• Title/Summary/Keyword: Outward-Flow

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Water Balance and Flushing Time in the Restricted Indian River Lagoon (IRL), Florida USA

  • Kim, Young-Taeg
    • Ocean and Polar Research
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    • v.25 no.1
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    • pp.75-87
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    • 2003
  • The water balance calculation in the IRL shows that fresh groundwater discharge is the primary factor, with surface runoff from gaged and ungaged areas as the second freshwater contributor. Precipitation and evaporation are almost in balance fer the entire IRL. Due to high freshwater discharge from ground-water, the annual net flow is outward from the IRL to the continental shelf of the Atlantic Ocean resulting in a relatively short flushing time, denoted as $T_{0.5}$ (50% flushing time) and $T_{0.99}$ (99% flushing time). $T_{0.5}$, and. $T_{0.99}$ without a tidal effect in the Northern IRL are 17 and 114 days, respectively, during the dry season. During the wet season, they are 10 and 65 days, respectively. Tidal flushing effects are considered in central IRL due to the proximity to Sebastian Inlet. In the Northern Central zone during dry season, $T_{0.5}$, and. $T_{0.99}$ are 6 and 43 days, respectively and during the wet season 5 and 33 days. In the Southern Central zone they are 2 and 16 days for the dry season,2 and 15 days for the wet season. High groundwater seepage into the IRL is considered to be a positive effect in maintaining relatively good water quality condition even with few narrow inlets.

A Study on Hydraulic Performance of Francis Turbine for Small Hydropower Plants (소수력 발전용 상용 프란시스 수차의 유동해석을 통한 성능 개선에 관한 연구)

  • Choi, Ju-Seok;Kim, Ok-Sam;Kim, Il-Soo;Chun, Chul-Kyun;Moon, Chae-Joo
    • Journal of the Korean Solar Energy Society
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    • v.25 no.3
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    • pp.19-25
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    • 2005
  • Francis turbine of commercial small hydropower plants under 10kw which is investigate a flow characterist and an efficiency in the research which it sees, the problem and an improvement is investigate. In the research which it is simply model with casing, guide-vane, runner, draft tube for simulation numerical analysis of small-sized Francis turbine. Model uses the Gambit and it composes with approximately 800,000 non-uniform lattices. Solutions are investigate the hydraulic characteristics against an outward angle of guide vane, the number of guide vane, head(inlet velocity) by using FLUENT which is a commercial business code.

Passive control of unsteady compression wave using vertical bleed ducts (수직갱을 이용한 터널내 비정상 압축파의 피동제어)

  • Kim, Hui-Dong;Setoguchi, Toshiaki
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.9
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    • pp.1095-1104
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    • 1997
  • When a high-speed railway train enters a tunnel, a compression wave is generated ahead of the train and propagates along the tunnel, compressing and accelerating the rest air in front of the wave. At the exit of the tunnel, an impulsive wave is emitted outward toward the surrounding, which causes a positive impulsive noise like a kind of sonic boom produced by a supersonic aircraft. With the advent of high-speed train, such an impulsive noise can be large enough to cause the noise problem, unless some attempts are made to alleviate its pressure levels. For the purpose of the impulsive noise reduction, the present study investigated the effect of a vertical bleed duct on the compression wave propagating into a model tunnel. Numerical results were obtained using a Piecewise Linear Method and testified by experiment of shock tube with an open end. The results showed that the vertical bleed duct reduces the maximum pressure gradient of compression wave front by about 30 percent, compared with the straight tunnel without the bleed duct. As the width of the vertical bleed duct becomes larger, reduction of the impulsive noise is expected to be greater. However the impulsive noise is independent of the height of the vertical bleed duct.

