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Misconceptions of the Freshmen at High School about Plate Tectonics (판구조론에 관한 고등학교 1학년 학생들의 오개념)

  • Jeong, Kyoung-Jin;Jeong, Ku-Song;Moon, Byoung-Chan;Jeong, Jin-Woo
    • Journal of the Korean earth science society
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    • v.28 no.7
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    • pp.762-774
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    • 2007
  • The purpose of this study was to investigate misconceptions about plate tectonics which spread widely among freshmen at high school with drawing. For this, we chose 6 conceptions about plate tectonics by analysis of 7th curriculum and of 11 kinds of science textbooks. Questionnaire of drawing about plate tectonics were developed depending on them. Data was collected from 134 students who was freshmen at high school in Daegu. The result of this study was as follows. First, In structure of plate, 'upper mantle type' and 'crust type' misconceptions were more than half of the respondents. Second, In distribution of plate, 'cracked earthquake zone type' and 'earthquake frequency type' misconceptions were more than half of the respondents. Third, In formation of ocean ridge at oceanic crust- oceanic crust divergent plate boundary, 'divergence type' and 'collision type' misconceptions were more than half of the respondents. Fourth, In formation of mountain ridge at continental crust- continental crust convergent plate boundary, 'collision type' misconceptions were more than half of the respondents. Fifih, In formation of mountain ridge at oceanic crust- continental crust convergent plate boundary, 'subduction type' and 'fault type' misconceptions were more than half of the respondents. Sixth, In transform-fault at oceanic crust- oceanic crust transform-fault boundary, 'direction type' and 'section type' misconceptions were almost half of the respondents. In this study, students' drawings about plate tectonics showed similar misconceptions. This imply that drawing conceptions can be used by the strong evidence of misconceptions which spread widely among students. Furthermore, this study has a significance that this conclusion is useful to teachers as basic teaching-teaming materials of plate tectonics.

Possible Relationship between NAO and Western North Pacific Typhoon Genesis Frequency (북대서양 진동과 북서태평양 태풍발생빈도와의 관계)

  • Choi, Ki-Seon;Park, Sangwook;Chang, Ki-Ho;Lee, Jong-Ho
    • Journal of the Korean earth science society
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    • v.34 no.3
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    • pp.224-234
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    • 2013
  • This study examined a strong positive correlation between the North Atlantic Oscillation (NAO) index during June and the total tropical cyclone (TC) genesis frequency in the western North Pacific during July and August. To investigate a possible cause for this relationship, the mean difference between the highest positive NAO years and the lowest negative NAO years was analyzed by dividing into when the El Ni$\tilde{n}$o and La Ni$\tilde{n}$a years were included and when the El Ni$\tilde{n}$o and La Ni$\tilde{n}$a years were not included. When the El Ni$\tilde{n}$o and La Ni$\tilde{n}$a years were included, for the positive NAO years, the TCs mostly occurred in the northwestern region of tropical and subtropical western Pacific, and showed a pattern that migrate from the sea northeast of the Philippines, pass the East China Sea, and move toward the mid-latitudes of East Asia. In contrast, for the negative NAO years, the TCs mostly occurred in the southeastern region of tropical and subtropical western Pacific, and showed a pattern that migrate westward from the sea southeast of the Philippines, pass the South China Sea, and move toward the southern coast of China and Indochinese peninsula. These two different TC migration patterns affect the recurving location of TC, and for the positive NAO years, the recurving of TC was averagely found to take place in the further northeast. In addition, the migration patterns also affect the TC intensity, and the TCs of positive NAO years had stronger intensity than the TCs of negative NAO years as sufficient energy can be absorbed from the ocean while moving north in the mid-latitudes of East Asia. The TCs of negative NAO years showed weak intensity as they get weaken or disappear shortly while landing on the southern coast of China and the Indochinese peninsula. On the other hand, the above result of analysis is also similarly observed when the El Ni$\tilde{n}$o and La Ni$\tilde{n}$a years were not included.

