• IEIE Transactions on Smart Processing and Computing
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• v.4 no.6
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• pp.391-402
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• 2015

In this paper, we present implementation of backward movement control of truck-trailer vehicles using a fuzzy mode-based control scheme considering practical constraints and computational overhead. We propose a fuzzy feedback controller where output is predicted with the delay of a unit sampling period. Analysis and design of the proposed controller is very easy, because it is synchronized with sampling time. Stability analysis is also possible when quantization exists in the implementation of fuzzy control architectures, and we show that if the trivial solution of the fuzzy control system without quantization is asymptotically stable, then the solutions of the fuzzy control system with quantization are uniformly ultimately bounded. Experimental results using a toy truck show that the proposed control system outperforms a conventional system.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.36.1-36.1
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• 2013

I present a simple scheme for the treatment of gravitational interactions on galactic scales. In analogy with known mechanisms of quantum field theory, I assume ad hoc that gravitation is mediated by virtual exchange particles - gravitons - with very small but non-zero masses. The scheme predicts the asymptotic flattening of galactic rotation curves, the Tully-Fisher/Faber-Jackson relations, the mass discrepancy-acceleration relation of galaxies, and the surface brightness-acceleration relation of galaxies correctly; additional (dark) mass components are not required. The well-established empirical scaling laws of Modified Newtonian Dynamics follow naturally from the model. The scheme I present is not a consistent theory of gravitation; rather, it is a toy model providing a convenient scaling law that simplifies the description of gravity on galactic scales.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.238-242
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• 2002

In this paper. we consider an OFDM system with cochannel interference and the use of adaptive antenna arrays to suppress such interference. Based on the conventional RLS criterion, we derive a new Recursive Least Square (RLS) adaptive beamforming algorithm for antenna arrays applied in an OFDM system. Computer simulation shows that. when applied to the OFDM system. the proposed algorithm is capable of combating cochannel interference in both AWGN channel and multipath Rayleigh fading channel with AWGN.

• Journal of Communications and Networks
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• v.14 no.2
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• pp.169-178
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• 2012

In this paper, we study the advantages of using range extension cooperative transmission (CT) in multi-hop energy harvesting wireless sensor networks (EH-WSNs) from the network layer perspective. EH-WSNs rely on harvested energy, and therefore, if a required service is energy-intensive, the network may not be able to support the service successfully. We show that CT networks that utilize both range extension CT and non-CT routing can successfully support services that cannot be supported by non-CT networks. For a two-hop toy network, we show that range extension CT can provide better services than non-CT. Then, we provide a method of determining the supportable services that can be achieved by using optimal non-CT and CT routing protocols for EH-WSNs. Using our method and network simulations, we justify our claim that CT networks can provide better services than nonCT networks in EH-WSNs.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2956-2958
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• 2000

This paper describes the design of a real time traffic data acquisition system using loop detector and piezzo sensor. Loop detector is the cheapest method to measure the speed and piezzo is used to detect the vehicle axle information. A ISA slot based I/O board is designed for data acquisition and PC process the raw traffic data and transfer the data to the host system. Simulation kit is designed with toy car kits. simulated loop detector and piezzo sensor. The data acquisition system collects up to 10 lane highway traffic data such as vehicle count. speed. length axle count. distance between the axles. The data is processed to generate traffic count, vehicle classification, which are to be used for ITS. The system architecture and simulation data is included and the system will be tested for field operation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.341-346
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• 2002

The production part requiring multiple processes such as piecing, blanking and notching are performed with a high production rates in progressive die. In order to prevent the defects of process result, the optimum of strip process layout design, die design, die making, and tryout with inspection etc. are needed. According to these factors of die development process, they required theory and practice of metal working process and its background, die structure, machining conditions for die making, die materials, heat treatment of die components, know-how and so on. In this study, we designed and analyzed die components also simulated the strip process layout of multiple stage drawing by DEFORM. Especially the result of tryout and its analysis become to the feature of this study.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.551-562
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• 2000

The study was carried out about the design of power Car for Korean High Speed Train of maximum operating speed of 350km/h. The running resistance accounts toy the greater part of overall resistance to front hue motion. So, The Power Car's shape has to be mainly determined by aerodynamic considerations. In the train configuration of the KHST, the front and rear power cars assume the role of a locomotive. They accommodate all the machinery for providing traction. The train is controlled and monitored from power cars. This report was descrived, which focuses on aerodynamics, mass balance, the car body and the layout of the equipment that is fitted into power car.

• Korean Journal of Child Studies
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• v.18 no.2
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• pp.87-103
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• 1997

The purposes of this study were to investigate the quality of toys, to explore children's and mothers' perception of toys, and to present future directions for toy manufacturers, children and mothers. The subjects were 127 6-year-old, 143 8-year-old, 151 10-year-old children and 383 mothers. In addition, 113 toys were selected for analysis. Data were gathered through both observations and questionnaires. The results showed that most toys were appropriate to stimulate cognitive development. However, for dolls, 90% of them were in the shape of Caucasions. Children who were accustomed to such dolls may develop the tendency to favor a Western aesthetic standard. War toys, such as guns and robots may provoke aggression and violence. Mothers believed that toys should be helpful for the intellectual, social and physical development of children. While mothers were not satisfied with the quality of domestically produced toys, children generally liked them.

• Journal of Biomedical Engineering Research
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• v.22 no.6
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• pp.527-534
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• 2001

Conventional stereo image acquisition uses a pair of frame grabbers in the CAS(Computer Assisted Surgery) system. In this Paper, we developed a synchronized stereo image acquisition method with only one frame grabber Two images from left and right camera each other. were merged with different color space without time delay and thus only one frame grabber was enough toy stereo image. Due to this synchronous Property of image acquisition, we can improve spatial revolution on the computation of 3D Position. Furthermore the overall costs for 3D navigator can be down and the extraction time of stereo Position tan be shortened.

• Journal of Powder Materials
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• v.3 no.3
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• pp.196-200
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• 1996

The dispersion of WC grains Into the interior of an eutectic liquid has been studied by superimposing the eutectic WC-85wt.%Co liquid on the top surface of presintered WC-l0wt.%Co alloy compacts. The heavy WC grains diffused into the interior of liquid from the WC-l0wt.%Co compacts. According to increasing the treating temperatures and times, the dispersion distance from WC-l0wt.%Co substrates increased. The fine WC grains diffused into the liquid faster than the coarse WC grains. The high microstructural stability of WC-Co alloys having the heavier WC grains dispersed in a lighter Co-rich liquid was attributed to Brownian motion of WC grains in liquid. The motion of WC grains in the liquid appears to be same with the colloid(the disperse phase) in a dispersing medium. The dihedral angle of 0 degree of WC-Co at. toy seems one of key parameters, which enables the WC-Co alloys to have high structural stability without settling the WC grains during liquid phase sintering.