• Journal of Environmental Science International
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• v.18 no.8
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• pp.857-865
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• 2009

The physical properties of an atmospheric boundary layer in Wolryong, a west coastal region of Jeju, South Korea, in terms of the atmospheric stability and roughness length, is important and relevant to both engineers and scientists. The study is aiming to understand the atmospheric stability around this region and its effect on the roughness length. We calculate the Monin-Obukhov length(L) against 3 typical regions of the atmospheric condition - unstable regime (-5$-0.2{\leq}H/L{\leq}0.2$) and stable regime (0.2

• Aerospace Engineering and Technology
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• v.6 no.1
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• pp.114-119
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• 2007

This paper introduces modal test of the 2nd stage structure of KSLV-I which is composed to satellite, PLA(Payload Adapter), EB(Equipment Bay), KMS(Kick Motor Support) and KM(Kick Motor) without PLF(Payload Fairing). In this test, to simulate free-free boundary condition, test object was hung by 4 bungee cords and excited by using impact hammer. From this test, dynamic properties of the 2nd stage structure of KSLV-I can be obtained. Modal test data are analyzed by using TDAS(Test Data Analysis Software). As the result, modal parameters and mode shapes below 100Hz of the 2nd stage of KSLV-I were identified.

• Phonetics and Speech Sciences
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• v.2 no.3
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• pp.47-63
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• 2010

This study provides a description of the glottal characteristics of the word-initial low vowels /a, $\ae$/ in terms of a set of acoustic parameters and discusses glottal configuration as their acoustic correlates. Furthermore, it examines the effect of prosodic boundary on the glottal properties of the vowels, seeking an account of the possible role of prosodic structure based on prosodic theory. Acoustic parameters reported to indicate glottal characteristics were obtained from the measurements made directly from the speech spectrum on recordings of Korean and English collected from 45 speakers. They consist of two separate groups of native Korean and native English speakers, each including both male and female speakers. Based on the three acoustic parameters of open quotient (OQ), first-formant bandwidth (B1), and spectral tilt (ST), comparisons were made between the speech of males and females, between the speech of native Korean and native English speakers, and between Korean and English produced by native Korean speakers. Acoustic analysis of the experimental data indicates that some or all glottal parameters play a crucial role in differentiating the speech groups, despite substantial interspeaker variations. Statistical analysis of the Korean data indicates prosodic strengthening with respect to the acoustic parameters B1 and OQ, suggesting acoustic enhancement in terms of the degree of glottal abduction and the glottal closure during a vibratory cycle.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.931-939
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• 2001

The slot coupling characteristics was analysed in a radial-line slot antenna for its design. The previously proposed waveguide model with a periodic boundary condition on its narrow walls and periodically arranged slots on its wide wall was used. The magnetic field integral equation and two dyadic Green\`s functions for respective regions was derived and the method of moments was used. To maximize the efficiency of numerical analysis and to extract singularities, two different kinds of basis functions, the entire domain basis function and the sub-domain one, are used. In addition, the Ewald sum technique for the rectangular waveguide and the Shanks transform for the half space were used to accelerate the computation of the slowly convergent potential Green\`s functions. Simulation results expressed the effects of the various design parameters on the slot coupling.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.1
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• pp.108-116
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• 1997

A laboratory experiment was made of critical transition flow modes in Czocllralski convection. Numerical computation was also made to delineate the dynamic transition. The period of temperature oscillation ($t_p$) and the interval of temperature oscillation ($\Delta\theta$) were scrutinized to capture the critical transition regime. The mixed convection parameter was varied in the range of $0.134\le Ra/PrRe^2 \le3.804$. The data from calculation were in good agreement with ones from experiment. The influence of the Prandtl number on the transition was examined for Pr ＝ 910, 4445 and 8889. To understand the transition mechanism, the detailed temperature oscillation modes, the isolines of meridional temperature and the axial velocity profiles were investigated.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.4
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• pp.296-308
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• 2001

