
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    • 2011
  • The potential energy surface (PES) for the loss of HCN or HNC from the pyrazine molecular ion was determined based on quantum chemical calculations using the G3//B3LYP method. Four possible dissociation pathways to form four $C_3H_3N^{+{{\bullet}}$ isomers were examined. A Rice-Ramsperger-Kassel-Marcus quasi-equilibrium theory model calculation was performed to predict the dissociation rate constant and the product branching ratio on the basis of the obtained PES. The resultant rate constant for the HCN loss agreed with the previous experimental result. The kinetic analysis predicted that the formation of $CH=CHN{\equiv}CH^{+{\bullet}}+HCN$ was predominant, which occurred by three consecutive steps, a C-C bond cleavage to form a linear intermediate, a rearrangement to form an H-bridged intermediate, and elimination of HCN.

The southeastern region of the Vela SNR

  • Kim, Il-Joong;Seon, Kwang-Il;Min, Kyoung-Wook
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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    • pp.69.2-69.2
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    • 2010
  • We investigate the southeastern region of the Vela supernova remnant (SNR) in the multi-wavelength domains. This region is quite interesting because it includes the bullet feature D/D´ and another SNR (the Vela Jr.). The C IV $\lambda\lambda1548$, 1551 emission-line morphologies obtained from the FIMS/SPEAR data show that there are several local peaks of C IV on the bullet D/D´ and the Vela Jr. SNR. This may provide clues to direct interaction between both SNRs. Also, we found that the southeastern side of the Vela is in direct contact with an H-alpha ring feature whose central source seems to be a B-type star, HD 76161. The C IV emission peaks along this contact boundary. We investigate this interacting region in detail.

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Causes of the Fire at an Indoor Shooting Range in Busan

  • Park, Woe-Chul;Lee, Nae-Woo;Jeong, Lee-Gyu
    • International Journal of Safety
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    • v.9 no.1
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    • pp.1-5
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    • 2010
  • On-site examinations and fire simulation were carried out to speculate on causes of the fire at an indoor shooting range in Busan. An experiment on the ignitability of unburned gunpowder was also conducted. Cigarette was the most likely source of ignition for the fire, while impact of a stray bullet failed to ignite the unburned gunpowder. The explosion in the shooting area was presumed to be caused by violent combustion of the polyurethane foam and unburned gunpowder accumulated on it. Fire safety measures include prohibit of use of profile polyurethane foam, complete clean-up of unburned gunpowder, and removal of steel components from the bullet trap.

Stack Effect Guidelines for Tall, Mega Tall and Super Tall Buildings

  • Simmonds, Peter;Zhu, Rui
    • International Journal of High-Rise Buildings
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    • v.2 no.4
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    • pp.323-330
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    • 2013
  • The ASHRAE Technical Committee for Tall Buildings, TC 9.12, has defined a tall building as one whose height is greater than 300 feet (91m). Since the publication of the HVAC Design Guide for Tall Commercial Buildings in 2004, there were only about 300 buildings taller than 200 meters; this number has risen to 600 in 2010 and the prediction 765 buildings taller than 200 meters in 2012. There has also been an introduction of two new classes of tall buildings: ${\bullet}$ Mega tall, which are buildings taller than 300 m, and ${\bullet}$ Super tall, which are buildings taller than 600 m. The effect of ambient air temperature over the height of buildings, especially Mega tall and Super tall buildings. The ambient climatic conditions vary with altitude and these changes in ambient conditions can seriously affect load calculations and performance of super and mega tall buildings. This paper presents revised calculations for stack effect for Tall, Mega Tall and Super tall Buildings.

Development of Waterproof Acoustic Sensor for Shockwave Measurement (탄환 충격파 측정용 방수 음향센서 개발)

  • Hur, Shin;Lee, Duck-Gyu
    • Journal of Sensor Science and Technology
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    • v.28 no.5
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    • pp.318-322
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    • 2019
  • In shooting training, an impact point identification system that uses the impact wave of the bullet to check the impact point in the target plate has been recently used. Acoustic sensors used in these systems must be able to detect shock waves of high sound pressure levels and be both waterproof and dustproof for rainy weather and dusty environments, respectively. In this study, membranes with excellent waterproof, dustproof, and sound transmitting characteristics were selected through a characteristics test; a protection cap was installed to install the selected materials. After coupling the produced protection cap to the acoustic sensor housing, the sensitivity and phase characteristics of the acoustic sensor were checked. Through the waterproof and dustproof test, the performances of its sensitivity and phase characteristics were confirmed. Finally, the normal shockwave of a 5.56 mm diameter bullet was measured using a shockwave detection signal collecting plate equipped with a prototype of the acoustic sensor at a 100 m firing range.

NONLINEAR MIXED *-JORDAN TYPE n-DERIVATIONS ON *-ALGEBRAS

  • Raof Ahmad Bhat;Abbas Hussain Shikeh;Mohammad Aslam Siddeeque
    • Communications of the Korean Mathematical Society
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    • v.39 no.2
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    • pp.331-343
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    • 2024
  • Let ℜ be a *-algebra with unity I and a nontrivial projection P1. In this paper, we show that under certain restrictions if a map ψ : ℜ → ℜ satisfies $$\Psi(S_1{\diamond}S_2{\cdot}{\cdot}{\cdot}{\diamond}S_{n-1}{\bullet}S_n)=\sum_{k=1}^nS_1{\diamond}S_2{\diamond}{\cdot}{\cdot}{\cdot}{\diamond}S_{k-1}{\diamond}{\Psi}(S_k){\diamond}S_{k+1}{\diamond}{\cdot}{\cdot}{\cdot}{\diamond}S_{n-1}{\bullet}S_n$$ for all Sn-2, Sn-1, Sn ∈ ℜ and Si = I for all i ∈ {1, 2, . . . , n - 3}, where n ≥ 3, then ψ is an additive *-derivation.