Improvement of infrared channel emissivity data in COMS observation area from recent MODIS data(2009-2012) (최근 MODIS 자료(2009-2012)를 이용한 천리안 관측 지역의 적외채널 방출률 자료 개선)

  • Park, Ki-Hong;Suh, Myoung-Seok
    • Korean Journal of Remote Sensing
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    • v.30 no.1
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    • pp.109-126
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    • 2014
  • We improved the Land Surface Emissivity (LSE) data (Kongju National University LSE v.2: KNULSE_v2) over the Communication, Ocean and Meteorological Satellite (COMS) observation region using recent(2009-2012) Moderate Resolution Imaging Spectroradiometer (MODIS) data. The surface emissivity was derived using the Vegetation Cover Method (VCM) based on the assumption that the pixel is only composed of ground and vegetation. The main issues addressed in this study are as follows: 1) the impacts of snow cover are included using Normalized Difference Snow Index (NDSI) data, 2) the number of channels is extended from two (11, 12 ${\mu}m$) to four channels (3.7, 8.7, 11, 12 ${\mu}m$), 3) the land cover map data is also updated using the optimized remapping of the five state-of-the-art land cover maps, and 4) the latest look-up table for the emissivity of land surface according to the land cover is used. The updated emissivity data showed a strong seasonal variation with high and low values for the summer and winter, respectively. However, the surface emissivity over the desert or evergreen tree areas showed a relatively weak seasonal variation irrespective of the channels. The snow cover generally increases the emissivity of 3.7, 8.7, and 11 ${\mu}m$ but decreases that of 12 ${\mu}m$. As the results show, the pattern correlation between the updated emissivity data and the MODIS LSE data is clearly increased for the winter season, in particular, the 11 ${\mu}m$. However, the differences between the two emissivity data are slightly increased with a maximum increase in the 3.7 ${\mu}m$. The emissivity data updated in this study can be used for the improvement of accuracy of land surface temperature derived from the infrared channel data of COMS.

Accuracy Evaluation of Daily-gridded ASCAT Satellite Data Around the Korean Peninsula (한반도 주변 해역에서의 ASCAT 해상풍 격자 자료의 정확성 평가)

  • Park, Jinku;Kim, Dae-Won;Jo, Young-Heon;Kim, Deoksu
    • Korean Journal of Remote Sensing
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    • v.34 no.2_1
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    • pp.213-225
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    • 2018
  • In order to access the accuracy of the gridded daily Advanced Scatterometer (hereafter DASCAT) ocean surface wind data in the surrounding of Korea, the DASCAT was compared with the wind data from buoys. In addition, the reanalysis data for wind at 10 m provided by European Centre for Medium-Range Weather Forecasts (ECMWF, hereafter ECMWF), National Centers for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR, hereafter NCEP), Modern Era Retrospective-analysis for Research and Applications-2 (MERRA-2, hereafter MERRA) were compared and analyzed. As a result, the RMSE of DASCAT for the actual wind speed is about 3 m/s. The zonal components of wind of buoys and the DASCAT have strong correlation more than 0.8 and the meridional components of wind them have lower correlation than that of zonal wind and are the lowest in the Yellow Sea (r=0.7). When the actual wind speed is below 10 m/s, the EMCWF has the highest accuracy, followed by DASCAT, MERRA, and NCEP. However, under the wind speed more than 10 m/s, DASCAT shows the highest accuracy. In the nature of error according to the wind direction, when the zonal wind is strong, all dataset has the error of more than $70^{\circ}$ on the average. On the other hand, the RMSE of wind direction was recorded $50^{\circ}$ under the strong meridional winds. ECMWF shows the highest accuracy in these results. The RMSE of the wind speed according to the wind direction varied depending on the actual wind direction. Especially, MERRA has the highest RMSE under the westerly and southerly wind condition, while the NCEP has the highest RMSE under the easterly and northerly wind condition.

