• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.109-112
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• 2007

To determine design or remaining life of flexible pavement, tensile strain at the bottom of asphalt concrete course and vertical strain on top of subgrade should be estimated. Various computer programs can be used for determining the strain at the critical position in pavement. However, these are conducted under the assumptions of full bonded or unbound state of layer interface conditions. This study compares the output of finite element analysis and multi-layer elastic analysis as vertical load was applied to the surface of flexible pavement. It is noted that the pavement performance is significantly affected depending upon the interface conditions.

• Journal of KIISE:Information Networking
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• v.32 no.2
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• pp.203-214
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• 2005

The integration of 3G networks and WLANs as complementary has been begun to attract much attention in industry as well as academia. This topic is becoming a burning issue, and one of the key questions which it raises is how to support a seamless vertical handoff. This paper introduces a new network interface selection algorithm for energy-efficient vertical handoff in tightly coupled systems capable of supporting seamless handoff. Our proposed scheme, Wise Interface Selection (WISE) switches the active network interface, after taking into consideration the characteristics of the network interface cards and the current level of data traffic, with the cooperation of the mobile terminals and network. Network interface switching operates independently on both the downlink and the uplink for the purpose of energy conservation. We show through simulation that less energy is consumed with WISE than when only a 3G network or WLAN interface is used, resulting in a longer lifetime for the mobile terminals. In the case of TCP connections, additional throughput gain can also be obtained.

• The Transactions of the Korea Information Processing Society
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• v.4 no.4
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• pp.1100-1105
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• 1997

The verial black stripe is one of the defects in a chrge-coupled device(CCD). Vertical black stripes are caused by some signal chrges which fail to transport form the vertical CCD region to the horizontal one. The defective transport of signal charges orignates in the potential barrier with the narrow width effects in the verti-cal-horizintal interface stuccture. The vertical black stripes show up when the charge transfer dfficiency is less than 99.2% under the low illumination condition. In this research, we designed and developed a new vertical-horizontal interface structre of a delta type, thus marking it possible to eliminate the vertical black stripes.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.92-96
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• 2001

Although the problem of seawater intrusion at the coastal aquifer was recognized before over one hundred years at the coastal aquifer, much groundwater keep on being salinitized by several reasons such as groundwater exhaustion, coastalline change, and human activities. The horizontal and vertical electrical soundings and geostatistical methods were used to define the local characteristics of saltwater intrusion and to estimate the saltwater interface in the southeastern area of the Pusan City. The 24 points of the Schlumberger vertical electrical soundings(VES) to loom depth and the 2 lines of dipole-dipole horizontal soundings are peformed. The resistivity data have lognormal distributions. The horizontal extents of saline water intrusion were estimated from the inversion of horizontal prospecting data. Lognormal ordinary kriging is used in A-A' resistivity profiles on May and July because the data have stationary models in semivariograms. Lognormal IRF-k kriging is used for the isopleth maps using vertical resistivity data. The 10 ohm-m resistivity line on the isopleth maps of 21m, 30m, 50m, and 70m depth using resisitivity data measured in July is sifted to the east, cpomparing that of the isopleth maps measured in May. The kriged vertical and horizontal resistivity isopleth maps suggested that the geostatistical methods can be used to define the variation of earth resistivity distribution at the saltwater interface.

• Journal of Internet Computing and Services
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• v.3 no.5
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• pp.9-17
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• 2002

CSIX-L1 is the Common Switch Interface that defines a physical interface for transferring information between a traffic manager (Network Processor) and a switching fabric in ATM, IP, MPLS, Ethernet and data communication areas. In Tx, data to be transmitted is generated in Cframe which is the base information unit and in Rx, original data is extracted from the received Cframe. CSIX-L1 suppots the 32, 64, 96, and 123-bit interface and generates a variable length CFrame and Idle Cframe. Also CSIX-L1 appends Padding byte and supports 16-bit Vertical parity, CSIX-L1 is designed using Xilinx 4,1i. After functional and timing simulations are completed. CSIX-L1 module is downloaded in Xilinx FPGA XCV1000EHQ240C and verified. The synthesized CSIX module operates at 27MHz.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.7 s.94
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• pp.1794-1804
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• 1993

The thermal stress intensity factors for interface cracks of Griffith and symmetric lip cusp types under vertical uniform heat flow in a finite body are calculated by boundary element method. The boundary conditions on the crack surfaces are insulated or fixed to constant temperature. The relationship between the stress intensity factors and the displacements on the nodal point of a crack tip element is derived. The numerical values of the thermal stress intensity factors for interface Griffith crack in an infinite body and for symmetric lip cusp crack in a finite and homogeneous body are compared with the previous solutions. The thermal stress intensity factors for symmetric lip cusp interface crack in a finite body are calculated with respect to various effective crack lengths, configuration parameters, material property ratios and the thermal boundary conditions on the crack surfaces. Under the same outer boundary conditions, there are no appreciable differences in the distribution of thermal stress intensity factors with respect to each material properties. But the effect of crack surface thermal boundary conditions on the thermal stress intensity factors is considerable.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.12
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• pp.3949-3959
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• 1996

A new interfacial instability between two vertical fluid layers of different densities is studied. The two layers are flowing between two parallel vertical plates vertically upward or downward, forming counter- or concurrent flows. In order to extend the study to highly-nonlinear regime in future studies, a nonlinear interface evolution equation is derived, and the stability analysis is performed based on the evolution equation. Among the parameters studies are the ratios of the fluid densities and layer thicknesses and the net flow rate.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.201-208
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• 1991

In case that an interface crack exists in an infinite two-dimensional elastic bimaterial, the crack surface is insulated under traction free and the uniform heat flow vertical to the crack from infinite boundary is given. Temperature and stress potentials are obtained by using complex variable approach to solve Hilbert problems. The results are used to obtain thermal stress intensity factors. Only mode I thermal stress intensity factor occurs in case of the homogeneous material. Otherwise, mode I and II thermal stress intensity factor is much smaller than one of mode II.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.4
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• pp.1095-1101
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• 1995

Numerical analysis of vertical solidification process allowing solid-liquid density change is performed by a hybrid method between a winite volume method (FVM) and a finite element method (FEM). The investigation focuses on the influence of solid-liquid density change and cooling rates on the motion of solid-liquid interface, solidified mass fraction, temperatures and thermal stresses in the solid region. Due to the density change of pure aluminium, solid-liquid interface moves more slowly but the solidified mass fraction is larger. The cooling rate of the wall is shown to have a significant influence on the phase change heat transfer and thermal stresses, while the density change has a small influence on the motion of the interface, solidified mass fraction, temperature distributions and thermal stresses. As the cooling rate increases, the thermal stresses become higher at the early stage of a solidification process, but it has small influence on the final stresses as the steady state is reached.

• Journal of Mechanical Science and Technology
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• v.15 no.8
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• pp.1188-1195
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• 2001

A numerical analysis has been carried out to investigate the influences of thermosolutal convection on the heat and mass transfer and solute segregation in crystals grown by the vertical Bridgman technique. The governing equations are solved by a finite-volume method using the power law scheme and the SIMPLE algorithm in which body-fitted coordinate system has been used. A primary convective cell driven by thermal gradients forms in the bulk of the domain, while a secondary convective cell driven by solutal gradients forms near interface. As the solutal Rayleigh number increases, secondary cell becomes to be stronger and has a great influence on the radial concentration along the interface.