• Title/Summary/Keyword: 소멸가능성

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Development of Adsorbent for Vapor Phase Elemental Mercury and Study of Adsorption Characteristics (증기상 원소수은의 흡착제 개발 및 흡착특성 연구)

  • Cho, Namjun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.5
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    • pp.1-6
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    • 2021
  • Mercury, once released, is not destroyed but accumulates and circulates in the natural environment, causing serious harm to ecosystems and human health. In the United States, sulfur-impregnated activated carbon is being considered for the removal of vapor mercury from the flue gas of coal-fired power plants, which accounts for about 32 % of the anthropogenic emissions of mercury. In this study, a high-efficiency porous mercury adsorption material was developed to reduce the mercury vapor in the exhaust gas of coal combustion facilities, and the mercury adsorption characteristics of the material were investigated. As a result of the investigation of the vapor mercury adsorption capacity at 30℃, the silica nanotube MCM-41 was only about 35 % compared to the activated carbon Darco FGD commercially used for mercury adsorption, but it increased to 133 % when impregnated with 1.5 % sulfur. In addition, the furnace fly ash recovered from the waste copper regeneration process showed an efficiency of 523 %. Furthermore, the adsorption capacity was investigated at temperatures of 30 ℃, 80 ℃, and 120 ℃, and the best adsorption performance was found to be 80 ℃. MCM-41 is a silica nanotube that can be reused many times due to its rigid structure and has additional advantages, including no possibility of fire due to the formation of hot spots, which is a concern when using activated carbon.

Effect of resistance training on joint flexibility and muscle strength of upper extremities of elderly with impaired cognition (탄력저항성운동 프로그램이 인지기능저하 노인의 상지유연성 및 근력에 미치는 효과)

  • Kim, Shinmi;Lee, Yunjung;Kim, Hwanjoong
    • 한국노년학
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    • v.29 no.3
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    • pp.987-1000
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    • 2009
  • The purpose of the study was to examine the effect of resistance training on joint flexibility and muscle strength of upper extremities of institutionalized elderly with impaired cognition. The study design was pretest-posttest control group study and inclusion criteria were elderly aged 65-year older, MMSE score 23 or less, ones who had no serious physical and/or mental problem except impaired cognition, and were capable to carry out resistance training. After consents were obtained participants were randomly assigned. Pre-post evaluation was performed by staff nurses trained beforehand. Among those 4-week study period, experiment was carried out during 5 consecutive days a week for 3 weeks. ROM and extension range of shoulder joints and muscle strength of shoulders and hands for both sides were measured. Flexion, extension, abduction range of right shoulder joint was significantly improved. Flexion and extension muscle strength of left side shoulder and abduction muscle strength of both sides of shoulder were significantly improved. With the study result, it could be concluded that resistance training has therapeutic effects on joint flexibility and muscle strength. More studies adopted longer experimental period to evaluate timing of effect and extinction to refine the protocol are called for.

A Status of Technology and Policy of Nuclear Spent Fuel Treatment in Advanced Nuclear Program Countries and Relevant Research Works in Korea (선진 원자력발전국의 사용후핵연료 처리기술 및 정책현황과 우리나라의 관련연구 현황)

  • You, Gil-Sung;Choung, Won-Myung;Ku, Jeong-Hoe;Cho, Il-Je;Kook, Dong-Hak;Kwon, Kie-Chan;Lee, Won-Kyung;Lee, Eun-Pyo;Hong, Dong-Hee;Yoon, Ji-Sup;Park, Seong-Won
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.4
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    • pp.339-350
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    • 2007
  • Status on the spent nuclear fuel management policy and R&D plan of the major countries is surveyed. Also the prospect of the future R&D plan is suggested. Recently so-called fuel cycle nations, which have the reprocess policy of the spent fuel, announced new spent fuel management policy based on the advanced fuel cycle technology. The policy is focused to transmute highly radioactive material and material having a very long half-life, and to recycle the Pu and U contained in the spent fuel. In this way the radio-foxily of the spent fuel as well as the amount of the high level waste to be eventually disposed can greatly be reduced. Most of countries selected the wet process as a primary option for the treatment of the spent fuel since the advanced wet process, which is based on the existing PUREX process, looks more feasible as compared with the dry process. The wet process, however, is much more sensitive in terms of proliferation-resistance compared with the dry process. The pure Pu can easily be obtained by simply modifying the process. On the other hand the pure Pu can not be extracted in the dry process based on the high temperature molten salt process such as a pyroprocess. Even though the pyroprocess technology is very premature, it has a great merit. Thus it is necessary for Korea to have a long term strategy for pursuing a spent fuel treatment technology with a proliferation resistance and a great merit for the GEN-IV fuel cycles. Pyroprocess is one of the best candidates to satisfy these purposes.

