• Resources Recycling
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• v.20 no.4
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• pp.58-64
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• 2011

Recovery of novel metals such as Au, Ag and Ni from wastes PCB was investigated by slag treatments. The CaO-$Al_2O_3$(-$SiO_2$) and CaO-$SiO_2$-$CaF_2$ slags were employed in the present study. The PCB/Cu ratio is recommended to be lower than unity. The use of CaO-$SiO_2$-$CaF_2$ slag provided the more higher yield of Au, Ag and Ni than the CaO-$Al_2O_3$(-$SiO_2$) slag did, which was mainly due to the lower melting point and the viscosity of $CaF_2$-containing slag. The terminal descending velocity of metal droplets in the slag phase increased with decreasing slag viscosity.

• Journal of IKEEE
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• v.23 no.3
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• pp.873-877
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• 2019

In this paper, we analyze the degree of digital noise coupling for Inverted F Antenna (IFA) and Loop Antenna, which are representative types of portable terminal antenna, using characteristic mode. Firstly, the degree of coupling according to the direction of digital signal lines and characteristic mode current of the printed circuit board (PCB) including the antenna is compared and analyzed, and based on this result, the coupling between WiFi antenna and the front camera noise is analyzed. For analysis, the digital signal line and ground line of the FPCB of the camera module are modeled as a loop feeder that excites the characteristic mode of the PCB ground and the change of noise coupling according to the antenna types are analyzed.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.6
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• pp.664-670
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• 2018

In modern society, CCTV, which is the eye of surveillance, is being used to collect image data in various ways in daily life. CCTV is used not only for security, surveillance, and crime prevention but also in many fields such as automobile and black box. In this paper, we have developed a STM32F407 ARM chip based camera system for various applications. In order to develop camera system, modeling of camera system based on 3D structure was carried out in SolidWorks environment. The PCB board design was developed to extract the PCB parts from the camera system modeling files into iges files, convert them from the Altium Designer tool into 3D and 2D boards, After designing the camera system circuit and PCB, we have been studying the implementation of the stable system by using TRM (Thermal Risk Management) tool to cope with the heat simulation generated on the board.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.2
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• pp.135-140
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• 2008

In this paper, the spiral antenna with the center frequencies of 315MHz, 433MHz, and 447MHz for RKE system of a vehicle is designed on PCB. The antenna is microstrip line-fed, and applied PIFA concept near the feeding part to easily tune center frequency and input impedance. The PIFA-type spiral antenna with the size of $30mm{\times}20mm$ is designed on printed PCB by considering the effect of circuits and components on PCB, ECU case and vehicle body. Also chip inductor inserted dual-band spiral antenna of 315MHz and 447MHz is designed. We found that the antenna designed on PCB satisfied the antenna specifications through measurement and field test.

• Journal of Broadcast Engineering
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• v.26 no.4
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• pp.409-418
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• 2021

Conformal coating is a technology that protects PCB(Printed Circuit Board) and minimizes PCB failures. Since the defects in the coating are linked to failure of the PCB, the coating surface is examined for air bubbles to satisfy the successful conditions of the conformal coating. In this paper, we propose an algorithm for detecting problematic bubbles in high-risk groups by applying image signal processing. The algorithm consists of finding candidates for problematic bubbles and verifying candidates. Bubbles do not appear in visible light images, but can be visually distinguished from UV(Ultra Violet) light sources. In particular the center of the problematic bubble is dark in brightness and the border is high in brightness. In the paper, these brightness characteristics are called valley and mountain features, and the areas where both characteristics appear at the same time are candidates for problematic bubbles. However, it is necessary to verify candidates because there may be candidates who are not bubbles. In the candidate verification phase, we used convolutional neural network models, and ResNet performed best compared to other models. The algorithms presented in this paper showed the performance of precision 0.805, recall 0.763, and f1-score 0.767, and these results show sufficient potential for bubble test automation.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.12
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• pp.97-102
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• 2011

We propose a novel displacement measurement method in the LVDT (Linear Variable Differential Transformer) structure. This proposed algorithm is independent of coil pattern, which may be implemented to PCB, or transformer component, because it is based on the signal-mapping method. we have manufactured several boards which have different coil patterns and our algorithm is ported into TMS320F2812 of TI DSP chipset. The output signal has high accuracy and high stability although PCB coil pattern are coarse.

