• Journal of the Korea Society for Simulation
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• v.4 no.1
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• pp.59-73
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• 1995

Local area networks(LANs) recently become so large that they exceed their architected limits and users on different LANs may need to talk each other. This trend has led to a growth in the practice of interconnecting many heterogeneous LANs. In this paper, we proposed a method to interconnect Ethernets and token rings, which are widely used today, through a fast FDDI network. We also developed a simulation tool to evaluate the performances of the interconnected networks. We used a simulation language SLAM II for modeling and OSF/MOTIF X-window for user interface. The developed tool can be used to make a decision which interconnecting method is suitable for a given environment before interconnecting many heterogeneous LANs.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.24 no.2
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• pp.199-214
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• 2020

This paper describes the development of a parallel computational algorithm based on the finite element tearing and interconnecting (FETI) method that uses a local Lagrange multiplier. In this approach, structural computational domain is decomposed into non-overlapping sub-domains using local Lagrange multiplier. The local Lagrange multipliers are imposed at interconnecting nodes. 8-node solid element using extra shape function is adopted by using the representative volume element (RVE). The parallel computational algorithm is further established based on message passing interface (MPI). Finally, the present FETI-local approach is implemented on parallel hardware and shows improved performance.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.58.1-58.1
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• 2012

Direct write technologies provide flexible and economic means to manufacture low-cost large-area electronics. In this regard inkjet printing has frequently been used for the fabrication of electronic devices. Full advantage of this method, which is capable of reliable direct patterning with line and space dimensions in the 10 to 100 um regime, is only made with all-solution based processing. Among these printable electronic materials, silver and copper nanoparticles have been used as interconnecting materials. Specially, solutions of organic-encapsulated silver and copper nanoparticles may be printed and subsequently annealed to form low-resistance conductor patterns. In this talk, we describe novel processes for forming silver nanoplates and copper ion complex which have unique properties, and discuss the optimization of the printing/annealing processes to demonstrate plastic-compatible low-resistance conductors. By optimizing both the interconnecting materials and the surface treatments of substrate, it is possible to produce particles that anneal at low-temperatures (< $200^{\circ}C$) to form continuous films having low resistivity and appropriate work function for formation of rectifying contacts.

• Journal of Korea Spatial Information System Society
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• v.7 no.2 s.14
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• pp.57-66
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• 2005

The Interconnecting Highways problem is an abstract of many practical Layout Design problems in the areas of VLSI design, the optical and wired network design, and the planning for the road constructions. For the road constructions, the shortest-length road layouts that interconnect existing positions will provide many more economic benefits than others. That is, finding new road layouts to interconnect existing roads and cities over a wide area is an important issue. This paper addresses an approximation scheme that finds near optimal road layouts for the Interconnecting Highways problem which is NP-hard. As long as computational resources are provided, the near optimality can be acquired asymptotically. This implies that the result of the scheme can be regarded as the optimal solution for the problem in practice. While other approximation schemes can be made for the problem, this proposed scheme provides a big merit that the algorithm designed by this scheme fits well to given problem instances.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.6
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• pp.49-57
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• 2010

In the near future IPTV services will be emerged the various types through Internet, but IMS based IPTV service is one of the very attractive IPTV services. This paper describes the interconnecting architectures of Web based IPTV contents provider to IMS(IP Multimedia System) network and describes the three difference architectures as method to find its IP address. One is the architecture using DNS or HSS to find IP address of Web based IPTV contents provider and connecting gateway function to I-CSCF in IMS. The other is the architecture connecting gateway AS to ISC interface of S-CSCF in IMS. This paper describes the characteristics of traffic generating due to interconnect the Web contents provider, and the traffic model of each architectures. The proposed each architecture is emulated the session establishment delay characteristics in CoD service of IPTV by the simulation. This paper shows that the architecture connecting gateway AS to ISC interface of S-CSCF is the excellent method compare to other two methods in view of the session establishment delay.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.12
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• pp.1878-1888
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• 1990

