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SF Movie Star Trek Series and the Motif of Time Travel (SF영화 <스타트랙> 시리즈와 시간여행의 모티프)

  • Noh, Shi-Hun
    • Journal of Popular Narrative
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    • v.25 no.1
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    • pp.165-191
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    • 2019
  • The purpose of this article is to elucidate why the motif of time travel is repeated in the science fiction narrative by examining the functions of this motif in the SF movie series of Star Trek in its narrative and non-narrative aspects. Star Trek IV: The Voyage Home (1986) aims to attract the audience's interest in the story through the use of plausible time travel in the form of the slingshot effect which causes the spacecraft to fly at very fast speeds around an astronomical object. The movie also touches upon the predestination paradox that arises from a change of history in which it describes a formula of transparent aluminum that did not exist at the time. The film also serves as an evocation of the ideology of ecology by including humpback whales in the central narrative and responding to the real issue of the whale protection movement of the times. Star Track VIII: First Contact (1996) intends to interest the audience in the narrative with the warp drive, a virtual device that enables travel at speeds faster than that of light and a signature visual of Star Trek, at the time of its birth through time travel. The film emphasizes the continuation of peaceful efforts by warning the destruction of humanity that nuclear war can bring. It tackles with the view of pacifism and idealism by stressing the importance of cooperation between countries in the real world by making the audience anticipate the creation of the United Federation of Planets through encounters with the extraterrestrial. Star Trek: The Beginning (2009) improves interest through the idea of time travel to the past, this time using a black hole and the parallel universe created thereby. The parallel universe functions as a reboot, allowing a new story to be created on an alternate timeline while maintaining the original storyline. In addition, this film repeats the themes pacifism and idealism shown in the 1996 film through the confrontation between Spock (and the Starfleet) and Nero, the destruction of the Vulcan and the Romulus, and the cooperation of humans and Vulcans. Eventually, time travel in three Star Trek films has the function of maximizing the audience's interest in the story and allowing it to develop freely as a narrative tool. It also functions as an ideal solution for commenting on current problems in the non-narrative aspect. The significance of this paper is to stress the possibility that the motif of time travel in SF narrative will evolve as it continues to repeat in different forms as mentioned above.

The Study and Conservation of Woven Cigarette Inserts (담배 사은품 실크 인서트(Silk Inserts)에 관한 연구와 보존처리)

  • Lee, Young-Joo
    • Journal of the Korean Society of Clothing and Textiles
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    • v.30 no.3 s.151
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    • pp.447-457
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    • 2006
  • The purpose of this study is to document and preserve an unidentified textile purchased at a flea market. This study object is important because it is one of the very rare silk insert series from 1930s which were created for commercial use(as inclusion in cigarette packages). The investigation was conducted by researching the limited publications that discuss silk inserts, visiting many sites on the internet that offer such inserts for sale or catering to the collectors of these silk inserts, and especially visiting the collection of silk inserts, named the J.R. Burdick Collection, at the Metropolitan Museum of Art, New York. Several pieces matched the patches used in the study piece. But Buidick's description on time frame(1912-1915) did not indicate the full range of production of silk inserts. After the identification of object, the conservation treatment was carefully done using adhesives. The results of this study can be summarized as follows; 1. The silk inserts of the study object were included as promotions by some company owned by the American Tobacco Company, probably at some time between 1934 and 1939. 2. The initial stage in the conservation treatment was mechanical surface cleaning using a vacuum cleaner. After vacuuming, humidification was conducted to reduce creases in the top of the object. The damaged areas were backed with stabiltax coated with a solution of Elvace 45675 since the fiber of this object was too deteriorated. 3. Adhesive treatments using Elvace showed satisfactory results: flexibility, strength, no damaging effects on the study object, removability without damaging the object.

