• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.632-632
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• 2013

We generated single-crystal organic nanowire arrays using a direct printing method (liquidbridge- mediated nanotransfer molding) that enables the simultaneous synthesis, alignment and patterning of nanowires from molecular ink solutions. Using this method, single-crystal organic nanowires can easily be synthesized by self-assembly and crystallization of organic molecules within the nanoscale channels of molds, and these nanowires can then be directly transferred to specific positions on substrates to generate nanowire arrays by a direct printing process. The position of the nanowires on complex structures is easy to adjust, because the mold is movable on the substrates before the polar liquid layer, which acts as an adhesive lubricant, is dried. Repeated application of the direct printing process can be used to produce organic nanowire-integrated electronics with twoor three-dimensional complex structures on large-area flexible substrates. This efficient manufacturing method is used to fabricate all-organic nanowire field-effect transistors that are integrated into device arrays and inverters on flexible plastic substrates.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.8
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• pp.27-33
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• 2004

A new multicast scheme for mobile nodes is proposed to support real-time communication in a more efficient way. In the proposed multicast scheme, the Xcast (a very flexible data plane mechanism) is integrated with the SIP (a very flexible control plane protocol) to support multicast for mobile nodes. The simulation results verify that the proposed scheme reduces unnecessary network traffic and achieves low latency of packets in the network.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.676-679
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• 2006

The media transport in automatic office machines such as printers, ATMs, copying machines is achieved by a complicated belt system. The system generally uses a crowning roller and belt which has been well-known for its intrinsic belt centering advantage during its operation. Since the modern office machines require precise high operating speed, stabilization of media transporting system has been one of the important issues of the machine design. Even a minor defect of the belt or the roller in the transport system directly affects its operating stability. This paper delivers a simulation technique that combines a multi-body dynamics analysis routine and a FEM based flexible continuum modeling for the efficient simulation of the flexible media transport problems.

• Computational Structural Engineering
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• v.2 no.1
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• pp.47-53
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• 1989

An efficient model for three-dimensional analysis of multistory structures with flexible floor diaphrgms is proposed in this paper. Three-dimensional analysis of a building structure using a finite element model requires tedious input data preparation, longer computation time, and larger computer memory. The model proposed in this study is developed by assembling a series of two-dimensional resisting systems and is considered to overcome the shortcomings of a three-dimensional finite element model without deteriorating the accuracy of analysis results. Static and dynamic analysis results obtained using the proposed model are in excellent agreement with those obtained using three-dimensional finite element models in terms of displacement, periods, and mode shapes. Effects of floor diaphragm flexibility on seismic response of multistory building structures are investigated.

• Proceedings of the Korea Society for Simulation Conference
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• 1998.10a
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• pp.128-132
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• 1998

This research is concerned with buffer management in a multi-cell FMS(Flexible Manufacturing System) with an AGVS(Automated Guided Vehicle System). To reduce blocking and starving caused by breakdowns, variablility in process times, and diversity of part routing, buffer is needed. Due to the high per unit buffer cost, which primarily consists of floor space and equipment cost, the total capacity of buffers in an FMS is very limited. Therefore, proper buffer management can provide a high system efficiency. This paper presents a buffer management model for a multi-cell FMS with an AGVS and a simulation study to compare the proposed model to a conventional buffer management model in a job shop FMS.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2566-2569
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• 2003

An alternative optimal control law formulation is introduced and compared with two different control law, a conventional linear quadratic regulator and the control law based on game theory. This formulation eliminates the undesired modes of the system by the projection of a controller onto the subspace orthogonal to that of the bad modes. In conventional LQR control law, the control performance can be improved only by using proper weighting matrices in performance index, normally, with high cost. The control law formulation by game theory may provide various ways to obtain the desired performance. The control law modified by the elimination of bad modes provides efficient ways to get rid of an undesired performance since it eliminates the exact modes which cause the bad control performance.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1988.10a
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• pp.13-17
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• 1988

An efficient model for three-dimensional analysis of multistory structures with flexible floor diaphragms is proposed in this paper. Three-dimensional analysis of a building structure using a finite element model requires tedious input data preparation, longer computation time, and larger computer memory. The model proposed in this study is developed by assembling a series of two-dimensional resisting systems and is considered to overcome the shortcomings of a three-dimensional finite element model without deteriorating the accuracy of analysis results. Static and dynamic analysis results obtained using the proposed model are in excellent agreements to those obtained using three-dimensional finite element models in terms of displacements, periods, mode shapes.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.2
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• pp.120-128
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• 2011

This paper presents an efficient method to analyze noise and vibration of marine diesel engines mounted on flexible hull structure. The analysis model should in general include the hull structure, leading to lots of computational efforts. To minimize the computational efforts, in this paper, the transfer synthesis utilizing the receptance at the mounting points is proposed. The procedure is then verified by comparing the results with those from the full model calculation. The effects of flexible hull structure on the acoustic power from engine block are finally investigated. It is found that the effect of the hull is significant when the receptance of hull structure is similar to or greater than that of mount or engine block.

• Smart Media Journal
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• v.6 no.3
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• pp.89-94
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• 2017

The existing geofences provide only context-awareness service for entering or leaving the set region when a user sets a virtual region for his/her PoI(Point of Interest). Applying the mobile-geofence technology to the connected car technology, which is attracting attention as a next generation technology, it is possible to provide application service without additional infrastructure construction cost However, to do this, we need to expand and improve the functions of traditional geofence. In this paper, we propose and implement a flexible mobile-geofence in which the radii of each geofence applied to vehicles is changed according to context-aware in order to support connected cars technology based on the previously studied mobile three-dimensional geofence system. The proposed flexible mobile-geofence shows experimentally that the region of the geofence is changed according to context-aware of itself and its surroundings after applying a flexible decision algorithm by the flexible factor analysis. In the future, we are expected that the flexible mobile-geofence proposed in this paper will be applied not only to connected-cars technology but also to the application technology of V2X(Vehicle to Everything) for safe and efficient vehicle operation.

• 한국전산유체공학회:학술대회논문집
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• 2005.10a
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• pp.99-104
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• 2005

For the efficient reliability analysis, Bi-direction two-point approximation(BTPA) method is developed which solves shortcomings of conventional two-point approximation(TPA) methods that generate an approximate surface with low accuracy or sometimes do an unstable approximate surface. The conventional reliability based design optimization(RBDO) methods require high computational cost compared with the deterministic design optimization(DO) methods. To overcome the computational inefficiency of RBDO, the approximate reliability analysis approaches on the TPA surface are proposed. Using these FORM and SORM analysis strategies, multi-point aerodynamic-structure interacted shape design optimizations with uncertainty are performed very efficiently.