• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2001.11b
• /
• pp.1215-1220
• /
• 2001

Wind tunnel test of a new pantograph, that is developed through the KHST project, was performed in RTRI wind tunnel test center of Japan end of last June. This paper indtroduces the measurement results and analysis of noise measurement part that is achieved during the wind tunnel test. The maximum measured sound pressure level at 5m shows 102.3dB(A) at 350km/h and it leads to 88.3dB(A) of predicted sound pressure at 25m that satisfy 91dB(A) of evaluation criteria. Major noise sources of the pantograph was identified as a link between upper and lower arm, panhead contact strips and shunt wires.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.10 no.2
• /
• pp.75-82
• /
• 2000

This paper presents a method of detecting surface flaw of cold-rolled steel plate using image processing technique and a neural network classifier. The amount of steel plate surface image data is reduced by the wavelet transform. Features are extracted from the co-occurence matrix of the partial image corresponding to the low-frequency region, and a MLP neural network classifies into predetermined surface flaw categories. Simulations show the neural network classifier outperforms conventional vector quantization method.

• Bulletin of the Korean Mathematical Society
• /
• v.51 no.4
• /
• pp.1229-1240
• /
• 2014

In this paper we provide three results involving large Schr$\ddot{o}$der paths. First, we enumerate the number of large Schr$\ddot{o}$der paths by type. Second, we prove that these numbers are the coefficients of a certain symmetric function defined on the staircase skew shape when expanded in elementary symmetric functions. Finally we define a symmetric function on a Fuss path associated with its low valleys and prove that when expanded in elementary symmetric functions the indices are running over the types of all Schr$\ddot{o}$der paths. These results extend their counterparts of Kreweras and Armstrong-Eu on Dyck paths respectively.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.1802-1807
• /
• 2005

Tangible interface can be understood as a newly defined concept, which can provide an effective and seamless interaction between the human as a subjective existence and the cyberspace as an objective existence. Tactile sensation is essential for many exploration and manipulation tasks in the tangible space. In this paper, we suggest the design of an integrated tactile sensor-display system that provides both of sensing and feedback with kinesthetic force, pressure distribution, vibration and slip/stretch. A new tactile sensor with PDVF strips and display system with bimorph actuators has been developed and integrated by developed signal processing algorithm. In the scenario of haptic navigation in the tangible space, tactile feedback system is successfully experimented.

• Proceedings of the KSR Conference
• /
• 2011.05a
• /
• pp.1336-1341
• /
• 2011

The pantograph-overhead contact line system is an interface that supplies power to high-speed trains used in many countries including Korea. Due to the fact that power is supplied through direct contact between contact wires and contact strips, wear may occur, increasing the possibility of accidents over periods of time. Therefore, there is a need to establish methods of effectively extracting safety related parameters. In this paper, an image processing based method that calculates and draws graphs of a pantograph's dynamic stagger is proposed. To assess reliability, the results were compared with data collected from conventional maintenance vehicles.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.15 no.8
• /
• pp.794-800
• /
• 2004

In this paper a new approximate formulation for bistatic scattering by a thin dielectric strip for TM wave incidence is obtained. This formulation is uniform which is valid for any incident angles, observation points, and any properties of the skip such as dielectric constants, width, and thickness. The accuracy of the proposed solution is examined by comparisons with a method of moments(MoM) for various situations.

• Structural Engineering and Mechanics
• /
• v.31 no.3
• /
• pp.277-296
• /
• 2009

The paper investigates the dynamic behaviour of stiffened panels. The coupled differential equations for eccentric stiffening configuration are first derived. Then a semi-analytical procedure for dynamic analysis of stiffened panels is presented. Unlike finite element or finite strip methods, where the plate is discretized into a set of elements or strips, the plate in this procedure is treated as a single element. The potential energy of the structure is first expressed in terms generalized functions that describe the longitudinal and transverse displacement profiles. The resulting non-linear strain energy functions are then transformed into unconstrained optimization problem in which mathematical programming techniques are employed to determine the magnitude of the lowest natural frequency and the associated mode shape for pre-selected plate/stiffener geometric parameters. The described procedure is verified with other numerical methods for several stiffened panels. Results are then presented showing the variation of the natural frequency with plate/stiffener geometric parameters for various stiffening configurations.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2005.05a
• /
• pp.99-102
• /
• 2005

This paper presents test results on strengthening details of reinforced concrete beams strengthened with near-surface mounted(NSM) CFRP rod and strip. A total of 8 specimens have been tested. The specimens can be classified into the same strengthening area group and the different spacing group. For the same strengthening area group, experimental results revealed that specimens strengthened with NSM CFRP strips improved the flexural capacity of RC beams. For the different spacing group, the flexural capacity of RC beams was almost the same, but it was different in case of NSM CFRP rods.

• Structural Engineering and Mechanics
• /
• v.12 no.3
• /
• pp.313-328
• /
• 2001

A multi-span bridge has the peak value of resultant girder moment or membrane stress at the interior support. In this paper, the spline finite strip method (FSM) is modified to obtain the more appropriate solution at the interior support where the peak values of solution exist. The modification has been achieved by expressing the shape function with non-periodic B-splines which have multiple knots at the boundary. The modified B-splines have the useful feature for interpolating the curve with sudden change in curvature. Moreover, the modified spline FSM is very efficient in analyzing multi-span box girder bridges, since a bridge can be modeled by an assembly of strips extended along the entire bridge length. Numerical examples of the bridge analysis have been performed to verify the efficiency and accuracy of the new spline FSM.

• Journal of Sensor Science and Technology
• /
• v.22 no.5
• /
• pp.369-373
• /
• 2013

In this paper, we developed contact type temperature sensor with single crystal silicon strip thermopile. This sensor consists of 15 p-type single crystal silicon strips, 17 n-types and contact electrodes on silicon dioxide silicon membrane. The result of electromotive force measuring showed very good characteristic as $15.18mV/^{\circ}C$ when temperature difference between the two ends of the thermopile occurs by applying thermal contact on the thermopile which was fabricated with silicon strip of $200{\mu}m$ length, $20{\mu}m$ width, $1{\mu}m$ thickness.