An Experimental Study on Filtration Efficiency of Sand Filter Layers to TSS and COD in Non-point Source Pollutant (분산형 빗물 저류조용 모래 여과층을 적용한 도심지 비점오염원의 TSS와 COD 정화효율에 대한 실험적 연구)

  • Ahn, Jaeyoon;Lee, Dongseop;Han, Shinin;Choi, Hangseok
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.5
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    • pp.1477-1488
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    • 2014
  • Prevalent construction of impermeable pavements in urban areas causes diverse water-related environmental issues, such as lowering ground water levels and shortage of water supply for the living. In order to resolve such problems, a rainwater reservoir can be an effective and useful solution. The rainwater reservoir facilitates the hydrologic cycle in urban areas by temporarily retaining precipitation-runoff within a shallow subsurface layer for later use in a dry season. However, in order to use the stored water of precipitation-runoff, non-point source pollutants mostly retained in initial rainfall should be removed before being stored in the reservoir. Therefore, the purification system to filter out the non-point source pollutants is essential for the rainwater reservoir. The conventional soil filtration technology is well known to be able to capture non-point source pollutants in a economical and efficient way. This study adopted a sand filter layer (SFL) as a non-point source pollutant removal system in the rainwater reservoir, and conducted a series of lab-scale chamber tests and field tests to evaluate the pollutant removal efficiency and applicability of SFL. During the laboratory chamber experiments, three types of SFL with the different grain size characteristics were compared in the chamber with a dimension of $20cm{\times}30cm{\times}60cm$. To evaluate performance of the reservoir systems, the concentration of the polluted water in terms of TSS (Total Suspended Solids) and COD (Chemical Oxygen Demand) were measured and compared. In addition, a reduction in hydraulic conductivity of SFL due to pollutant clogging was indirectly estimated. The optimum SFL selected through the laboratory chamber experiments was verified on the in-situ rainwater reservoir for field applicability.

Physical Properties Related to Metamorphic Grade of the Hornfels Exposed Around Mt. Palgong (팔공산 주변 혼펠스의 변성도에 따른 물리적 특성)

  • Shin, Kuk-Jin;Oh, Je-Heon;Jung, Yong-Wook;Kim, Gyo-Won
    • Journal of the Korean Geotechnical Society
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    • v.30 no.5
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    • pp.25-35
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    • 2014
  • The sedimentary rocks exposed around Mt. Palgong were subjected to metamorphism due to a granitic magma intrusion at late Cretaceous, and they eventually metamorphosed to hornfels by the action of both hydrothermal solution and high temperature supplied from the magma. The hornfels zone around the granite body ranges from 2.0 to 3.5 km in width but the boundary between hornfels and sedimentary rocks is not obviously defined because the metamorphic grade gradually decreases with distance from the granite boundary. A series of laboratory tests on 350 core specimens made by 35 fresh rock blocks obtained from 5 selected locations around Mt. Palgong are performed to verify the variation of physical and mechanical properties related to metamorphic grade of the rock. Water content and absorption ratio of the hornfels linearly increase with distance to the granite boundary whereas dry unit weight, p-wave velocity, point load strength, and slake durability index linearly decrease with the distance. These results imply that the metamorphic grade of the hornfels also linearly decrease with the distance to granite boundary. Empirical equations for the variation of properties with the distance to granite boundary and relationship between a property and another one are deduced by regression analyses. And a criteria for classification of hornfels exposed in the study area based on the P-wave velocity and point load strength is proposed.

A study on the estimation of bubble size distribution using an acoustic inversion method (음향 역산법을 이용한 기포의 크기 분포 추정 연구)

  • Park, Cheolsoo;Jeong, So Won;Kim, Gun Do;Moon, Ilsung;Yim, Geuntae
    • The Journal of the Acoustical Society of Korea
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    • v.39 no.3
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    • pp.151-162
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    • 2020
  • This paper presents an acoustic inversion method for estimating the bubble size distribution. The estimation error of the attenuation coefficient represented by a Fredholm integral equation of the first kind is defined as an objective function, and an optimal solution is found by applying the Levenberg-Marquardt (LM) method. In order to validate the effectiveness of the inversion method, numerical simulations using two types of bubble distribution are performed. In addition, a series of experiments are carried out in a water tank (1.0 m × 0.54 m × 0.6 m), using bubbles generated by three different generators. Images of the distributed bubbles are obtained by a high-speed camera, and the insertion losses of the bubble layer are measured using a source and a hydrophone. The image is post-processed to glance a distribution characteristics of each bubble generator. Finally, the size distribution of bubbles is estimated by applying the inversion method to the measured insertion loss. From the inversion results, it was observed that the number of bubbles increases exponentially as the bubble size decreases, and then increases again after the local peak at 70 ㎛ - 120 ㎛.

