• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.195-195
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• 2000

In this paper, intelligent control method using neural network as a nonlinear controller is presented, Neural network controller is implemented on DSP board in PC to make real time computing possible, On-line training algorithm for neural network control is proposed, As a test-bed, a large a-x table was build and interface with PC has been implemented, Experimental results under different PD controller gains show excellent position tracking for circular trajectory compared with those for PD controller only.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.661-665
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• 2000

In this study, the control of mounting system for MLGA package was developed using machine vision for the control of rotating position compensation and mounting position of X-Y table. Two type of material (polymer, alumina )were used for the dielectric insulator of the MLGA. And the illumination system and the algorithm of position compensation that be suitable for these materials was developed. Also, the position control order that compensated by machine vision actuated to micro stepping motor and X-Y servo motor by controlled PC and mounted the MLGA on PCB in resolution to$\pm10\mum$ .

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.492-496
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• 1987

The testing philosophy and control schemes are investigated and applied to construct the Automatic Microwave Leakage Inspection System (AMLIS) . AMLIS is consists of three major parts such as Material Handling Mechanism, Fine Positioning Mechanism and Scanning Mechanism. The material Handling unit is designed to perform loading and unloading microwave oven onto the testing point by pneumatic cylinder and vacuum pump. The Fine positioning part includes X-Y-.THETA. table and distance sensing equipment. The scanning part is composed of five SCARA robots, which traverse X-Y-Z catesian coordinates respectively. The leakage testing probes are placed at the end of this each robot then the path and speed are both controlled via microprocessors. A performance test of this system combined with electric parts and software is done and the basic major function of system are accomplished.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.182-184
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• 2001

Linear pulse Motor(LPM) are used a field where smooth linear motion is required, and it's position accuracy higher than that of a lead. According to the advantage such as simplicity of mechanical frame, high reliability, precise open_loop operation, low inertia etc LPM is applied largely where it have made motor of this kind more and more attractive in many application areas such as factory automation and high speed positioning. This paper is researched to analyze for thrust force characteristic of hybrid LPM. Both the thrust and normal force are very sensitive to the airgap and tooth pitches of the force and platen. To find the optimal design parameter on the hybrid LPM for the embroidery machine. For the field analysis, the finite element method(FEM) is employed for calculating the force. The reluctance models will be used the magnetic permeance of airgap under static-conditions. The forces between forcer and platen have been calculated using the virtual work mathod.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.8
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• pp.623-631
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• 2003

We have fabricated the two-dimensional inverted pendulum system and designed its controller. The two-dimensional inverted pendulum system, which is composed of X-Y table, is actuated through timing belt by each of two geared DC motors. And the control goal is that the rod is always kept to a vertical position to any distrubance and is quickly moved to the desired position. Because this system has generally nonlinear dynamic characteristics and X-axis and Y-axis move together, it is very difficult to find its exact mathematical model and to design its controller. Therefore, we have designed the PID controller with simple structure and excellent performance. Genetic algorithm(GA), which is blown as one of probabilistic searching methods, and human's heuristic control strategy are introduced to design an optimal PID controller. The usefulness of the proposed GA based PID coefficient searching technique is verified through the experiments and computer simulations.

• Korean Journal of Microbiology
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• v.3 no.2
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• pp.1-8
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• 1965

The potato viruses, as possible potato virus X(PVX), potato virus Y(PVY), potato virus S(PVS) are isolated from potato tuber, which collected from eleven areas (Table 1) in Korea. These viruses are isolated by single lesion isolation, Aphid transmission and inoculating methods through the many species of the different plants. The PVX is identified by host range, symptoms, physical properties, serological reaction and electron micrography. The other two viruses are identified by the first two methods mentioned above. The results of the above experiments are as follows. The total value of these viruses infection is 81%. The value of PVX infection is higher than the other two viruses. The properties of PVX are marked as local lesions on Comphrena globosa. The dilution end point is $10^{-6}$, the thermal inactivation point is $70^{\circ}C$ and the size of virus particles is around 13 x 60 $m\mu$.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.6
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• pp.963-971
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• 1990

This paper proposes a memory intensive VLSI architecture for the realization of real-time 3x3 neighborhood processor based on the distributed arithmetic. The proposed architecture is characterized by a bit serial and multi-kernel parallel processing which exploits the pixel kernel parallelism and concurrency. The chip implements 8 neighborhood processing elements in parallel with efficirnt input and output modules which operate concurrently. Besides the a4chitectural design of a neighborhood processor, the design methodology using module generator concept has been considered and MOGOT(MOdule Generator Oriented VLSI design Tool) has been constructed based on the workstation. Based on these design environments MOGOT, it has been shown that the main part of the suggested architecture can be designed efficiently using 2\ulcorner double metal CMOS technology. It includes design of input delay and data conversion module, look-up table for inner product operation, carry save accumulator, output data converter and delay module, and control module.

