• Journal of the Korean Society of Safety
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• v.6 no.2
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• pp.5-13
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• 1991

In this paper, the interfacial stress intensity factors( $K_{i}$＝ $K_1$＋i $K_2$) for the edge interface crack in the dissimilar materials(isotropic-isotropic materials, isotropic-composite materials) were analysed by BEM(Boundary Element Method). The fatigue crack growth behaviour was investigated by load constant fatigue test. From the experimental results, the relationship between da/dN and interfacial stress intensity facto, ( $K_{i}$ or $K_1$) can be expressed by Paris'law for homogeneous materials.s.s.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.2
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• pp.107-111
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• 2007

A two-dimensional numerical method for inviscid two-fluid flows with evolution of density interface is developed, and an initially stationary two-dimensional fluid sheet surrounded by another fluid is studied. The interface between two fluids is modeled as a vortex sheet, and the flow field with the evolution of interface is solved by using vortex-in-cell/front-tracking method. The edge of the sheet is pulled back into the sheet due to surface tension and a blob is formed at the edge. This blob and fluid sheet are connected by a thin neck. In the inviscid limit, such process of the blob and neck formation is examined in detail and their kinematic characteristics are summarized with dimensionless parameters. The edge recedes at and the capillary wave propagating into the fluid sheet must be considered for better understanding of the edge receding.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.10a
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• pp.254-260
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• 1998

Application of bonded dissimilar materials in various industries are increasing. When these materials are used in structures, it needs to investigate strength evolution applying fracture mechanics. Al/Epoxy bonded dissimilar materials with an interface crack and an interface crack emanating from an edge semicircular hole were prepared for the static tests so that experiment of fracture toughness were carried out. Stress intensity factors of interface cracks in bonded dissimilar materials were computed with boundary element method(BEM) and the fracture criterion of mixed mode crack were analyzed. From the results, the fracture criterion and the method of strength evolution by the fracture toughness in Al/Epoxy bonded dissimilar materials were proposed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.4 no.4
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• pp.50-60
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• 1995

Recently advantages joining dissimiliar materials and light weight material techniques have led to increasing use of structural adhesives in the various industries. Stress singulartiy occurs at the interface edges of adhesively bonded dissimilar materials. So it is required to analyze its stress singularity at the interface edges of adhesively bonded joints indissimilar materials. In this paper, the analysis method of stress singularity is studied in detail. Also, effects of the stress singularity at the interface edge of adhesively bonded scarf joints in combinations of dissimilar materials are investigated by using 2-dimensional elastic program of boundary element method. As the results, the strength evaluation method of adhesively bonded dissimilar materials using the stress singularity factor, $\Gamma$,is very useful. The fracture criterion, method of strength evaluation and prediction of fracture strength by the stress singularity factor on the adhesively bonded dissimilar materials are proposed.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.2
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• pp.142-148
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• 2005

In this paper, the stress singularity on interface of friction welded dissimilar materials was investigated by using 2-dimensional elastic boundary element method. It is required that stress distributions and stress singularities on an interface for friction welded dissimilar materials analize to establish strength evaluation. The stress singularity index ($\lambda$) and stress singularity factor ($\Gamma$) were calculated from the results of stress analysis. The stress singularities on variations for shapes and thickness of friction welded flashes were analized and discussed. This paper suggested that the strength evalution by using the stress singularity factors as fracture parameters, considering the stress singularity on an interface edge of friction welded dissimilar materials were very useful.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.3
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• pp.25-30
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• 2001

The stress intensity factors for edge cracks located at the bonding interface between the semiconductor chip and the adhesive layer subjected to a uniform transverse tensile strain are investigated. Such cracks might be generated due to a stress singularity in the vicinity of the free surface. The boundary element method (BEM) is employed to investigate the behavior of interface stresses. The amplitude of complex stress intensity factor depends on the crack length, but it has a constant value at large crack lengths. The rapid propagation of interface crack is expected if the transverse tensile strain reaches a critical value.

• Journal of IKEEE
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• v.21 no.3
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• pp.256-259
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• 2017

SENT (single edge nibble transmission) is a serial communication protocol between automotive sensors and ECU (electronic control unit). SENT exploits digital waveform, so it has a simple and cheap architecture without transceiver circuits. Usually it is exploited as an embedded communication interface in the sensors. In this paper, a SENT interface was designed in Verilog HDL, fully complying with SAE J2716. It was implemented in FPGA, and verified on a test board. When it was synthesized, the gate count is about 2,500 gates in 0.18um technology.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.11C
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• pp.1171-1177
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• 2002

In this paper, we proposed a high speed IP(Internet Protocol) packet forwarding engine of ATM(Asynchronous Transfer Mode) based label edge routers for POS(Packet over SONET) interface. The forwarding engine uses TCAM(Ternary Content Addressable Memory) for high performance lookup processing of the packet received from POS interface. We have accomplished high speed IP packet forwarding in hardware by implementing the functions of high speed IP header Processing and lookup control into FPGA(Field Programmable Gate Array). The proposed forwarding engine has the functions of label edge routers as the lookup controller supports MPLS(Multiprotocol Label Switching) packet processing functionality.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.20 no.2
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• pp.137-150
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• 2016

In this paper we analyze an a posteriori error estimator based on flux recovery for lowest-order finite element discretizations of elliptic interface problems. The flux recovery considered here is based on averaging the discrete normal fluxes and/or tangential derivatives at midpoints of edges with weight factors adapted to discontinuous coefficients. It is shown that the error estimator based on this flux recovery is equivalent to the error estimator of Bernardi and $Verf{\ddot{u}}rth$ based on the standard edge residuals uniformly with respect to jumps of the coefficient between subdomains. Moreover, as a byproduct, we obtain slightly modified weight factors in the edge residual estimator which are expected to produce more accurate results.

• Computational Structural Engineering
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• v.8 no.3
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• pp.75-78
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• 1995

The boundary element analysis has been attempted for investigating the singular stress at the interface edge of infinitely layered structure. The subdomain technique has been employed and the analysis model has been divided into two subdomains, which are respectively homogeneous elastic zones. The boundary element equation has been formulated using the equilibrium and continuity conditions at the common interface. The numerical results of example problem has been presented.