Study on Perceptions through Big data Analysis on Gambling related News in Korea (한국 사행산업 관련 뉴스의 빅데이터 분석을 통한 인식 연구)

  • Moon, HyeJung;Kim, SungKyung
    • Journal of Broadcast Engineering
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    • v.22 no.4
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    • pp.438-447
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    • 2017
  • The purpose of this study is to understand the recognition of gambling industry through the semantic analysis of news data on lottery, sports betting, horse racing and casino that was reported between 1990 to 2015 in South Korea. This paper revealed the difference between journalists' intention and public's perception about news by analyzing the frequency and connectivity of news with framing and public's interest through semantic network analysis and explored the policy characteristics and innovation task. The result of analysis, news on lottery game mainly has been reported social issue related with win such as 'winning number', 'prize money', 'suspicion of manipulation' and etc. News on sports betting has been reported mandatory information related with business project and illegal site such as 'bidding', 'illegal site', 'sales target' and etc. News about horse racing has been reported the information about the business advertisement such as 'online race track' and 'promotion'. Lastly, casino related news has been reported 'major information' such as illegality', 'gambling place' and 'foreigner'. As a result of times series analysis, news about casino in the 1990s, news about lottery in the 2000s and news about horse racing in 2010s have been increased. Public's interest also has been moved to 'business scandal', 'winning game', 'citizens' campaign' and etc. Gambling related news has been classified by four types, 1. advertising publicity(horse racing), 2. mandatory information(sports betting), 3. social issue(public agenda, lottery), 4. major information(casino). We could get the insight that news can be formed a public agenda, when news is reported as a social issue with high frequency and public's interest like lottery related news.

Simulation-Based Design of Shear Mixer for Improving Mixing Performance (혼합효율 개선을 위한 Shear Mixer의 시뮬레이션 기반 형상 설계)

  • Kim, Tae-Young;Jeon, Gyu-Mok;Ock, Dae-Kyung;Park, Jong-Chun
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.20 no.2
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    • pp.107-116
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    • 2017
  • When drilling operation is being performed, many physical and chemical changes are occurred near wellbore. To handle various changes of well condition and keep drilling process safe, additives of bulk, such as bentonite for increasing density of drilling mud, barite for increasing viscosity of drilling mud, polymer for chemical control, or surfactant, are added into drilling mud through a mud shear mixer. Because the achievement of the required material property through mud mixing system is essential to stabilize drilling system, it is of importance to analyze multi-phase flow during mud mixing process, which is directly related to increase mixing performance of the system and guarantee the safety of the whole drilling system. In this study, a series of liquid-solid flow simulation based on a computational fluid dynamics (CFD) are performed with comparing to solid concentration in experiment by Gilles et al. [2004] to understand the characteristics of liquid-solid mixing in a mud shear mixer. And then, the simulation-based design of shear mixer are carried out to improve mixing performance in a mud handling system.

Field Study for Application of Soil Cementation Method Using Alkaliphilic Microorganism and Low-cost Badge (극한미생물과 저가 배지를 이용한 지반고결제의 현장 적용 연구)

  • Choi, Sun-Gyu;Chae, Kyung-Hyeon;Park, Sung-Sik
    • Journal of the Korean Geotechnical Society
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    • v.31 no.1
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    • pp.37-46
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    • 2015
  • In this study, a blast furnace slag with the alkaliphilic microorganism (Bacillus halodurans) alkaline activator was used to cement natural soils in the field. A low-cost and massive microbial solution for cementation of field soils was produced and compared with existing microbial culture in terms of efficiency. A field soil was prepared for three different cementation areas: a cemented ground with microbial alkaline activator (Microbially-treated soil), a cemented ground with ordinary Portland cement (Cement-treated soil), and untreated ground (Non-treated soil). The testing ground was prepared at a size of 2.6 m in width, 4 m in length, and 0.2 m in depth. After 28 days, a series of unconfined compression tests on the cement-treated and microbially-treated soils were carried out. On the other hand, a torvane test was carried out for non-treated soil. The strength of field soils treated with microorganism was 1/5 times lower than those of cement-treated soil but is 6 times higher than non-treated soil. The pH measured from microbially-treated soil was about 10, which is lower than that of cement-treated soil (pH = 11). Therefore, it is more eco-friendly than Portland cemented soils. The C-S-H hydrates were found in both cement- and microbially-treated soils through SEM-EDS analyses and cement hydrates were also found around soil particles through SEM analysis.