Numerical Study of Compression Waves Propagating Through Porous Walls (다공벽을 전파하는 압축파에 관한 수치해석적 연구)

  • Kim, Hui-Dong;Setoguchi, Toshiaki
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.11
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    • pp.1403-1412
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    • 1997
  • When a high-speed railway train enters a tunnel, a compression wave is generated ahead of the train and propagates through the tunnel, compressing and accelerating the rest air in front of the wave. At the exit of the tunnel, an impulsive wave is emitted outward toward the surrounding, which causes a positive impulsive noise like a kind of sonic boom produced by a supersonic aircraft. With the advent of high-speed train, such an impulsive noise can be large enough to cause the noise problem, unless some attempts are made to alleviate its pressure levels. In the purpose of the impulsive noise reduction, the present study calculated the effect of porous walls on the compression wave propagating into a model tunnel. Two-dimensional unsteady compressible equations were differenced by using a Piecewise Linear Method. Calculation results show that the cavity/porous wall system is very effective for a compression wave with a large nonlinear effect. The porosity of 30% is most effective for the reduction of the maximum pressure gradient of the compression wave front. The present calculation results are in a good agreement with experimental ones obtained previously.

Language Use in Bongsan Talchum(mask dance) (봉산 탈춤의 언어 사용 연구)

  • 이석규
    • Lingua Humanitatis
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    • v.6
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    • pp.265-291
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    • 2004
  • The main purpose of this paper Is to analyze the characteristics of the Korean language used as a major communication means within the Korean community in Chenguoz District of Harbin, Heirungjiang Province, China, in terms of its phonology, morphology and syntax. The study focuses on how a variety of languages and dialects including Chinese, the Standard Chinese Korean adopted as a means of teaching in Korean schools, and Kyongsang Dialect of Korean have influenced the language of the community. It also deals as background information with the history of the community, the attitude of the community members toward Korean and Chinese, and their proficiencies of Korean and Chinese, to obtain the general picture of the bilingualism of this community. This specific region was studied since this region and most of the Korean communities in the Heirungjiang province were formed by descendents of the immigrants from the southern provinces of the Korean Peninsula, which allows the comparison between the language used today and the language their ancestors used before moving to this area. Due to the industrialization and innovation brought about by the opening of the Chinese society, the fast outward flow of youths to urban areas, and greater assimilation threats from the embedding Chinese culture, we are not too sure if the Korean language will continue to be used in the future. Given these circumstances, we consider this research most opportune in that it provides a look into the Korean community that developed its distinctive culture and language within an isolated cultural environment.

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A Study of Language Use among Korean Residents in China (중국 조선족의 언어사용 양상에 관한 연구 흑룡강성 하얼빈시의 조선족 공동체를 중심으로)

  • 이장송
    • Lingua Humanitatis
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    • v.6
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    • pp.241-263
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    • 2004
  • The main purpose of this paper is to analyze the characteristics of the Korean language used as a major communication means within the Korean community in Chenguoz District of Harbin, Heirungjiang Province, China, in terms of its phonology, morphology and syntax. The study focuses on how a variety of languages and dialects including Chinese, the Standard Chinese Korean adopted as a means of teaching in Korean schools, and Kyongsang Dialect of Korean have influenced the language of the community It also deals as background information with the history of the community, the attitude of the community members toward Korean and Chinese, and their proficiencies of Korean and Chinese, to obtain the general picture of the bilingualism of this community This specific region was studied since this region and most of the Korean communities in the Heirungjiang province were formed by descendents of the immigrants from the southern provinces of the Korean Peninsula, which allows the comparison between the language used today and the language their ancestors used before moving to this area. Due to the industrialization and innovation brought about by the opening of the Chinese society, the fast outward flow of youths to urban areas, and greater assimilation threats from the embedding Chinese culture, we are not too sure if the Korean language will continue to be used in the future. Given these circumstances, we consider this research most opportune in that it provides a look into the Korean community that developed its distinctive culture and tanguage within an isolated cultural environment.

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Experimental study of compression waves propagating porous walls (다공벽을 전파하는 압축파의 실험적 연구)

  • Kim, Hui-Dong;Setoguchi, Toshiaki
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.12
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    • pp.4036-4043
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    • 1996
  • When a high-speed railway train enters a tunnel, a compression wave is generated ahead of the train and propagates along the tunnel, compressing and accelerating the rest air in front of the wave. At the exit of the tunnel, an impulsive wave is emitted outward toward the surrounding, which causes a positive impulsive noise like a kind of sonic boom produced by a supersonic aircraft. With the advent of high-speed train, such an impulsive noise can be large enough to cause the noise problem, unless some attempts are made to alleviate its pressure levels. In the purpose of the impulsive noise reduction, the present study tested the effect of porous walls on the compression wave propagating into a model tunnel. Experimental results were obtained using a shock tube with an open end. The results showed that the cavity/porous wall is very effective for the compression wave with a large nonlinear effect. The porosity of 30% is most effective for attenuation and pressure gradient reduction of the compression wave front. Also the impulsive noise reduction increases with increasing the length and height of the cavity, compared with the tunnel equivalent diameter.