In this paper, the input-output interconnection method of the multi-valued signal processing circuit using perfect Shuffle technique and Kronecker product is discussed. Using this method, the design method of circuit of the multi-valued Reed-Muller expansions(MRME) to be used the multi-valued signal processing on finite field GF(p**m) is presented. The proposed input-output interconnection method is shown that the matrix transform is efficient and that the module structure is easy. The circuit design of MRME on FG(p**m) is realized following as` 1) contructing the baisc gates on GF(3) by CMOS T gate, 2) designing the basic cells to be implemented the transform and inverse transform matrix of MRME using these basic gates, 3) interconnecting these cells by the input-output interconnecting method of the multivalued signal processing circuits. Also, the circuit design of the multi-valued signal processing function on GF(3\ulcorner similar to Winograd algorithm of 3x3 array of DFT (discrete fourier transform) is realized by interconnection of Perfect Shuffle technique and Kronecker product. The presented multi-valued signal processing circuits that are simple and regular for wire routing and posses the properties of concurrency and modularity are suitable for VLSI.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.6
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• pp.693-702
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• 2010

In this paper, FETI(Finite Element Tearing and Interconnecting) method is introduced in order to improve numerical efficiency of Staggered method. The porous media theory, the Staggered method and the FETI method are briefly introduced in this paper. In addition, we account for the MPI(Message Passing Interface) library for parallel analysis, and the proposed combined Staggered method with FETI method. Finally Lagrange multipliers and CG(Conjugate Gradient) algorithm to solve decomposed domain are proposed, and then the proposed method is verified to be numerically efficient by MPI library.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.4
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• pp.369-378
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• 2010

The mixed finite element analysis is the most widely used method for saturated porous media. Generally, in this method, direct method and iterative method are proposed to obtain unknown variable, however, the iterative method is recommended because the method provide numerical stability and accuracy under the material properties for solid and fluid are different. In this paper, we introduce staggered method which has strong numerical stability, and FETI(Finite Element Tearing and Interconnecting) which is one of decomposition methods are applied into the method in order to obtain numerical efficiency. In which, Lagrange Multipliers and conjugated gradient method to solve decomposed domain are proposed, and then, the proposed method is verified numerical efficiency by point to point MPI(Message Passing Interface) library.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.410.2-410.2
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• 2016

Tandem structure is promising in organic solar cells because of its double open-circuit voltage (VOC) and efficient photon energy conversion. In a typical tandem device, the two single sub-cells are stacked and connected by an interconnecting layer. The fabrication of two sub-cells are usually carried out in a glovebox filled with nitrogen or argon gas, which makes it expensive and laborious. We report a glovebox-free fabricated inverted tandem organic solar cells wherein the tandem structure comprises sandwiched interconnecting layer based on p-doped hole-transporting, metal, and electron-transporting materials. Complete fabrication process of the tandem device was performed outside the glove box. The tandem solar cells based on poly(3-hexylthiophene) (P3HT) and (6,6)-phenyl C61-butyric acid methyl ester (PCBM) can realize a high VOC, which sums up of the two sub-cells. The tandem device structure was ITO/ZnO/P3HT:PCBM/PEDOT:PSS/MoO3/Au/Al/ZnO-d/P3HT:PCBM/PEDOT:PSS/Ag. The separate sub-cells were morphologically and thermally stable up to 160 oC. The high stability of the active layer benefits in the fabrication processes of tandem device. The performance of tandem organic solar cells comes from the sub-cells with an 50 nm thick active layer of P3HT:PCBM, achieving an average power conversion efficiency (PCE) of 2.9% (n=12) with short-circuit current density (JSC) = 4.26 mA/cm2, VOC = 1.10 V, and fill factor (FF) = 0.62. Based on these findings, we propose a new method to improve the performance and stability of tandem organic solar cells.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.12
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• pp.675-683
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• 2003

This paper describes the correction strategy of an overcurrent relay applied in the linked line for interconnecting wind farm with utility power networks in order to improve the capability of a fault detection. The fault current measured in a relaying point might vary according to the fault conditions. Generally, the current of the line to line fault or the line to ground fault in the linked line is much higher than the set value of protective relay due to the large fault level. However, when the high impedance fault occurs in the linked line, we can't detect it by conventional set value because its fault level may be lower than the generating capacity of wind farm. And, the protective relay with conventional set value may generate a trip signal for the insertion of wind turbine generators due to the large transient characteristics. In order to solve above problems and improve protective relaying algorithms applied in the linked line, we propose a new correction strategy of the protective relay in the linked line. The presented method can detect the high impedance fault which can't be detected by conventional relay set value and may prevent the mis-operation of protective relay caused by the insertion of wind farm.