• Journal of IKEEE
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• v.5 no.1 s.8
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• pp.43-51
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• 2001

As the density of memories increases, unwanted interference between cells and coupling noise between bit-lines are increased. And testing high-density memories for a high degree of fault coverage can require either a relatively large number of test vectors or a significant amount of additional test circuitry. So far, conventional test algorithms have focused on faults between neighborhood cells, not neighborhood bit-lines. In this paper, a new test algorithm for neighborhood bit-line sensitive faults (NBLSFs) based on the NPSFs(Neighborhood Pattern Sensitive Faults) is proposed. And the proposed algorithm does not require any additional circuit. Instead of the conventional five-cell or nine-cell physical neighborhood layouts to test memory cells, a three-cell layout which is minimum size for NBLSFs detection is used. Furthermore, to consider faults by maximum coupling noise by neighborhood bit-lines, we added refresh operation after write operation in the test procedure(i.e.,$write{\rightarrow}\;refresh{\rightarrow}\;read$). Also, we show that the proposed algorithm can detect stuck-at faults, transition faults, coupling faults, conventional pattern sensitive faults, and neighborhood bit-line sensitive faults.

• Journal of Korea Multimedia Society
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• v.9 no.5
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• pp.542-553
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• 2006

Because Y and C signals in a composite video signal are piled one on another in the same frequency, it is impossible to separate them completely. Therefore, it is necessary to develop efficient separation technique in order to minimize degradation of video quality. In this paper, we propose wavelet-based 3D comb filter algorithm and architecture for separating Y and C signals from a composite video signal. The proposed algorithm uses wavelet transform and thresholding of compared lines for acquiring the maximum video quality. Simulation results show that the proposed algorithm has better image quality and better PSNR than previous algorithms. For real application of the proposed algorithm, we developed a hardware architecture and the architecture was implemented by using VHDL. Finally, a VLSI layout of the proposed architecture was generated by using 0.25 micrometer CMOS process.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.99-109
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• 2010

Existing research about automated wafer transport management strategy for semiconductor manufacturing equipment was mainly focused on dispatching rules which is optimized to specific system layout, process environment or transfer patterns. But these methods can cause problem as like requiring additional rules or changing whole transport management strategy when applied to new type of process or system. In addition, a lack of consideration for interconnectedness of the added rules can cause unexpected deadlock. In this study, in order to improve these problems, propose dynamic priority based transfer job decision making algorithm which is applicable with regardless of system lay out and transfer patterns. Also, extra rule handling part proposed to support special transfer requirement which is available without damage to generality for maintaining a consistent scheduling policies and minimize loss of stability due to expansion and lead to improve productivity at the same time. Simulation environment of Twin-slot type semiconductor equipment was built In order to measure performance and examine validity about proposed wafer scheduling algorithm.

• Journal of Korea Game Society
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• v.11 no.1
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• pp.47-57
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• 2011

Mobile based location-based service can normally be classified into four categories according to their dimensions of their screen layout: map-based, bird-eye view based, photo-based, and video-based. Specifically, video-based layout system combining AR technology has a appealing factor to users through the reality-based presence but normally requires sophisticated real-time image matching algorithms to represent the system. This paper provides a new location-based service by introducing mirror world to resolve the problem and implements its prototype. The proposed service does not need such algorithm and will effectively be useful for users to get the reality of the presence for any locations which is regardless of a user's real location.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2585-2593
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• 2011

Maglev train system has been continuously received attention as it provides good ride quality and low noise and vibration level. Furthermore it is an eco-friendly transport system with little dust pollutant. However the dynamic performance of the vehicle has been influenced by the track layout and the structural stability of guideways and girders, etc. Especially the levitation control of magnetic module is the most important performance of the Maglev system and is very sensitive about the control algorithm and the parameters of the controller. In this paper, the co-simulation of the control and dynamic model has been proposed and the simulation results for the running simulation on the curve track has been shown.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.7
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• pp.1210-1216
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• 2003

Topology optimization is applied to determine the layout of a structural component with a specified frequency by minimizing the difference between the specified structural frequency and a given frequency. The homogenization design method is employed and the topology design problem is solved by the optimality criteria method. The value of a weighting factor in the optimality criteria plays an important role in this topology design problem. The modified optimality criteria method approximated by using the binomial expansion is suggested to determine the suitable value of the weighting factor, which makes convergence stable. If a given frequency is set as an excited frequency, it is possible to avoid resonance by moving away the specified structural frequency from the given frequency. The results of several test problems are compared with previous works and show the validity of the proposed algorithm.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.10
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• pp.806-811
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• 2001

The analysis and control algorithm of a new type unsymmetrical self-bearing step motor is presented. The motor actuator is used for both motor and bearing functionality without any redundant coil windings or redudant electromagnets for bearing functionality. Self bearing step motor layout and control current generation method for unsymmetrical position of electromagnets are described. This new current generation method without additional current for bearing functionality leads to minimize the power loss. As the result of the unbalance response approach, the constant torque is possible, even though the bearing functionality is added or not.

• Proceedings of the Korea Association of Information Systems Conference
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• 1996.11a
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• pp.199-204
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• 1996

It is discussed how to determine the home location of idle vehicles in an AGVS with a loop guide path in a way of maximizing the request-call response probabilities for all demand. Optimal home position is selected by solving the simultaneous equations easily. Static positioning strategy is analyzed in which a single home position is allocated to which every vehicle is routed whenever it becomes idle. The cases of unidirectional guidepath is considered only. We provide a numerical example to illustrate the search algorithm developed for the case and compare the searched optimal solutions with the others.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.35C no.4
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• pp.60-68
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• 1998

In this paper, content addressable momory(CAM) using neural network algorithm is proposed to decrease cell loss and process the large amount of data in streaming mode connectionless server at high speed. To overcome problems of area and power dissipation in look-up table using conventional CAM, the proposed neural network CAM is designed to increase linearly address storage bit about increase of address input bit. Its design and imulation is performed by using VHDL and Compass Tool. Also, its layout is performed by using chip compiler, cell-base P&R tool of compass, in 0.8 .mu.m design rule environment.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.392-397
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• 2001

Topology optimization is applied to determine the layout of a structure whose eigenfrequency coincides with a specified frequency. The topology optimization problem is formulated to minimize the difference between the structural frequency and a given frequency using the homogenization method and the modified optimality criteria method. It turns out that the value of a weighting factor in the updating scheme plays an important role to achieve both a suitable speed and a stable convergence of an algorithm. Unlike a constant weighting factor in previous works, it is suggested that a weight factor is varied during the iteration to control the amount of the frequency change. To substantiate the proposed approach two-dimensional structural design problems are presented and the resulted topology layouts for the specified eigenfrequency are compared to layouts for maximizing the corresponding eigenfrequency.