An evaluation of wall functions for RANS computation of turbulent flows (난류 흐름의 RANS 수치모의를 위한 벽함수 성능 평가)

  • Yoo, Donggeun;Paik, Joongcheol
    • Journal of Korea Water Resources Association
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    • v.53 no.1
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    • pp.1-13
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    • 2020
  • The most common approach for computing engineering flow problems at high Reynolds number is still the Reynolds-averaged Navier-Stokes (RANS) computations based on turbulence models with wall functions. The recently developed generalized wall functions blending between the wall-limiting viscous and the outer logarithmic relations ensure a smooth transition of flow quantities across two regions. The performances and convergence properties of widely used turbulence models with wall functions that are applicable for turbulence kinetic energy (TKE), turbulent and specific dissipation rates, and eddy viscosity are presented through a series of near wall flow simulations. The present results show that RNG k-𝜖 model should be carefully applied with small tolerance to get the stable solution when the first grid lies in the buffer layer. The standard k-𝜖 and RNG k-𝜖 models are not sensitive to the selection of wall functions for both TKE and eddy viscosity, while the k-ω SST model should be applied together with kL-wall function for TKE and nutUB-wall functions for eddy viscosity to ensure accurate and stable boundary conditions. The applications to a backward-facing step flow at Re=155,000 reveal that the reattachment length is reasonably well predicted on appropriately refined mesh by all turbulence models, except the standard k-𝜖 model which about 13% underestimates the reattachment length regardless of the grid refinement.

Effect of Stress Induced Phase Transformation on $Al_2 O_3$ Matrix Dispersed with $ZrO_2-Y_2O_3$ ($Y_2O_3-ZrO_2$$Al_2 O_3$ 매트릭스에 분산시 응력 유기 상변태의 효과)

  • Lee, Tae-Keun;Lim, Eung-Keuk;Kim, Hwan
    • Journal of the Korean Ceramic Society
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    • v.22 no.1
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    • pp.11-18
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    • 1985
  • The effect of stress induced phase transformation on $Al_2 O_3$ matrix dispersed with $ZrO_2-Y_2O_3$ has been studied. In order to determinate the mechanical properties three $Al_2O_3-ZrO_2$ composite series containing 1, 3 and 5 mole% $Y_2O_3$ were prepared. The starting materials were $Al_2O_3$ and $ZrO_2-Y_2O_3$ which was prepared from the aqueous solution of high purity $YCl_3$.$6H_2O$ and $ZrOCl_2$.$8H_2O$. Powder mixtures of $Al_2O_3-ZrO_2$ containing $Y_2O_3$ have been prepared by ball-milling with methanol and the samples were formed by isostatic press and sintered at 150$0^{\circ}C$ for 2hrs. After sintering. the specimens were polished for mechanical determination. The relative density of sintered specimens were also measured. It was found that the addition of 1, 3mole% to {{{{ { ZrO}_{2 } }} allowed full retention of the tetragonal phase in $Al_2O_3-ZrO_2$ but partially stabilized zirconia (PSZ) was produced by additions of 5 mole% $Y_2O_3$.The critical stress-intensity factor KIc of $A_2O_3-ZrO_2$ (containing 1 mole% $Y_2O_3$) composite materials increased with increasing $ZrO_2$ content, The maximum value of KIC=7Mn/$m^3$/2 at 20 mole% $ZrO_2$ exhibited about twice that of the $Al_2 O_3$ The modulus of rupture exhibited a trend similiar to KIC The maximum value of MOR was 580MN/m2. As the amount of Y2O3 increase it was observed that the maximum of KIC and MOR decreased : Additions of 3 mole% $Al_2O_3$ $Y_2O_3$ allowed the maximum of KIC 6MN/$m^3$/2 MOR 540MN/$m^2$ at 15 mole% $ZrO_2$ additions of 5 mole% $Y_2O_3$ allowed the maximum of KIC 5MN/$m^3$/2 MOR 410MN/$m^2$ at 10 mole% $ZrO_2$.

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