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A Study on Intertextuality in <2013 Home of the Legends> (연작 웹툰 《2013 전설의 고향》에 나타나는 상호텍스트성 연구)

  • Yang, Hyelim
    • Cartoon and Animation Studies
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    • s.34
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    • pp.293-316
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    • 2014
  • (傳說의 故鄕) is a broadcast play as one-act play series based on Korean legends and folktales. It was first aired in 1977 from KBS and there has been borrowed from this play in a variety of genres such as books and movies as the name of this series securing its popularity and awareness of the public. In this context, this is a representative work for Korean horror genre. Recently, for example, a series webtoon <2013 Home of the Legends> is published on one of the main portal websites, NAVER from July, 2013. This webtoon is main subject of this study. The purpose of this study is to discuss how the genre characteristics of Korean horror in TV serial play transmitted and changed in series webtoon <2013 Home of the Legends>. TV serial play is a representative narrative based on Korean folktales, trying to change its narrative in the range of undestroyed folktale basic move with combining the original motifs. Serial webtoon <2013 Home of the Legends>, however, deconstructs this combination motif in folktale form and leads to new move in narrative. For Korean users accustomed to Korean folktale form as the architext, this will be expected as reversal and make catharsis. Meanwhile, the deconstruction of combination motif leads to extinction of its cause-and-effect, which consists the axis of original narrative form, with resulting powerless theme, good overcoming evil and punitive justice. The aspects of changes in <2013 Home of the Legends> represent new orientation of Korean horror.

THE EFFECT OF REPEATED MATERNAL SEPARATION ON GLUCOCORTICOID RECEPTOR AND CYCLOOXYGENASE-2 IN PREWEANLING RAT BRAIN (반복 모성 분리가 이유 전기 백서 뇌의 Glucocorticoid Receptor와 Cyclooxygenase-2에 미치는 영향)

  • Yoon, Doh-Joon;Chang, Hwan-Il;Song, Ji-Young;Bahn, Geon-Ho;Chung, Joo-Ho;Kim, Jong-Woo;Yoo, Hee-Jeong
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.15 no.1
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    • pp.91-100
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    • 2004
  • Objectives:The effects of repeated maternal separation on the expression of glucocorticoid receptor (GR) and cyclooxygenase-2(COX-2) in the hippocampus of rat pups at preweanling stage were evaluated. Methods:The experimental, Repeated Maternal Separation group(N=4) was separated from the mother for four hours a day over a period of ten days beginning with postnatal day 4. The Control group(N=4), on the other hand, did not separated from the mother at all. GR and COX-2 expression in the hippocampus was examined by immunohistochemistry on postnatal day 14. Results:It was determined that the number of GR-immunopositive cells in the dentate gyrus of the hippocampus was significantly increased in the Repeated Maternal Separation group. The numbers of COX-2-immunopositive cells in the CA1 and CA3 were also significantly higher in the Repeated Maternal Separation group. Conclusion:These results suggest that maternal separation may be a significant developmental stress that induces GR and COX-2 expression in the hippocampus of developing pups.

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Clinical Features of Indigenous Vivax Malaria in Children (소아에 발생한 삼일열 말라리아의 임상적 특성)

  • Lee, Eun Jin;Lee, Chong Guk;Cho, Chong Rae
    • Pediatric Infection and Vaccine
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    • v.10 no.2
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    • pp.200-207
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    • 2003
  • Purpose : Malaria is known to have been eradicated for a few decades through persistent national health program in South Korea. However, malaria caused by Plasmodium vivax has started to reappear incidiously among military personnel near to DMZ since 1993. After then, the number of malarial cases have been increased abruptly year by year. We analyzed the children of indigenous malaria who were diagnosed by peripheral blood smear and malarial antibody test with regards to epidemiologic and clinical manifestations. Methods : The study 13 cases below 15 years of age, who were confirmed as vivax malaria during from January 2000 to August 2003. We retrospectively analyzed epidemiologic data, clinical manifestations, laboratory findings and therapeutic responses. Results : All of 13 cases were indigenous and tested positive for Plasmodium vivax. Of 13 patients, 9 were male and 4 were female. Mean age of onset was $9.5{\pm}3.6$ years old. Ilsan(n=9) was the most prevalent area, the most patients(n=11) were presented in summer (from June to August). A characteristic feature of periodic 3 day fever in patients with P.vivax infection was reported in only 2 among 13 cases. Thrombocytopenia was most prominent findings, which was accompanied by 12 of 13 patients and pancytopenia was appeared in 3 patients on this study. The therapeutic responses of hydroxycholoquine were very good in all cases, and abnormal laboratory findings were recovered and no relapse during follow-up period. Conclusion : Vivax malaria is indigenous in Korea near to DMZ, but recently endemic area seemed to be extended southward. Plasmodium vivax is the cause of indigenous malaria of children. As for children with high fever accompanying thrombocytopenia in endemic area of Korea, malaria must be included in differential diagnosis whether the type of fewer is periodic 3 day fever or not. Malaria antibody test is helpful as a screening test for malaria.

