• Journal of Korea Multimedia Society
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• v.19 no.2
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• pp.451-459
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• 2016

The damages on the crops by the wild animals such as wild boars and water deer are serious in rural areas these days. In this paper, a low-cost and adaptive system based on open source for sensing and repelling farm pest animals is proposed. The system contains the server which is Arduino Due connected with the wireless communication modules such as RF, Zigbee, and WiFi module, speaker, and so on. It also has the sensing modules and LED blinkers which communicates with the server by wireless modules. Once a detecting signal is transmitted to the server. The server is waked up from sleep mode and the repelling subsystems such as loud speaker and LED blinker(s) are activated to scare the unwanted animal away. The total system is managed by Android smartphone easily.

• Journal of Astronomy and Space Sciences
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• v.28 no.4
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• pp.267-271
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• 2011

I developed an enhanced correction method for Ricean bias which occurs in linear polarization measurement. Two known methods for Ricean bias correction are reviewed. In low signal-to-noise area, the method based on the mode of the equation gives better representation of the fractional polarization. But a caution should be given that the accurate estimation of noise level, i.e. ${\sigma}$ of the polarized flux, is important. The maximum likelihood method is better choice for high signal-to-noise area. I suggest a hybrid method which uses the mode of the equation at the low signal-to-noise area and takes the maximum likelihood method at the high signal-to-noise area. A modified correction coefficient for the mode solution is proposed. The impact on the depolarization measure analysis is discussed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.3
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• pp.360-366
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• 2018

In shipyards hull forming is performed by the line heating method using a gas torch and by cold treatment using a roll-press. However, this forming process has some issues, such as difficulties in controlling and accurately estimating the amount of the heat input, as well as a harsh working environment due to exposure to loud noises and air pollution. The induction heating method, which is introduced in this paper, exhibits good control and allows for the estimation of precise heat input. Also, workers can carry out the induction heating in a comfortable working environment. In this research, the induction heating simulation, which consists of electro-magnetic, heat transfer and thermal elasto-plastic analysis, was developed and modified through induction heating experiments. Finally, the effective heating coil was designed for the automatic hull forming system based on the results of induction heating simulation. For the purposes of a future study, if an algorithm to obtain optimal working conditions is developed, automatic systems for hull forming can then be constructed.

• Research in Mathematical Education
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• v.19 no.1
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• pp.61-79
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• 2015

This study discussed about how pseudo-thinking process actually occurs in the mind of the students, used Piaget's frame work of the assimilation and accommodation process. The data collection is conducted using Think-Out-Loud (TOL) method. The study reveals that pseudo thinking process of covariational reasoning occurs originally from incomplete assimilation, incomplete accommodation process or both. Based on this, three models of incomplete thinking structure constructions are established: (1) Deviated thinking structure, (2) Incomplete thinking structure on assimilation process, and (3) Incomplete thinking structure on accommodation process.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1288-1292
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• 2007

Mobile phone is necessary articles by increasing mobile communication now. People usually use the Mobile phone in any time and place. Ring tone of Mobile phone effect owner or other person. The sound level of Mobile phone ring tone could be considered as noise if it is too loud a specific situation. Manufacturing company improve ring tone of mobile phone better in consumer's perception. In this study, we record ring tone of mobile phone and estimated the complexity and nonlinear characteristics of the relation between subjective evaluation and sound metrics. Linear regression models were obtained for the subjective evaluation and sound quality metrics. Semantic Differential Method is used to study sound quality Evaluation. To analyze the sound quality of ring tone.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.273-277
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• 2007

In case of the Hydraulic Turbine Dynamo operating for Waterpower Generation, it makes very huge and loud noises, and it influences bad effect physically as same as mentally to those people who are working inside of power plant, and brings the decline of an effective working efficiency. However, its evaluation method or measure about such noise reflects merely its physical attribute which is sensuous Loudness of the Noise itself, since the accumulation effect of Noise or the meaning connected with psychological response did not reflect, it is the actual state that a rational evaluation is unable to expect. Consequently, this Study has attempted to evaluate the Noise of Hydraulic Turbine Dynamo by analyzing the sound quality using Zwicker‘s Psychological Acoustic Parameter, after classification by its positions of the Noise occurring at Hydraulic Turbine Dynamo.

• Korean Journal of Veterinary Research
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• v.55 no.3
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• pp.209-211
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• 2015

An 8-year-old spayed female Maltese (2.5 kg of body weight) presented with the primary complaint of loud heart murmur and exercise intolerance. Diagnostic imaging revealed severe pulmonic stenosis (peak velocity 5.2 m/s) with right ventricular hypertrophy. The dog revisited after 2 years, at which time, diagnostic imaging revealed severe biventricular hypertrophy, dynamic left ventricular outflow tract obstruction, left atrial dilation and pulmonary hypertension with worsened pre-existing pulmonic stenosis. Postmortem investigation revealed hypertrophic cardiomyopathy and regional myocardial infarction. The case was diagnosed as hypertrophic cardiomyopathy secondary to severe right and left ventricular outflow tract obstruction.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.113-115
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• 2003

Recently, many linear motion generators and are rapidly finding applications that ranges from short stroke linear motion vibrators, such as dynamic cone type loud speakers tostirling engine driven linear reciprocatings, alternators, compressors, textile machines etc. In this paper the dynamic performance with load is computed by a general purpose method, which the equation of electromagnetic field, the equation of electric circuit and the equation of motion are coupled together. We fumed out the driving system and the dynamic characteristics of current, voltage and displacement is confirmed experiment.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.415-418
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• 2011

It is critical to assess the characteristics of flame response to pressure perturbations for the understanding of nonlinear combustion instabilities. Previous studies can be grouped into flame response upon perturbed, fresh air and fuel mixture, and flame response directly perturbed from longitudinal waves. The present study presents experimental methodology for the understanding of the flame response exposed to transverse acoustic waves generated by loud speakers.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.121-123
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• 1995

This paper presents a new method which compensates loss of loudness for digital hearing aids. Loudness grows more rapidly in frequency domain with substantial shifts of hearing threshold, so that loud sounds reach the uncomfortable sound level (UCL) at about the same physical stimulus level as with normal hearing. The result is a compression of the available dynamic range of hearing. Many techniques have been developed to compensate for hearing losses. In this paper, we propose a digital hearing aid which uses a single digital filter for reducing distortion and the fuzzy function to calculate gain factors. This function describes how much gain is needed for every frequency to restore loudness perception of a normal ear.