• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.248-248
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• 2012

Synthesis graphene on Cu substrate by plasma-enhanced chemical vapor deposition (PE-CVD) is investigated and its quality's affection factors are discussed in this work. Compared with the graphene synthesized at high temperature in chemical vapor deposition (CVD), the low-temperature graphene film by PE-CVD has relatively low quality with many defects. However, the advantage of low-temperature is also obvious that low melting point materials will be available to synthesize graphene as substrate. In this study, the temperature will be kept constant in $400^{\circ}C$ and the graphene was grown in plasma environment with changing the plasma power, the flow rate of precursors, and the distance between plasma generator coil and substrates. Then, we investigate the effect of temperature and the influence of process variables to graphene film's quality and characterize the film properties with Raman spectroscopy and sheet resistance and optical emission spectroscopy.

• Structural Engineering and Mechanics
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• v.14 no.3
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• pp.245-262
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• 2002

The free vibration analysis of stiffened laminated composite plates has been performed using the layered (zigzag) finite element method based on the first order shear deformation theory. The layers of the laminated plate is modeled using nine-node isoparametric degenerated flat shell element. The stiffeners are modeled as three-node isoparametric beam elements based on Timoshenko beam theory. Bilinear in-plane displacement constraints are used to maintain the inter-layer continuity. A special lumping technique is used in deriving the lumped mass matrices. The natural frequencies are extracted using the subspace iteration method. Numerical results are presented for unstiffened laminated plates, stiffened isotropic plates, stiffened symmetric angle-ply laminates, stiffened skew-symmetric angle-ply laminates and stiffened skew-symmetric cross-ply laminates. The effects of fiber orientations (ply angles), number of layers, stiffener depths and degrees of orthotropy are examined.

• Wind and Structures
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• v.9 no.4
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• pp.331-344
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• 2006

The cable-stayed-suspension hybrid bridge is a cooperative system developed from the traditional cable-stayed and suspension bridges, and takes some advantages of the two bridge systems. It is also becoming a competitive design alternative for some long and super long-span bridges. But due to its great flexibility, the flutter stability plays an important role in the design and construction of this bridge system. Considering the geometric nonlinearity of bridge structures and the effects of nonlinear wind-structure interaction, method and its solution procedure of three-dimensional nonlinear flutter stability analysis are firstly presented. Parametric analyses on the flutter stability of a cable-stayed-suspension hybrid bridge with main span of 1400 meters are then conducted by nonlinear flutter stability analysis, some design parameters that significantly influence the flutter stability are pointed out, and the favorable structural system of the bridge is also discussed based on the wind stability.

• Mycobiology
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• v.42 no.1
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• pp.12-16
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• 2014

We isolated and examined a new Alternaria sp., which causes leaf spots on Peucedanum japonicum in Korea, by using molecular and morphological methods. Phylogenetic analysis based on a combined internal transcribed spacer region analysis and two protein-coding genes (gpd and Alt a1) demonstrated that the causal fungus was most closely related to A. cinerariae and A. sonchi, and relevant to A. brassicae. However, conidial morphology indicated that it is a novel species within the genus Alternaria, and therefore we have assigned the fungus a new name in this study.

• Mycobiology
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• v.40 no.1
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• pp.1-7
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• 2012

$Lobaria$ (Schreb.) Hoffm is a common foliose lichen genus found on the Korean Peninsula, yet until now, no revision study has been done on this genus. After careful examination of specimens deposited in the Korean Lichen Research Institute (KoLRI), nine distinct species of $Lobaria$ were confirmed. Morphological characteristics such as the presence or absence of isidia, or whether or not the surface was ridged or smooth, and chemical characteristics such as the result of the medulla reaction were of significant importance in the differentiation of species. Here, we provided detailed descriptions together with a key to all the known Korean species.

• ETRI Journal
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• v.27 no.3
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• pp.267-272
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• 2005

The transmission performance of optical labeling based on a combined frequency shift keying/amplitude shift keying (FSK/ASK) format is studied by numerical simulation. The simulation demonstrates that the bit-error ratio (BER) characteristic of an ASK signal is limited by the extinction ratio, received optical power, and dispersion, simultaneously. However, an FSK signal is mainly limited by the extinction ratio (ER) and received optical power when the peak spectrum, which is used to detect the FSK signal, is relatively narrow.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.338-341
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• 1996

A neural fuzzy control strategy, developed in order to make a Mobile Vehicle(MV) run along with the traffic guidelines on the road, is presented. A neurocomputer is used in the control procedure and it learnt the driving knowledge to control the MV's actions. The image information of the guidelines is provided by a CCD camera on the top of the MV. The MV utilize the image information to identify the shape of the road and to decide the position of itself, and control the running actions. A fuzzy controller works on-line. Both of the neural controller and the fuzzy controller make up each other. This control method solve the problem of mechanical and electrical inertia and make the Mobile Vehicle run rapidly and smoothly.

• International Journal of Control, Automation, and Systems
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• v.4 no.2
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• pp.139-145
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• 2006

A multi-variable Golden-Section adaptive controller is proposed for the tracking control of robotic manipulators with unknown dynamics. With a small sample time, the unknown dynamics of the robotic manipulator are denoted equivalently by a characteristic model of a 2-order multivariable time-varying difference equation. The coefficients of the characteristic model change slowly with time and some of their valuable characteristic relationships emerge. Based on the characteristic model, an adaptive algorithm with a simple form for the control of robotic manipulators is presented, which combines the multi-variable Golden-Section adaptive control law with the weighted least squares estimation method. Moreover, a compensation neural network law is incorporated into the designed controller to reduce the influence of the coefficients estimation error on the control performance. The results of the simulations indicate that the developed control scheme is effective in robotic manipulator control.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.673-676
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• 2003

This paper deals with the problem of moving object detection and location in computer vision. We describe a new object-dependent motion analysis method for tracking target in an image sequence taken from a moving platform. We tackle these tasks with three steps. First, we make an active contour model of a target in order to build some of low-energy points, which are called kernels. Then we detect interest points in two windows called tracking windows around a kernel respectively. At the third step, we decide the correspondence of those detected interest points between tracking windows by the probabilistic relaxation method In this algorithm, the detecting process is iterative and begins with the detection of all potential correspondence pair in consecutive image. Each pair of corresponding points is then iteratively recomputed to get a globally optimum set of pairwise correspondences.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2627-2634
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• 2012

Strobilurins are one of the most important classes of agricultural fungicides. To discover new strobilurin derivatives with high activity against resistant pathogens, a series of novel ${\beta}$-methoxyacrylate analogues were designed and synthesized by integrating substituted pyrimidine with a strobilurin pharmacophore. The compounds were confirmed and characterized by infrared, $^1H$ nuclear magnetic resonance, elemental analysis and mass spectroscopy. The bioassays indicated that most of the compounds (1a-1h) exhibited potent antifungal activities against Colletotrichum orbiculare, Botrytis cinerea Pers and Phytophthora capsici Leonian at the concentration of 50 ${\mu}g/mL$. Exhilaratingly, compound 1d (R=3-trifluoromethylphenyl) showed better antifungal activity against all the tested fungi than the commercial strobilurin fungicide azoxystrobin.