• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.533-544
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• 2020

In this paper, we conducted a dynamic ex-post assessment on the grape business cessation support System. Based on the analysis results, in the short term, there was an increase in grape price due to a decrease in production and accompanying increases in the prices of consumption substitution items. However, in the long run, grape prices fell again due to an increase in grape production because of the entry of new grape farmers and the growth of adult grape trees. In addition, the analysis showed that the balloon effect caused by the conversion of crops caused indirect damage such as an increase in the production volume of substitution crops and a decrease in prices. When analyzing the social welfare measurement, the results showed that the support system for business cessation increased the overall social welfare due to an increase in producer welfare because of a price increase in the short term, but in the long term, both producer and consumer welfare decreased. In the end, it is necessary to review the system because the government's intervention may cause market distortion and inefficient resource allocation. Above all, it is necessary to minimize the indirect effect of the industry's contraction and balloon effect due to excessive business cessation. For this, conditional support should be provided in parallel with post management rather than unconditional support. In addition, it is necessary to provide a strategic support system that considers substitution items in addition to those items to be supported.

• Journal of the Korean Magnetics Society
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• v.15 no.6
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• pp.307-310
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• 2005

To get the spatial feature of arterial pulse, we designed spatial pulse diagnostic apparatus (SPDA) using a 2-dimensional magnetoresistive sensor array. The magnetic field distribution fur magnet may was simulated using finite element method. We recognized that the field distribution of parallel magnet mays was more sensitive and uniformed than that of perpendicular one. Also the spatial displacements of magnet array were agreed with the output signal of magnetic tunnel junction (MTJ) sensor array.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.1C
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• pp.45-54
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• 2010

This paper studies the design of a multiuser multiple-input multiple-output (MIMO) system, where a base station (BS) transmits independent messages to multiple users. The remarkable "dirty paper coding (DPC)" result was first presented by Costa that the capacity does not change if the Gaussian interference is known at the transmitter noncausally. While several implementable DPC schemes have been proposed recently for single-user dirty-paper channels, DPC is still difficult to implement directly in practical multiuser MIMO channels. In this paper, we propose a network channel matrix triangulation (NMT) algorithm for utilizing interference known at the transmitter. The NMT algorithm decomposes a multiuser MIMO channel into a set of parallel, single-input single-output dirty-paper subchannels and then successively employs the DPC to each subchannel. This approach allows us to extend practical single-user DPC techniques to multiuser MIMO downlink cases. We present the sum rate analysis for the proposed scheme. Simulation results show that the proposed schemes approach the sum rate capacity of the multiuser MIMO downlink at moderate signal-to-noise ratio (SNR) values.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.2
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• pp.83-92
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• 2018

Using ground moving target indicators equipped with synthetic aperture radars for locating moving targets within a wide background clutter in a short time is an excellent method for monitoring traffic. Although the displaced phase center antenna (DPCA) technique and along track interferometry (ATI) are real time methods with low computational complexity, they are essential for reducing cases of false alarm that can result in poor performance. In this paper, we propose two detection methods using DPCA and ATI-the parallel fusion method and serial fusion method. Simulation results demonstrate that the proposed detection methods are characterized by low probability of false alarm along with good performance. In particular, the serial fusion method possesses high detection probability along with low probability of false alarm (1/5th of the false alarm probability of the DPCA technique).

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.8
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• pp.1854-1863
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• 2003

In the recent digital communication systems, the performance of Turbo Code using the mr correction coding depends on the interleaver influencing the free distance determination and the recursive decoding algorithms that is executed in the huh decoder. However, performance depends on the interleaver depth that needs many delays over the reception process. Moreover, turbo code has been blown as the robust coding methods with the confidence over the fading channel. International Telecommunication Union(ITU) has recently adopted it as the standardization of the channel coding over the third generation mobile communications(IMT­2000). Therefore, in this paper, we preposed the interleaver that has the better performance than existing block interleaver, and modified turbo decoder that has the parallel concatenated structure using MAP algorithm. In the real­time voice and video service over third generation mobile communications, the performance of the proposed two methods was analyzed and compared with the existing methods by computer simulation in terms of reduced decoding delay using the variable decoding method over AWGN and fading channels for CDMA environments.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.2
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• pp.265-276
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• 2017

