• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.3
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• pp.438-444
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• 2015

A new approach to the active phased arrays for the second harmonic generation is presented. Phase variation between the second harmonic oscillators by the mutual synchronization is analyzed theoretically. In this coupling, the active antenna consists of the FET oscillator which plays two roles in fundamental oscillation and frequency multiplying, and the patch antenna resonated at the second harmonic frequency. The radiated second harmonic wave was scanned by varying the free-running oscillation frequencies of the active antennas. In the experiment using the 2-elements array and the 4-elements array, the radiated beam of the second harmonic wave was scanned more widely compared with the case of the fundamental wave radiation.

• The Journal of the Acoustical Society of Korea
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• v.16 no.2
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• pp.16-25
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• 1997

A new method to model the HRTF's(Head-Related Transfer Function), which could give improvement of the sound localization accuracy using the spatial effects by the reflected sound wave transfer characteristics, is proposed. When using the HRTF model having reflected sound wave transfer characteristics, the accuracy of sound localization was quite improved up to about 23%, compared with using the direct wave transfer characteristics only. Furthermore, it is verified that the spatial impression could be a factor to enhance the ability of sound localization.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.141-144
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• 2004

Nowadays, there has been substantial interest in whether there is an association between electromagnetic field exposure and living environment. It is increased the demand that electromagnetic wave environment and its countermeasure. In the present study, we has applied the electromagnetic absorbent inorganic paint of 'I' corporations, and measured electromagnetic waves generated in new apartment before occupancy using the standard field electromagnetic wave generating device we developed. The measurement before occupancy was $100\~131V/m$, but the measurement after occupancy was $6.9\~8.0V/m$ less than 10V/m, the comprehensive electromagnetic wave limit allowed by TCO in Sweden. The implication is that domestic apartment are exposed to extremely poor electromagnetic wave environment. Nevertheless, there have been neither serious efforts to overcome this problem, nor its alternatives and related standards. Therefore, it is necessary to continue research of related fields to establish standards and plans to improve the situation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.8
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• pp.1179-1185
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• 2012

This paper presents a new approach for the detection of seismic events using accumulated changes on time-frequency domain and variable threshold. To detect seismic P-wave arrivals with rapidness and accuracy, it is that the changes on the time and the frequency domains are simultaneously used. Their changes are parameters appropriated to reflect characteristics of earthquakes over moderate magnitude(${\geq}$ magnitude 4.0) and microearthquakes. In addition, adaptively controlled threshold values can prevent false P-wave detections due to low SNR. We tested our method on real earthquakes those have various magnitudes. The proposed algorithm gives a good detection performance and it is also comparable to STA/LTA algorithm in computational complexity. Computer simulation results shows that the proposed algorithm is superior to the conventional popular algorithm (STA/LTA) in the seismic P-wave detection.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1521-1522
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• 2006

Cathode ray tube(CRT)를 대체 할 수 있는 차세대 display 중 plasma display panels(PDPs)가 각광받고 있지만, 여전히 효율 개선은 중요한 과제이다. 본 연구에서는 기존의 PDP driving 중 발광영역에 sine wave를 접목시켜 수치해석하였다. 수치 해석은 2차원 fluid-code simulator를 사용하였고, 여러가지 sine wave형태와 세폭 pulse를 조합하여, 30%이상의 효율 향상을 얻을 수 있었다.

• Bulletin of the Korean Chemical Society
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• v.20 no.4
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• pp.411-416
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• 1999

A new kind of differential flow induced chemical wave is introduced by theoretical calculation. A differential flow between the counter acting species of a dynamical activator-inhibitor system may destabilize its homogeneous reference state and cause the medium to self-organize into a pattern of travelling waves through the differential flow instability (DIFI). In a chemical system, also, the differential bulk flow may change the dynamics of the system, thus it has been refered to as the differential flow induced chemical instability (DIFICI). For DlFICI experiments, one directional flow has been commonly employed, resulting in periodic wave patterns generally. In this study, we considered two directional flow for the DIFICI wave by exchanging artificially the flow direction at some period.

• Structural Engineering and Mechanics
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• v.6 no.3
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• pp.347-362
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• 1998

In this study an improved design method for the traditional A-type(or V-type) offshore template platform system was proposed to mitigate the vibration induced by the marine environmental loadings and the strong ground motions of earthquakes. A newly developed material model was combined into the structural system and then a nonlinear dynamic analysis in the time domain was carried out. The analysis was focused on the displacement and rotation induced by the input wave forces and ground motions, and the mitigation effect for these responses was evaluated when the viscoelastic damping devices were applied. The wave forces exerted on the offshore structures are based on Stokes fifth-order wave theory and Morison equation for small body. A step by step integration method was modified and used in the nonlinear analysis. It was found that the new design approach enhanced with viscoelastic dampers was efficient on the vibration mitigation for the structural system subjected to both the wave motion and the strong ground motion.

• Journal of Contemporary Eastern Asia
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• v.19 no.2
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• pp.179-196
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• 2020

Despite the enormous success in Japan of Korean popular culture, including TV dramas and K-pop, over the past few decades, anti-Korean sentiment in the country has become increasingly visible and intense. In this article, we examine how young Japanese female fans of Korean popular culture engage with the Korean Wave discourse while also engaging with―or, rather, disengaging from―anti-Korean movements and hate speech. Whereas previous scholarship on the Korean Wave has emphasized the power of active fans' agency, this paper investigates how the fans who passionately and self-reflexively consume Korean popular culture understand and react to the growing anti-Korean sentiment in Japan. Through in-depth interviews with 15 of these fans in their 20s and 30s, we show how they have navigated the discursive space between appreciation for Korean culture and anti-Koreanism in Japan.

• Journal of Distribution Science
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• v.22 no.6
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• pp.115-122
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• 2024

Purpose: The main aim of this study is to analyze and suggest new online music distribution models targeted to facilitate the development of the Korean Wave (Hallyu) music market in all locations of the world. This study is conducted through a close analysis of the prevailing distribution models, the unique challenges of the K-pop market, and the trends in new technologies. Research design, data and methodology: To address the issue of how the online music distribution market could be domesticated for the Korean music industry, a systematic review of the previous studies was conducted. The use of the PRISMA approach was followed so that an accurate and transparent method for choosing the studies is ensured. Results: According to the investigation of literature analysis, the online distribution strategy may consist of four key plannings as follows, 1. Leveraging Social Media and User-Generated Content Platforms, 2. Embracing Immersive and Interactive Experiences, 3. Fostering Direct-to-Fan Connections and Monetization, 4. Harnessing Artificial Intelligence and Big Data Analytics. Conclusions: Finally, collaboration and strategic partnerships will be vital. The Korean music companies should seek to cooperate with the technology companies, social media platforms, and the global music streaming services so that they can grow their market, acquire new technologies, and to better their online distribution strategies.

• Journal of the Korean Institute of Telematics and Electronics
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• v.19 no.6
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• pp.17-32
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• 1982

Wave propagation in gyrotropic or anisotropic medium is analyzed in terms of the eigenmodes of the medium, which are admixture of TE and TM waves. The field composition and the phase velocity of the modes are also determined. The results of the analysis are applied to thin film optical waveguide using such medium as substrate and/or film. Based on the characteristic equations for phase constants of the waveguide, the condition for TE-TM mode convection is derived, and wave propagation in the guide is represented in the form of Jones matrix, which allows a new interpretation in the conversion efficiency of the thin-film optical waveguides.