Distributions and Pollution History of Heavy Metals in Nakdong Estuary Sediments (낙동강 하구역 퇴적물 중금속의 분포와 오염의 역사 추정)

  • Cho, Jin-Hyung;Park, Nam-Joon;Kim, Kee-Hyun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.4
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    • pp.285-294
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    • 2000
  • In order to determine the horizontal and vertical distributions of metals and prospect the recent metal pollution history in Nakdong Estuary, we took surface and core sediments. Maximum value of organic matter occurs at the upstream site located 4 km from Nakdong barrage, and the concentration of trace metals (Zn, Cu, and Pb etc.) decrease seaward in the estuary. The sedimentation rates, based on $^{210}$Pb$_{ex}$ and $^{137}$Cs activities, were 0.34 cm/yr in inside of barrage (core 1) and 0.25 cm/yr in Changrim (core 4). Sediment mixing layer does not exist in core 1, where anoxic condition is known to be prevail. The topmost sediment layer of core 4 (<3.5 cm) is severely mixed. At sites 1 and 4, concentrations of Cu slowly increased during the period of 1920-1970, rapidly increased during 1970-1990, and followed by slight decrease after 1990. Zn contents increased in early 1960s and peaked in 1993, and followed by decrease after 1990s. Pb has increased continuously since early 1970s. At the downstream of the barrage, Cu and Zn have increased in the topmost layer. The trend of increase of Cu is evident after 1950 (11 cm in sediment depth). Overall trend of heavy metal concentration clearly indicates the pollution has been increasing after the construction of the barrage.

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Germ Cell Differentiations during Spermatogenesis and Ultrastructural Characteristics of Mature Sperms in Male Protothaca (Notochione) jedoensis (Bivalvia: Veneridae) (수컷 살조개, Protothaca (Notochione) jedoensis (Bivalvia: Veneridae)의 정자형성과정 중 생식세포 분화와 성숙정자의 미세구조적 특징)

  • Kim, Jin-Hee;Park, Young-Jae;Lee, Ki-Young;Choi, Moon-Sul;Seo, Won-Jae;Chung, Ee-Yung
    • Development and Reproduction
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    • v.14 no.4
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    • pp.269-279
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    • 2010
  • Some characteristics of germ cell differntiations and the function of accessory cells during spermatogenesis, and mature sperm ultrastructure in male Protothaca (N.) jedoensis were investigated by transmission electron microscope observations. The morphology of the spermatozoa of this species has a primitive type and is similar to those of other species in the subclass Heterodonta. Accessory cells, which are connected to adjacent germ cells, are involved in the supplying of the nutrients for germ cell development. The morphologies of the sperm nucleus and the acrosome of this species are the cylindrical type and cap shape, respectively. Spermatozoa are approximately $46{\sim}50{\mu}m$ in length including a long sperm nucleus (about $2.44{\mu}m$ in length), an acrosome (about $0.45{\mu}m$ in length), and tail flagellum (about $42{\sim}46{\mu}m$). The axoneme of the sperm tail shows a 9+2 structure. As some characteristics of the acrosomal vesicle structures, the basal and lateral parts of basal rings show electron opaque part (region), while the anterior apex part of the acrosomal vesicle shows electron lucent part (region). These characteristics of the acrosomal vesicle were found in the family Veneridae and other several families in the subclass Heterodonta. These common characteristics of the acrosomal vesicle in the subclass Heterodonta can be used for phylogenetic and systematic analysis as a taxonomic key or a significant tool. The number of mitochondria in the midpiece of the sperm of this species are four, as one of common characteristics appear in most species in the family Veneridae and other families in the subclass Heterodonta. However, exceptionally, only three species in Veneridae of the subclass Heterodonta contain 5 mitochondria. The number of mitochondria in the sperm midpiece can be used for the taxonomic analysis of the family or superfamily levels as a systematic key or an important tool.

