• Journal of KSNVE
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• v.6 no.6
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• pp.851-856
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• 1996

The active noise cancellation system showing the effective convergence and stability has been studied by simplifying the controller structures using the weighting factors of control error path to the multi-channel filtered-x LMS algorithm which needs a lot of calculations and the performance has been verified experimentally. Besides, to implement the system performance in a vehicle cabin, experimental work for selecting the suitable numbers and positions of the microphones and speakers was accomplished. Effectively combining a TMS 320C 31 main processor conducting real number calculations and having various functions with other components, the purpose-built system board for active noise cancellation has been designed and with this board, car active noise cancellation system showing maximum stable 10dB noise reduction has been obtained at the car idling conditions above 3000rpm range.

• 전기의세계
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• v.15 no.4
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• pp.27-38
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• 1966

본 고에서는 앞으로 신설된 배전계통에서의 고저압혼독시 전위상승에 대해 알아보고자 한다. A항의 검토에서 고목계통의 실측치와 D.C. board에 의한 계산치 사이에 약 10-20%의 오차는 있으나 계산치로써 전위상승을 추정할 수 있음을 알았음으로 신설될 23kv Y및 11.4kv Y배전방식에 대하여 계산한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.697-698
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• 2007

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.23-32
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• 2002

The introduction of hybrid and exploitation of heterosis has played a vital role in Indian sericulture industry, which clearly depicts a quantum jump in silk production during the last four decades. Since, the introduction of heterosis, progress in silkworm breeding has depended on success or failure in identifying better combiners. Systematic procedures developed have enabled the breeders to identify the best combiners by combining ability test, line ${\TIMES}$ tester analysis or $D^2$ analysis for maximum expression of heterosis. The level of heterosis expressed in the crossbreed population is determined by the interaction between genotype and prevailing environmental factors. Except some of the pre and post cocoon parameters, heterosis is invariably higher in single crosses compared to three-way and double crosses. However, during hot and humid season, when rearing of F1 bivoltine hybrid is unsuccessful at field level and indigenous races results in very low and poor quality yield, three-way and double crosses can play an important role as an intermediary technology. The objective of this article is to review briefly the concept and causes of heterosis, utilization of different forms of heterosis in silk production and its significance in silkworm, Bombyx mori breeding.

• Journal of Veterinary Clinics
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• v.36 no.6
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• pp.301-305
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• 2019

Wii^® balance board (WBB, Nintendo, Japan) is a device that can measure and record the center of pressure path length (CPPL) and 95% confidence ellipse area (Area 95) in relation to body sway. For evaluating measure of improvement after reconstruction of medial patellar luxation (MPL) in small sized dogs, A total of 6 dogs with limping and lameness gait attributed to Grade II, III or IV MPL were evaluated. Dogs were measured for difference of extension and flexion range of motion in the stifle (dROM), muscle mass, lameness, willingness to bear weight on the affected limb while standing, and willingness to lift the contralateral limb scores, CPPL and Area 95 of WBB on pre-surgery, post-surgery 4, 8 weeks. CPPL was significantly different on pre-surgery compared with post-surgery 8 weeks (p < 0.05). Except for CPPL, measured variables were significantly different on pre-surgery compared with post-surgery 4 and post-surgery 8 weeks (p < 0.01).

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.4
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• pp.198-205
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• 2022

Along with a variety of coding education, physical computing education for controlling various sensors is being actively conducted for elementary, middle, and high school students in line with the era of the fourth industrial revolution. A problem with physical computing education using Arduino is pin connection errors between Arduino and various sensors. Most of the students who come into contact with the Arduino for the first time often do not know the purpose of the Arduino pin and the connection position of the pin. Also, hardware built with incorrect pin connections to the Arduino board often does not work properly. If this case continues, students will lose interest in coding education. Therefore, in this paper, we implemented an augmented reality application that informs the connection process of the Arduino board and the sensor during physical computing coding education using Arduino, and designed and implemented educational content for the Arduino pin position and connection process. First, we explain the role of the Arduino board and the sensor and the location of the pins. After that, the students run the educational augmented reality educational content using their smartphones and check the correct pin connection process between the Arduino and the sensor. In the physical computing education, augmented reality content is used to increase the understanding and immersion of the class. It is expected that the educational effect will also increase by inducing fun and interest in physical computing coding education.

• Journal of Broadcast Engineering
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• v.8 no.4
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• pp.452-464
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• 2003

In this paper, a multi-view 3D video processor was designed and implemented with several FPGAs for real-time applications. The 3D video processor receives 2D images from cameras (up to 16 cameras) and converts then to 3D video format for space-multiplexed 3D display. It can cope with various arrangements of 3D camera systems (or pixel arrays) and resolutions of 3D display. Tn order to verify the functions of 3D video Processor. some evaluation-board were made with five FPGAs.

• Solar Energy
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• v.18 no.3
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• pp.177-183
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• 1998

The thermal performance of a heating board with microencapsualted PCM was investigated and compared to conventional heating board. The employed PCM was the myristic acid $$ and was encapsulated by the multiple layers of PMMA and paraffin wax. The size of encapsulated PCM was $1{\sim}1.5mm$. Accoring to ANSI/ASHRAE test procedure, the close-loop test configuration was installed. Air was used as the heat transfer fluid and a calibrated orifice was employed for the measurement of air flow rates. The thermal performance test of two different heating boards(with 10 wt% PCM and without PCM) was conducted for different air flow rates and the heat transfer characteristics during cooling was compared. The test results showed that the surface temperature of heating board with 10 wt% PCM maintained higher during the cooling process than that of the heating board without PCM and experimentally determined heat transfer coefficient in heating board with PCM showed higher value compared to heating board without PCM.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.7
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• pp.1639-1645
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• 2015

In UHD high-speed video transmission system, when a signal within certain frequency region coincides electrically and structurally, the system becomes unstable because the energy is concentrated, and signal flux is interfered and distorted. For the instability, power integrity analysis should be conducted. To remove the signal distortion for MLB, using a high-frequency design technique for EMI phenomenon, EMI which radiates electromagnetic energy fluxed into power layer was analyzed considering system stabilization. In this paper, we proposed an adaptive MLB design method which minimizes high-frequency noise in MLB structure, enhances signal integrity and power integrity, and suppresses EMI. The characteristic impedance for multi-layer circuit board proposed in this study were High-Speed Video Differential Signaling(HSVDS) line width w = 0.203, line gap d = 0.203, beta layer height h = 0.145, line thickness t = 0.0175, dielectric constant ε_r = 4.3, and characteristic impedance Zdiff = 100.186Ω. When high-speed video differential signal interface board was tested with optimized parameters, the magnitude of Eye diagram output was 672mV, jittering was 6.593ps, transmission frequency was 1.322GHz, signal to noise was 29.62dB showing transmission quality improvement of 10dB compared to previous system.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.7
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• pp.601-606
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• 2016

In this paper, an energy harvester is developed that has advantages regarding piezoelectric noise minimization, mass production, and an easily available environmental energy source, electromagnetic induction, as well as low-frequency bandwidth and high amplitude. A process for fabricating a three-dimensional multilayered planar coil using micro-electro-mechanical systems (MEMS) on a flexible printed circuit board FPCB is introduced. Optimal shape and size were calculated via internal resistance and inductance, and a prototype was fabricated through the MEMS procedure while considering the possibility of mass production. Although the internal resistance matched the designed value, the electromotive force generated did not reach the intended amount. The main reason for the decrease in efficiency was the low area of coil outskirt exposed to the magnetic field while there was relative motion between the magnet and the coil.