• Progress in Medical Physics
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• v.28 no.3
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• pp.83-91
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• 2017

In this work, we investigated the recently proposed phase-contrast x-ray imaging (PCXI) technique, the so-called single grid-based PCXI, which has great simplicity and minimal requirements on the setup alignment. It allows for imaging of smaller features and variations in the examined sample than conventional attenuation-based x-ray imaging with lower x-ray dose. We performed a systematic simulation using a simulation platform developed by us to investigate the image characteristics. We also performed a preliminary PCXI experiment using an established a table-top setup to demonstrate the performance of the simulation platform. The system consists of an x-ray tube ($50kV_p$, 5 mAs), a focused-linear grid (200-lines/inch), and a flat-panel detector ($48-{\mu}m$ pixel size). According to our results, the simulated contrast of phase images was much enhanced, compared to that of the absorption images. The scattering length scale estimated for a given simulation condition was about 117 nm. It was very similar, at least qualitatively, to the experimental contrast, which demonstrates the performance of the simulation platform. We also found that the level of the phase gradient of oriented structures strongly depended on the orientation of the structure relative to that of linear grids.

• Journal of the Korea Society of Computer and Information
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• v.17 no.12
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• pp.137-148
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• 2012

In this paper, we proposed the location-aware coordinate routing algorithm for improving the performance of routing algorithm by using ZigBee in Smart Grid environment. A distributed address allocation scheme used an existing algorithm that has wasted in address space. The x, y and z coordinate axes from divided address space of 16 bit to solve this problems. However, coordinate routing does not take account of wireless link condition. If wiress link condition is not considered, when the routing table is updated, the nodes with bad link conditions are updated in the routing table and can be chosen as the next hop. This brings out the retransmissions because of received packet's errors. Also, because of these retransmissions, additional power is consumed. In this paper, we propose the location-aware coordinate routing algorithm considering wiress link condition, where reliable data transmission is made and the consumed enegy is minimize. and we compared and connected region and transition region of ZigBee location based routing in the aspect of average number of multi hops, subordinate packet delivery ratio, delay time, and energy consumption of proposed algorithm. It turned out that there were improvements in performances of each items.

• Journal of The Korean Astronomical Society
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• v.40 no.4
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• pp.99-106
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• 2007

Statistical analyses were performed to investigate the relative success and accuracy of daily maximum X-ray flux (MXF) predictions, using both multilinear regression and autoregressive time-series prediction methods. As input data for this work, we used 14 solar activity parameters recorded over the prior 2 year period (1989-1990) during the solar maximum of cycle 22. We applied the multilinear regression method to the following three groups: all 14 variables (G1), the 2 so-called 'cause' variables (sunspot complexity and sunspot group area) showing the highest correlations with MXF (G2), and the 2 'effect' variables (previous day MXF and the number of flares stronger than C4 class) showing the highest correlations with MXF (G3). For the advanced three days forecast, we applied the autoregressive timeseries method to the MXF data (GT). We compared the statistical results of these groups for 1991 data, using several statistical measures obtained from a $2{\times}2$ contingency table for forecasted versus observed events. As a result, we found that the statistical results of G1 and G3 are nearly the same each other and the 'effect' variables (G3) are more reliable predictors than the 'cause' variables. It is also found that while the statistical results of GT are a little worse than those of G1 for relatively weak flares, they are comparable to each other for strong flares. In general, all statistical measures show good predictions from all groups, provided that the flares are weaker than about M5 class; stronger flares rapidly become difficult to predict well, which is probably due to statistical inaccuracies arising from their rarity. Our statistical results of all flares except for the X-class flares were confirmed by Yates' $X^2$ statistical significance tests, at the 99% confidence level. Based on our model testing, we recommend a practical strategy for solar X-ray flare predictions.