A Study on 'Verfremdung' effects in visual advertisements with a special reference to the <017-I-Touch series, The Hand Transformed into a Web >, mobile network advertisement (동영상 광고에서 나타나는 '소격화' 효과에 관한 연구 - 광고 <017-I-Touch편 (손이 물갈퀴) >를 중심으로 -관어영시광고중소출현적‘맥생화’효과적연구(關於影視廣告中所出現的‘陌生化’效果的硏究))

  • Jin, Ri-Long;Ahn, Sang-Soo;Kim, Jong-Deok
    • Archives of design research
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    • v.18 no.2 s.60
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    • pp.37-46
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    • 2005
  • Today's advertisement is dominated by visual images, which deliver messages in the most efficient and engaging way. Vivid and live images, through multimedia, attract the viewer to consume the products being advertised. In this course, the effect of 'Verfremdung' or alienation is often detected. This terminology was at first used in a epic play of Bertolt Brecht to signify a specific effect to block the empathy of the audience by reminding them of their position as the audience separate from the play. 'Verfremdung' helps them to have a sense of objectivity and critical attitude toward the performance. Multimedia commercials nowadays exhibit such a quality together with 'viewer participation:' criticism on reality: and 'speed.' In an advertisement for Shinsegi Communications' mobile system titled <017-I-Touch series, the hand transformed into a web>, the copy, 'my blood type is 'i', ' is accompanied by six unrelated fictitious scenes in which the same ocean appears as a common denominator. Because there is no connection between the scenes, free imagination of the viewer has to be involved and thus plays a significant role in making them into a context. This fact dearly exhibit some characteristics of post- modern advertisement. Momentary 'Gap' and 'Difference' between scenes contribute to 'Verfremdung' or alienation' that makes it hard for the consumers to comprehend the content on the spot. Such an uneasy situation, however, keeps the viewers thinking about the advertisement itself. While repeatedly exposed to the alienated images, the viewers come to get involved in the advertisement, trying to make the fragmented images into a coherent context. In addition, the leaps between the scenes produce a sense of 'speed' in a context, which adds more impact to the way of delivering messages using multimedia. With the help of multimedia, 'Verfremdung: which was originally intended to bring about objective and critical altitude of the audience in a play, plays a crucial role in attracting the viewer's attention and conveying a specific message in a moment in contemporary advertisement.

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Diagnosis of Conflict Problem between the Marine Environmental Conservation and Development, and Policy Implication for Marine Spatial Planning (해양환경보전과 이용·개발의 상충 분석과 해양공간계획에 대한 시사점)

  • Lee, Dae In;Tac, Dae Ho;Kim, Gui Young
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.19 no.3
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    • pp.227-235
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    • 2016
  • This paper emphasized the necessity of the marine spatial planning (MSP) through the analysis of the major developmental projects which could make a contradiction based on the adequacy of the site selection and environmental impacts. The conflicting affairs between space utilization and management plan happen in the following ways: marine renewable energy development, sand mining, reclamation, construction of golf course in coastal area, thermal effluent and waste heat, erosion causing port development. The conflict of stakeholder continues caused by the accumulated environmental impact. For the reasons mentioned above, we found two things. First, it is necessary to comprehend the fact of developmental planning and MSP. Second, it is still unsatisfactory to connect the relevance of laws related to the spatial planning. For the reinforcement of marine environmental policy management, it is necessary to consolidate the property of site selection and assessment of developmental scale. Especially, while the strategic environmental assessment is in progress based on site selection and property of scale, consistent diagnosis is needed in the following concerns: the fact of the marine spatial planning, the relevance between national developmental plan and regional developmental plan, fisheries regulation, marine protected animals. For the environmentally sound and sustainable development (ESSD), MSP should have to be prepared based in a way of top-down including coastal and EEZ plan, relevance of ocean-use zoning and sector planning, 3-D spatial information. And also integrated information system have to be prepared through high-tech marine spatial information. In conclusion, consistent and relevant strategy for MSP should have to include the whole information related to the maritime affairs such as harbor, fishing port, fishing ground, coastal management, marine ecosystem generally.