In this paper, a robust and more accurate trajectory tracking control method for a mobile robot is proposed using WIPDC(Weighted Integral Parallel Distributed Compensation) and T-S Fuzzy disturbance observer. WIPDC reduces the steady state error by adding weighted integral term to PDC. And, T-S Fuzzy disturbance observer makes it possible to estimate and cancel disturbances for a T-S fuzzy model system. As a result, the trajectory tracking controller based on T-S Fuzzy disturbance observer shows robust tracking performance. When the initial postures of a mobile robot and the reference trajectory are different, the initial control inputs to the mobile robot become too large to apply them practically. In this study, also, the problem is solved by designing an initial approach path using a path planning method which employs $B\acute{e}zier$ curve with acceleration limits. Performances of the proposed method are proved from the simulation results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.9A
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• pp.917-923
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• 2008

The D-STTD system obtains the diversity gain through the STTD scheme and the Multiplexing gain through parallel structure of the encoder using the STTD scheme known Alamouti Code. We are difficult to use Combining scheme of the STTD scheme for the D-STTD detection in the decoder because the D-STTD system transmits mutually different data in each other STTD encoder for multiplexing gain. Therefore, in this paper we combine the D-STTD system with Linear algorithm, SIC algorithm and OSIC algorithm known multiplexing detection scheme based on MMSE scheme and compare the performance of each system. And we propose the detection scheme of the D-STTD using MAP Algorithm and analyze the performance of each system. The simulation results show that the detector using iterative algorithm has better performance than Linear MMSE Detector. Especially, we show that the detector using MAP algorithm outperforms conventional detector.

• Journal of Power Electronics
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• v.16 no.1
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• pp.297-309
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• 2016

Grid-connected inverters (GCIs) with an LCL output filter have the ability of attenuating high-frequency (HF) switching ripples. However, by using only grid-current control, the system is prone to resonances if it is not properly damped, and the current distortion is amplified significantly under highly distorted grid conditions. This paper proposes a synchronous reference frame equivalent proportional-integral (SRF-EPI) controller in the αβ stationary frame using the parallel virtual resistance-based active damping (PVR-AD) strategy for grid-interfaced distributed generation (DG) systems to suppress LCL resonance. Although both a proportional-resonant (PR) controller in the αβ stationary frame and a PI controller in the dq synchronous frame achieve zero steady-state error, the amplitude- and phase-frequency characteristics differ greatly from each other except for the reference tracking at the fundamental frequency. Therefore, an accurate SRF-EPI controller in the αβ stationary frame is established to achieve precise tracking accuracy. Moreover, the robustness, the harmonic rejection capability, and the influence of the control delay are investigated by the Nyquist stability criterion when the PVR-based AD method is adopted. Furthermore, grid voltage feed-forward and multiple PR controllers are integrated into the current loop to mitigate the current distortion introduced by the grid background distortion. In addition, the parameters design guidelines are presented to show the effectiveness of the proposed strategy. Finally, simulation and experimental results are provided to validate the feasibility of the proposed control approach.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2000.12a
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• pp.13-16
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• 2000

In the recent mobile communication systems, the performance of Turbo Code using the error correction coding depends on the interleaver influencing the free distance determination and the recursive decoding algorithms that is executed in the turbo decoder. However, performance depends on the interleaver depth that need great many delay over the reception process. Moreover, Turbo Code has been known as the robust coding methods with the confidence over the fading channel. The International Telecommunication Union(ITU) has recently adopted as the standardization of the channel coding over the third generation mobile communications the same as IMT-2000. Therefore, in this paper, we proposed of that has the better performance than existing Turbo Decoder that has the parallel concatenated four-step structure using MAP algorithm. In the real-time voice and video service over the third generation mobile communications, the performance of the proposed method was analyzed by the reduced decoding delay using the variable decoding method by computer simulation over AWGN and lading channels.

• The KIPS Transactions:PartA
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• v.15A no.4
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• pp.189-198
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• 2008

In this paper, we prove mesh-like networks can be embedded into Petersen-Torus(PT) networks. Once interconnection network G is embedded in H, the parallel algorithm designed in Gcan be applied to interconnection network H. The torus is embedded into PT with dilation 5, link congestion 5 and expansion 1 using one-to-one embedding. The honeycomb mesh is embedded into PT with dilation 5, link congestion 2 and expansion 5/3 using one-to-one embedding. Additional, We derive average dilation. The embedding algorithm could be available in both wormhole routing system and store-and-forward routing system by embedding the generally known Torus and honeycomb mesh networks into PT at 5 or less of dilation and congestion, and the processor throughput could be minimized at simulation through one-to-one.