• Animal Bioscience
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• v.34 no.2
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• pp.233-242
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• 2021

Objective: The aim of this study was to determine the effect of pineapple cannery by-product (PCB) level on the growth performance and carcass characteristics of finishing Hanwoo steers. Methods: The feeding stage was divided into early and late finishing stages. A total of 60 castrated Hanwoo steers (13.9±0.8 months old, 418.8±36.5 kg initial body weight [BW]) were blocked by initial BW and then randomly allotted into 12 pens (five head/pen). The pens were randomly assigned to control (CONT), low PCB (LPCB), or high PCB (HPCB) treatments. These diets contained 0%, 1.5%, or 3.0% of PCB (on a dry matter [DM] basis; as-fed basis was 0%, 10.6%, or 21.2%), respectively. Results: For the early finishing stage, body weight gain (BWG) and average daily gain (ADG) of the CONT and LPCB feeding groups were greater (p<0.05) than those of the HPCB feeding group. In addition, there were linear and quadratic effects on BWG and ADG with increasing dietary PCB level (p<0.05). The gain to feed (G:F) ratio tends to quadratically decrease with an increasing PCB level in the early finishing stage (p = 0.076). Growth performances of late finishing stage were not affected by PCB level. The marbling score of the LPCB feeding group was similar to that of the CONT feeding group. However, there was a linear decrease (p< 0.05) in marbling score and quality grade among treatments as PCB was increased in the diet. In the longissimus muscle free amino acid profile, histidine composition increased linearly (p<0.05) with an increasing level of PCB. Conclusion: The level of PCB 1.5% DM in diet can be used for finishing steers without any adverse effects on growth and carcass performances. However, there were some negative effects on growth and carcass performance in the HPCB feeding group.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.521-527
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• 2011

POWER PC series are common to the Central Processing Unit for Military Single Board Computer. Among them, G4 group, which contains the 74xx series supported by Freescale manufacturer is mainly used in the Military applications. We focus on the Interface between memory and controller. PCB stacking method, component routing, impedance matching and harsh environment for Military spec are the main constraints for implementation. Also, we developed memory as a module for the consideration of Military environments. The overall type of SBC should be designed by the form of 6U VME or 3U VME. Therefore this study suggests the electrically optimum Interface matching, Artwork technology based on the signal cross over and PCB stacking method on the harsh environment.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.4
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• pp.119-125
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• 2007

In this paper, a miniaturized PCB-integrated antenna is proposed for bluetooth applications. The proposed antenna is a modified form of the printed inverted F antenna where the size reduction is achieved by employing the meander strip for the resonant length part of the radiator. The antenna dimension is optimized using the commercial electromagnetic software MWSTM. The designed antenna is fabricated by the standard photo-etching technique and its performance is measured. The fabricated antenna shows a bandwidth of 125MHz centered at 2.45GHz and a gail of -0.23dBi. The size of the proposed antenna is $9.65mm{\times}5.95mm$ corresponding to the 55 percent of the area of the existing printed inverted F antenna.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.1
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• pp.39-45
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• 2008

In this parer a branch type inverted-F structure antenna with dual-band is proposed. The proposed antenna has a size of about $70mm{\times}35mm{\times}0.8mm$ with a total mobile phone PCB for support and patch of about $12mm{\times}8mm{\times}0.8mm$. This antenna is designed to operate of frequency 2.45GHz and 5.8GHz, Bandwidth at each other frequency is satisfied $83MHz{\sim}100MHz$ in frequencies. Also, The designed and fabricated dual-band antenna for 2.45GHz, 5.8GHz have a gain between 2.0dBi and -1.0dBi at all bands.