Numerical Analysis of Freezing Phenomena of Water in a U-Type Tube (U자형 배관 내 결빙에 대한 해석적 연구)

  • Park, Yong-Seok;Suh, Jeong-Se
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.12
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    • pp.52-58
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    • 2019
  • This study numerically analyzed the icing process in a U-shaped pipe exposed to the outside by considering the mushy zone of freezing water. Numerical results showed that the flow was pulled outward due to the U-shaped bend in the freezing section exposed to the outside, which resulted in the ice wave formation on the wall of the bended pipe behind. At the same time, the formation of a corrugated ice layer became apparent due to the venturi effect caused by the ice. The factors affecting the freezing were investigated, including the change of the pipe wall temperature, the water inflow velocity, and the pipe bend spacing. It was found that, as a whole, the thickness of the freezing layer increased as the pipe wall temperature decreased. It was also found that the freezing layer became relatively thin when the inflow rate of water was increased, and that the spacing of the pipe bends did not significantly impact the change in the freezing layer.

Demonstration of a Modular Electrostatic Precipitator to Control Particulate Emissions from a Small Municipal Waste Incinerator

  • Intra, Panich;Yawootti, Artit;Tippayawong, Nakorn
    • Journal of Electrical Engineering and Technology
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    • v.9 no.1
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    • pp.239-246
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    • 2014
  • Incineration is conceptually sound as a waste treatment technology. There is, however, concern over its emissions when it is improperly designed and operated. An electrostatic precipitator is one of the most commonly used devices to control particulate emissions from boilers, incinerators and some other industrial processes. In this work, a modular electrostatic precipitator with sizing of $1m{\times}1m{\times}1m$ was developed for removal of particulate matter from the exhaust gases of a small waste incinerator. Its design was based on a simple wire-and-plate concept. The corona discharge wires were connected to a positive high-voltage pulse generator, while the collection plates were grounded. The high-voltage pulse generator was used to produce the corona discharge field between the individual discharge wire and the collection plate. The particulate-laden exhaust gas flow was directed across the corona discharge field. The charged particles were deflected outward and collected on the plate. The collection efficiency was evaluated as a mass loading ratio between the difference at the inlet and the outlet to the particulate loading at the inlet of the precipitator. The collection efficiency of this modular electrostatic precipitator design was approximately 80 %.

Characteristics of contemporary fashion shows affected by intermedia (인터미디어 특성이 나타난 현대 패션쇼 연출 특성)

  • Lee, Seulah;Lee, Yoon Mee;Lee, Younhee
    • The Research Journal of the Costume Culture
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    • v.27 no.6
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    • pp.582-598
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    • 2019
  • Intermedia is a term that refers to the convergence of different media. It has not only enabled the delivery of brand message but also developed interactive communication in a contemporary fashion show context. This study investigates the presentation methods of contemporary fashion shows affected by intermedia. We examined the research and theory related to intermedia and fashion shows by accessing articles since the 2000s concerning 252 shows by 30 designers that tended to demonstrate the use of intermedia. Our analysis highlighted four particular characteristics: "medium scalability" (the unity of art and fashion and the unity of life and fashion); "synesthetic flow" (the audience's emotional immersion, represented by the actual performance and performances of the models); "participatory accessibility" (performance participation through action and instrumental support); and "immaterial symbolization" (an intuitive symbol that emphasizes both the direct outward appearance and the metaphorical symbolism so that the object is expressed in a figurative sense). From these results, we identified considerable synergy between the characteristics of intermedia and contemporary fashion shows. Therefore, it might be useful to conduct an experimental study on this area of research.