A fully nonlinear Boussinesq equation of Wei et al. is finite differenced by Adams predictor-corrector method. A spatially distributed source function and sponge layers are used to reduce the reflected waves in the domain and wale breaking mechanism is included in the equation. The generated waves are found to be good and the corresponding wale heights are very close to the target values. The shoaling of solitary wave and transformation of regular wave over submerged shelf were simulated successfully. The characteristics of breaking mechanism was identified through the numerical experiment and the results of two dimensional wave propagation test over the spherical shoal showed the importance of nonlinear wave model.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.12 no.3
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• pp.130-138
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• 2000

The friction factor equation of open channel flow is developed by using Prandtl's mixing length theory and considering the flow characteristics of smooth or rough turbulent flow. BYO model considers vertical velocity profile for the (:omputation of bottom friction of surface waves and current flow. The model computes the mean bottom friction of combined wave-current flow by the vectorial summation of wave velocity and current velocity at Bijker point. The near bottom flow is discriminated by three flow regimes; smooth, transitional and rough turbulent flow. The model, BYO, has been further refined considering the combination of smooth turbulent flow and rough turbulent flow.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.7
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• pp.2326-2336
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• 1996

So most practical combustor is considered to the swirl flame, it is very important to examinate swirl flame structure and combustion characteristics. Recently, attention has been paid to the flame diagnostic by radical luminous intensity. For swirl flame structure and combustion characteristic, reverse flow boundary, temperature, ion current and radical luminous intensity were measured in the double-coaxial swirl combustor which was used principle of multi-annular combustor. This study had three experimental condition, S-type, C-type, SC-type. S-type and C-type flames were formed recirculation zone, but SC-type flame wasn't formed. C-type flame had two recirculation zone. The position with maximum value of ion current and CH-radical, temperature and OH-radical had similarity distribution almost. Therefore, it is possible that the macro structure of flame was measured by radical luminous intensity in the high intensity of turbulent combustion field which was formed by swirl.

• 한국경영정보학회:학술대회논문집
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• 2008.06a
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• pp.590-594
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• 2008

산업의 융합화 추세는 IT서비스 산업이 복잡한 서비스 시스템 통합과 더불어, 제품과 서비스의 융/복합화를 위한 PSS(Product Service System) 구현에 많은 노력을 요구하는 동인으로 작용하고 있다. 이는 제품의 서비스화(product servicize)와 서비스의 제품화(service productize) 현상의 가속화로 인해 제품과 서비스의 구분이 모호해지고 있는 산업변화에 대응하려는 산업의 노력으로 판단된다. 고객 가치 향상을 위해 IT서비스 제조산업(IT Service manufacturing)에서는 제품과 서비스의 모호한 경계를 극복하고, 서비스중심의 신규 IT서비스를 개발할 수 있는 무형의 프로세스 정립이 요구된다. 본 연구에서는 서비스 사이언스 측면에서 제공되는 기법들(PSS, NPD, NSD, UCD, Contingency theory)을 검토하여, IT서비스 제조산업의 특성이 반영된 마케팅 지원 process tool을 개발하는 데에 목적이 있다. 제안된 tool은 목표시장 및 기술환경의 분석과 동시에 IT서비스 제품 분석을 통해 IT서비스 사업 마케팅 기회를 전략적으로 탐색할 수 있는 도구가 될 수 있을 것으로 판단된다.

• The Journal of the Korea Contents Association
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• v.6 no.11
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• pp.45-55
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• 2006

Korean blockbusters are the works finished by the dialectic of the meeting and collision of two cultures or H. Bhabha's cultural hybridization. They represent things Korean and Western, and yet their borders are demolished to create a new complicated mixture. Typical examples are Swiri, JSA Silmido Taegukgi Whinalimyu, containing a special Korean situation of division ideology and expressing an extremely Western style of production. This thesis will study the present status of Korean film aesthetics through the cultural hybridity.