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VR media aesthetics due to the evolution of visual media (시각 미디어의 진화에 따른 VR 매체 미학)

  • Lee, Dong-Eun;Son, Chang-Min
    • Cartoon and Animation Studies
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    • s.49
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    • pp.633-649
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    • 2017
  • The purpose of this study is to conceptualize the changing aspects of human freedom of observation and viewing as the visual media evolves from film to 3D stereoscopic film and VR. The purpose of this study is to conceptualize the aspect of freedom and viewing aspect from the viewpoint of genealogy. In addition, I will identify the media aesthetic characteristics of VR and identify the identity and ontology of VR. Media has evolved around the most artificial sense of human being. There is a third visual space called screen at the center of all the reproduction devices centering on visual media such as painting, film, television, and computer. In particular, movies, television, and video screens, which are media that reproduce moving images, pursue perfect fantasy and visual satisfaction while controlling the movement of the audience. A mobilized virtual gaze was secured on the assumption of the floating nature of the so-called viewers. The audience sees a cinematic illusion with a view while seated in a fixed seat in a floating posture. They accept passive, passive, and passively without a doubt the fantasy world beyond the screen. But with the advent of digital paradigm, the evolution of visual media creates a big change in the tradition of reproduction media. 3D stereoscopic film predicted the extinction of the fourth wall, the fourth wall. The audience is no longer sitting in a fixed seat and only staring at the front. The Z-axis appearance of the 3D stereoscopic image reorganizes the space of the story. The viewer's gaze also extends from 'front' to 'top, bottom, left, right' and even 'front and back'. It also transforms the passive audience into an active, interactive, and experiential subject by placing viewers between images. Going one step further, the visual media, which entered the VR era, give freedom to the body of the captive audience. VR secures the possibility of movement of visitors and simultaneously coexists with virtual space and physical space. Therefore, the audience of the VR contents acquires an integrated identity on the premise of participation and movement. It is not a so-called representation but a perfection of the aesthetic system by reconstructing the space of fantasy while inheriting the simulation tradition of the screen.

Metamorphism of the Buncheon and Hongjeas Granitic Gneisses (분천과 홍제사 화강암질 편마암체의 변성작용)

  • 김형수;이종혁
    • The Journal of the Petrological Society of Korea
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    • v.4 no.1
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    • pp.61-87
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    • 1995
  • On the basis of lithology, the Precambrian Hongjesa Granitic Gneiss can be locally zoned into granoblastic granitic gneiss, porphyroblastic granitic gneiss, migmatitic gneiss from its center to the marginal part. There are no distinct differences in mineral assemblages by lithologic zoning, but it partly shows the change of mineral assemblage in the adjacent with migmatitic gneiss, thus mineral assemblage can be subdivided into Zone I and Zone II. In terms of mineral compositions, the characteristics of Zone I are coexisting K-feldspar+muscovite+sillimanite. The characteristics of Zone II are (1) breakdown of muscovite, (2) coexisting garnetScordierite, (3) coexisting garnet+cordierite + orthoamphibole. The Buncheon Granitic Gneiss is mainly composed of augen gneiss. In the adjacent area with Honjesa Granitic Gneisses, Buncheon Granitic Gneiss has the mineral assemblage of sillimanite+biotite+K-feldspar+(kyanite). Kyanite occurs as relict grains in the Buncheon and Hongjesa Granitic Gneissess. Kyanite shows anhedral to subhedral form and coexists with sillimanite in only one of these samples. Garnet from a migmatitic gneiss (Zone 11) has relatively high $X_{Fe}$ value in core and rim. Garnet from a porphyroblastic granitic gneiss(Zone I) has relatively homogemeous core but compositionally-zoned rim. Biotites show various colour from greenish-brown, brown to reddish brown at maximum adsorption. Also, the Ti, and Mg content in biotites increases from Zone I to Zone II. The plagioclases shows the chemical composition of $Ab_{84}An_{16}$ -$Ab_{70}An_{30}$ (oligoclase) in Zone I and $Ab_{70}An_{30}$ -$Ab_{50}An_{50}$(andesine) in Zone 11. These variations indicate that the gneisses in the study area experienced a upperamphibolite facies. The presence of kyanite as relict grains indicates that the metamorphic rocks in this area exprienced a high-temperature/medium-pressure type metamorphism, followed by high-temperaturellow-pressure metamorphism. Metamorphic P-T conditions for each gneiss estimated from various geothermobarometers and phase equilibria are 698-$729^{\circ}C$/6.3-11.3 kbar in augen gneiss, 621-$667^{\circ}C$/1.0-5.4 kbar in migmatitic gneiss, and 602-$624^{\circ}C$/1.9-3.4 kbar in porphyroblastic granitic gneiss. These data suggest that the study area was subjected to a clockwise P-T path with isothermal decompression (dP/dT=about 60 bar/$^{\circ}C$).