Characteristics on De-CH4/NOx according to Ceramic and Metal Substrates of SCR Catalysts for CNG Buses (CNG 버스용 SCR 촉매의 세라믹과 메탈 담체에 따른 De-CH4/NOx 특성)

  • Seo, Choong-Kil
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.18-24
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    • 2018
  • The policy-making and technological development of eco-friendly automobiles designed to increase their supply is ongoing, but the internal combustion engine still accounts for about 95% of the automobiles in use. Also, in order to meet the stricter emission regulations of internal combustion engines based on fossil fuels, the proportion of after-treatments for vehicles and (ocean going) vessels is gradually increasing. Natural gas is a clean fuel that emits few air pollutants and has been used mainly as a fuel for city buses. In the long term, we intend to develop a new NGOC/LNT+NGCO/SCR combined system that simultaneously reduces the toxic gases, $CH_4$ and NOx, emitted from CNG buses. The objective of this study is to investigate the characteristics of $de-CH_4/NOx$ according to the ceramic and metal substrates of the SCR (Selective Catalytic Reduction) catalysts mounted downstream of the combined system. The V and Cu-SCR catalysts did not affect the $CH_4$ oxidation reaction, the two NGOC/SCR catalysts each coated with two layers began to oxidize $CH_4$ at $400^{\circ}C$, and the amount of $CH_4$ emitted was reduced to about 20% of its initial value at about $550^{\circ}C$. The two NGOC/SCR catalysts each coated with two layers showed a negative (-) NOx conversion rate above $350^{\circ}C$. The ceramic-based combined system reached LOT50 at $500^{\circ}C$, which was about 20% higher in terms of the $CH_4$ conversion rate than the metal-based combined system, showing that the combined system of NGOC/LNT+Cu-SCR is a suitable combination.

Distributional characteristics of risky phytoplankton species at inner and outer sites around Incheon seaport of Korea (인천항 내, 외에서 식물플랑크톤 위해종의 분포특성)

  • Kwon, Oh Youn;Kang, Jung-Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.11
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    • pp.6958-6965
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    • 2014
  • This study examined the occurring pattern of potential risky species and the related abiotic factors for port-specific environmental management considering the control of ballast water-induced foreign species at Incheon seaport. From a total of 62 species observed during the study, 13 red-tide and 7 toxic phytoplankton, normally occurring species in Korean waters, occurred from the seasonal investigation at the inner and outer sites of the Incheon seaport from 2007 to 2009. The number of potential risky phytoplankton was relatively high at the outer site of the port during summer and winter. Red-tide species, such as Skeletonema spp., Thalassiosira nordenskioldii, and Paralia sulcata, dominated the total standing crops at the inner site (avg. 72.4%) and outer site (avg. 77.6%) in spring and summer, being positively correlated with the concentrations of total suspended solids (TSS) and pH (p<0.05). In summer, the red-tide species (Skeletonema spp.) and toxic species (Alexandrium catenella, A. tamarense, Dinophysis acuminata and Pseudo-nitzschia spp.) co-dominated (avg. 74.2%) at the inner site, while Skeletonema spp. and P. sulcata predominated (avg. 67.2%) at the outer site. During the study periods, the toxic species were significantly and positively correlated with the chemical oxygen demand (COD), dissolved inorganic nitrogen, silicate and phosphate (p < 0.05). The chlorophyll-a (chl-a) concentration of phytoplankton at the outer site ranged from 1.49 to $5.46{\mu}g/L$ on average, which was 3-5 times higher than that at the inner site in spring, summer and autumn, whereas there was no difference in the concentration between inner (avg. $0.94{\mu}g/L$) and outer (avg. $0.95{\mu}g/L$) sites in winter. In summary, diverse red-tide species dominated and a relatively high chl-a concentration existed at the outer site, whereas a relatively high number of toxic species and low chl-a concentration was observed at the inner site in summer. The potential risky species can outbreak in association with the concentration of nutrients, COD and TSS, suggesting that distinctive management of potential risky species is needed considering the environmental characteristics of Incheon seaport.