• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.9
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• pp.1739-1747
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• 1994

This study is concerned with a feeding method of microstrip patch antennas with different widths as feeding elements in order to obtain the appropriate radiation patterns of nonuniform array antennas. We analyze a microstrip patch antenna based on the transmission line model and derive that the ratio of current is equal to that of the input impedances of array antenna elements in case that the feed-line length between elements of array antenna is equal to the integer times of $\lambda_g$. We measure the radiation patterns of the nonuniform microstrip patch array antenna with 6 and 9 elements. The patterns measured are well agreed with the theoritically calculated patterns. Thus, this result can be utilized in the implementation of a feed network in nonuniform array antennas.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.6
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• pp.636-636
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• 1997

This paper presents the design and fabrication of a shaped-beam array antenna which will be used for a PCS basestation using structure that is coupled to a microstrip line by an aperture on the intervening ground plane. The shaped-beam pattern is obtained by an antenna synthesis method. An array antenna considering the mutual coupling between array elements(patches) and a feeding network are designed by CAD tools. The feeding network is designed by using the Wilkinson power divider to obtain the optimized shaped-beam. The designed results are compared with the measured data.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.2
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• pp.228-235
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• 2011

In this paper, we propose a $4{\times}8$ SIW(Substrate Integrated Waveguide) slot array antenna for dual-polarized phased array system. The basic part of the array is a subarray comprising an vertical-polarization and horizontal-polarization. A vertical-polarization slotted SIW single-polarization linear array. Using SIW, A vertical polarization linear array consists of 8 uniform longitudinal slots and 4-way SIW feeding network. Using HMSIW, horizontal-polarization linear array consists of 8 slots and 4-way SIW feeding network.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.595-598
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• 2006

In this letter, a compact rectangular spiral antenna is proposed. Instead of a center excitation of conventional spiral antennas, the proposed antenna is adopted a modified feed network, feeding at the end of the spiral. The matching circuit of $'{\sqsupset}'$ shape is added at the feeding point. With this matching circuit, we can easily match the input impedance well, without the limit of the space. The parameter which determines the circular wave characteristic is explained, and the design guideline of the proposed antenna is presented. We design a proposed antenna operating at 9.5 GHz. Its size is only $0.6\lambda_g\times0.6\lambda_g$. The simulated bandwidth of the input impedance $(S11\leq-10)$ is 8.12% and that of $(AR\leq-3)$ is 4.62%, which is excellent characteristics as compared to its simple structure.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.12
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• pp.84-91
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• 2004

A CCD camera with a laser stripe was applied to realize the automatic weld seam tracking in GMAW. It takes relatively long time to process image on-line control using the basic Hough transformation, but it has a tendency of robustness over the noises such as spatter and arc tight. For this reason, it was complemented with adaptive Hough transformation to have an on-line processing ability for scanning specific weld points. The adaptive Hough transformation was used to extract laser stripes and to obtain specific weld points. The 3-dimensional information obtained from the vision system made it possible to generate the weld torch path and to obtain the information such as width and depth of weld line. In this study, a neural network based on the generalized delta rule algorithm was adapted for the process control of GMA, such as welding speed, arc voltage and wire feeding speed.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.275-280
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• 1990

A neural network method is applied for recognizing the orientation o f individual parts being fed from a bowl feeder. The system is designed in such a way that a part can be discriminated and sorting according to every possible stable orientation without implementing any a mechanical tooling. The operation of the bowl feeder is based on a 2D image obtained from an array of fiber optic sensor located on the feeder track. The acquired binary image of a moving and vibrating part is used as input to a neural network which, in turn, determines t he orientation of the part. The main task of the neural network, here is to synthesize the appropriate internal discriminant functions for the part orientation using the part features. A series of the experiments reveals several promising points on performance. Since the operation of the feeder is highly programmable, it is well suited for feeding and sorting small parts prior to small batch assembly work.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.3
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• pp.99-106
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• 2002

This study presents an approach to model the Electric Railway System with the common grounding based on the 8-port network model and to analyse traction power feeding system focused on the amplification of harmonic current. The entire system can be easily modeled by the combination of 8-port representation of each component in parallel and/or series. Through the research, 8-port network model which can be effectively applied to harmonic analysis is derived.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.2
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• pp.251-258
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• 2023

In this paper, we propose DLP(Dual Linear Polarization) stack antenna for private network. The proposed antenna has general stack structure and design airgap between two substrate to obtain the maximum gain. Also, to improve cross polarization isolation, two feeding port is designed to separate for each substrate. The size of each patch antenna is 17.80 mm(W1)×16.70 mm(L1) for lower patch and 18.56 mm(W2)×18.73 mm(L2) for upper patch, which is designed on the FR-4 substrate which thickness (h) is 1.6 mm, and the dielectric constant is 4.3, and which is 40.0 mm(W)×40.0 mm(L) for total size of substrate. From the fabrication and measurement results, bandwidths of 100 MHz (4.74 to 4.84 GHz) for feeding port 1, and 150 MHz (4.67 to 4.82 GHz) for feeding port 2 are obtained on the basis of -10 dB return loss and transmission coefficient S21 is got under the -20 dB. Also, cross polarization isolation between each feeding port obtained

• Journal of Animal Environmental Science
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• v.8 no.3
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• pp.199-208
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• 2002

This paper introduces the method to make management network about milking cow farm tasks. The object of this research was to design of biological measuring system and managing network system in a livestock farm. This auto-management system provides informations about individual cows' temperature, conductivity of milk and weight for efficient management of feeding, and milking works by a micro-processor and RS -485 type serial COM. ports. And measured bio-data which are basic informations for remote raising management are saved to user PC by serial communication between the PLC and user PC. Milking cow farm is divided into three working place to each measurement work and feed. The first working place is milking station which has two thermometers, a conduct meter and a scale set. The second working place is feeding station, and the third place is cattle cage. These are combined by network system and the PLC which is used to drive network and sub-modules. Sub-modules have a micro-process to control the sensor and to interface with network. The PLC which drive network and control sequence has two serial communication port to be linked with user PC for sending the measured data and for receiving data. Above all, in this study tells the sequence operating method by the driving scenario of breeding milk cow for livestock auto-management using the PLC and network system.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.516-522
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• 2014

This study was conducted to investigate the impact of the anthropogenic factors affecting distribution of the Red-crowned Crane and White-naped Crane wintering in Cheorwon, Korea. Especially, it was investigated that the impact power and its range of the anthropogenic effect to the feeding flock density in cranes due to the paved road, residential area, military facilities and greenhouse density. The Red-crowned Crane and the White-naped Crane showed the similar preference and sensitivity against anthropogenic factors, because correlation of feeding flock density of the Red-crowned Crane and White-naped Crane was similar in the same site. The feeding flock density of the cranes near the residential area was lower than that of area far from the area, and tended to increase within 2.5 km distance. The increasing tendencies of feeding flock density from military facilities and high traffic volume road were similar, but the density in military facilities increased within 0.8 km, and the density from high traffic volume road increased within 2 km. This results suggested that military facilities and the road with high traffic volume made significant influence on foraging densities to the certain range. As the distance from the road with low traffic volume increased, feeding flock density tended to decrease. The area near the low traffic volume road had high feeding flock density because remaining rice grains were preserved by intermittent disturbances in that area. If the density of greenhouse is lower than $40/km^2$, feeding flock density in the low greenhouses density area was higher than high greenhouses density area. However, there was no difference in the feeding flock density if the density of the green houses is higher than $40/km^2$.