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Dynamics of Barrel-Shaped Young Supernova Remnants (항아리 형태 젊은 초신성 잔해의 동력학)

  • Choe, Seung-Urn;Jung, Hyun-Chul
    • Journal of the Korean earth science society
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    • v.23 no.4
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    • pp.357-368
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    • 2002
  • In this study we have tried to explain the barrel-shaped morphology for young supernova remnants considering the dynamical effects of the ejecta. We consider the magnetic field amplification resulting from the Rayleigh-Taylor instability near the contact discontinuity. We can generate the synthetic radio image assuming the cosmic-ray pressure and calculate the azimuthal intensity ratio (A) to enable a quantitative comparison with observations. The postshock magnetic field are amplified by shearing, stretching, and compressing at the R-T finger boundary. The evolution of the instability strongly depends on the deceleration of the ejecta and the evolutionary stage of the remnant. the strength of the magnetic field increases in the initial phase and decreases after the reverse shock passes the constant density region of the ejecta. However, some memory of the earlier phases of amplification is retained in the interior even when the outer regions turn into a blast wave. The ratio of the averaged magnetic field strength at the equator to the one at the pole in the turbulent region can amount to 7.5 at the peak. The magnetic field amplification can make the large azimuthal intensity ratio (A=15). The magnitude of the amplification is sensitive to numerical resolution. This mens the magnetic field amplification can explain the barrel-shaped morphology of young supernova remnant without the dependence of the efficiency of the cosmic-ray acceleration on the magnetic field configuration. In order for this mechanism to be effective, the surrounding magnetic field must be well-ordered. The small number of barrel-shaped remnants may indicate that this condition rarely occurs.

The Distributional Patterns of Silla Burial Grounds and the Character of Outer Coffin Tombs in Jjoksaem Site, Gyeongju (쪽샘유적 신라고분 분포양상과 목곽묘의 성격)

  • Yun, Hyoung-Jun
    • Korean Journal of Heritage: History & Science
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    • v.50 no.4
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    • pp.198-221
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    • 2017
  • The Jjoksaem site is the eastern sector of Daereungwon Ancient Tomb Complex, Gyeongju(the 512th Historic site) called Wolseong North Burial Ground in academic community. The excavation and research of this site was conducted from 2007 to 2015, with the purpose of basic data offering for the restoration of Silla tumuli and development of ancient tomb park. As a result of the investigation, more than 700 new tombs were discovered except the 155 tumuli founded in the Japanese colonial era. Moreover, more than 70 percent of the smaller tombs, such as outer coffin tombs, were discovered here. There are four characteristics of outer coffin tombs in Jjoksaem site. First, it is recognized the Gyeongju-styled outer coffin tombs have a long rectangular shape, distinct from Gimhae-styled outer coffin tombs in a rectangular shape. Second, they are divided into three groups by the size of the grave area. This is indirectly related to the rank and the status of the buried person. Third, these tombs began to be constructed at the end of the 3rd century before the time of wooden chamber tombs covered by stone and earthen mound. They were ruined because of the new tombs constructed at the period of Maripgan. This reflects that the identity of the former tombs was not respected by the communities in the later generations. Outer coffin tombs were consistently made to the end of the era of wooden chamber tombs covered by stone and earthen mound. Lastly, the area of burial ground of outer coffin tombs is limited by wooden chamber tombs covered by stone and wooden mounds. Otherwise, the location of the burial ground for the deceased is limited by the status of the deceased. The idea that wooden chamber tombs covered by stone and earthen mound are located on the above ground turns out to be incorrect. In Jjoksaem site, there is little difference between the height of the circular burial protection stone and the height of the digging lines of the other tombs. In the case of No.44 tumulus, the lowest step of the circular burial protection stones is lower than those of the other tombs and tumuli. Research of outer coffin tombs at Jjoksaem site will be to suggest important academic data about the changing period from Saroguk, as the head of chiefdom union, to Silla, as state.