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Analysis of Misconception on the North Korea Cold Current in Secondary-School Science and Earth Science Textbooks (중등학교 과학 및 지구과학 교과서 북한한류 오개념 분석)

  • Park, Kyung-Ae;Lee, Jae Yon;Lee, Eun-Young;Kim, Young Ho;Byun, Do-Seong
    • Journal of the Korean earth science society
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    • v.41 no.5
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    • pp.490-503
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    • 2020
  • Oceanic current and circulation have played an important role as regulators of the earth's energy distribution. The science and earth science textbooks for secondary schools based on the 2015 revised curriculum included a misconception of the seasonal variation of the North Korea Cold Current (NKCC) among the currents around the Korean Peninsula. To analyze this, the contents related to the NKCC were collected in the textbooks of five middle and six high schools, and a questionnaire survey was conducted on 30 middle school science teachers. The survey consisted of questions about whether the textbook mentions the NKCC and whether there is an error in the concept of the temporal variation of the NKCC, and the teachers' free opinions related to the NKCC were collected. The textbooks suggest that the NKCC is strongest in winter, which is not consistent with scientific findings so far. In fact, there is scientific evidence that the NKCC is the strongest in the summer. In this study, the causes and processes of misconceptions were investigated. According to an analysis of the survey, most teachers had an knowledge that the NKCC is stronger in winter. These errors began with a misconception of the terms, which teachers had imprinted on their memory as firm knowledge. These misconceptions originated from the knowledge that teachers themselves acquired from their secondary school years and have long been transferred back to teachers and students without revising the misconceptions of textbooks. This situation is expected to have a seriously recurrent structure that produces students' serious misconceptions in the future. Therefore, this study summarizes existing results on the seasonal variability of the NKCC and suggests the necessity for re-education to improve teachers' professionalism and to eliminate the misconceptions of teachers and students.

Analysis of Misconceptions on Oceanic Front and Fishing Ground in Secondary-School Science and Earth Science Textbooks (중등학교 과학 및 지구과학 교과서 조경 수역 및 어장에 관한 오개념 분석)

  • Park, Kyung-Ae;Lee, Jae Yon;Kang, Chang-Keun;Kim, Chang-Sin
    • Journal of the Korean earth science society
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    • v.41 no.5
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    • pp.504-519
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    • 2020
  • Oceanic fronts, which are areas where sea water with different properties meet in the ocean, play an important role in controlling weather and climate change through air-sea interactions and marine dynamics such as heat and momentum exchange and processes by which properties of sea water are mixed. Such oceanic fronts have long been described in secondary school textbooks with the term 'Jokyung water zone (JWC hereafter) or oceanic front', meaning areas where the different currents met, and were related to fishing grounds in the East Sea. However, higher education materials and marine scientists have not used this term for the past few decades; therefore, the appropriateness of the term needs to be analyzed to remove any misconceptions presented. This study analyzed 11 secondary school textbooks (5 middle school textbooks and 6 high school textbooks) based on the revised 2015 curriculum. A survey of 30 secondary school science teachers was also conducted to analyze their awareness of the problems. An analysis of the textbook contents related to the JWC and fishing grounds found several errors and misconceptions that did not correspond with scientific facts. Although the textbooks mainly uses the concept of the JWC to represent the meeting of cold and warm currents, it would be reasonable to replace it with the more comprehensive term 'oceanic front', which would indicate an area where different properties of sea water-such as its temperature, salinity, density, and velocity-interact. In the textbooks, seasonal changes in the fishing grounds are linked to seasonal changes in the North Korean Cold Current (NKCC), which moves southwards in winter and northwards in summer; this is the complete opposite of previous scientific knowledge, which describes it strengthening in summer. Fishing grounds are not limited to narrow coastal zones; they are widespread throughout the East Sea. The results of the survey of teachers demonstrated that this misconception has persisted for decades. This study emphasized the importance of using scientific knowledge to correct misconceptions related to the JWC, fishing grounds, and the NKCC and addressed the importance of transferring procedures to the curriculum. It is expected that the conclusions of this study will have an important role on textbook revision and teacher education in the future.

Development and Adult Life Span of Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae) Fed on the Melon Aphid, Aphis gossypii Glover or the Green Peach Aphid, Myzus persicae($S\"{u}lzer$) (Homoptera: Aphididae) (목화진딧물(Aphis gossypii)과 복숭아혹진딧물(Myzus persicae) (Homoptera: Aphididae)을 먹이로 한 진디혹파리[Aphidoletes aphidimyza (Rondani)] (Diptera: Cecidomyiidae)의 발육 및 성충수명)

  • Kim Tae-Heung;Kim Ji-Soo
    • Korean journal of applied entomology
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    • v.43 no.4 s.137
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    • pp.297-304
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    • 2004
  • The development of Aphidoletes aphidimyza, an aphidophagous gall midge, was studied at various constant temperatures ranging from 15 to $35^{\circ}C$, with $65{\pm}5\%$ RH, and a photo-period of 16L:8D. When A. aphidimyra was fed either on Aphis gossypii or Myzus persicae, it took 43.9 and 44.5 days, respectively, to develop from egg to pupa at $15^{\circ}C$, whereas at $25^{\circ}C$, 14.3 and 15.8 days. The developmental zero was 10.7 and $10.0^{\circ}C$, respectively, while the effective accumuative temperatures were 210.8 and 245.5 day-degrees. The nonlinear shape of temperature-dependent development, shown by A. aphidimyza when fed on either species of the aphids, was well described by the modified Sharpe and DeMichele model. When distribution model of completion time of development for each growth stage was expressed as physiological age and fitted to the Weibull fuction, the completion time of development gradually shortened from egg to larva, and to pupa. In addition, the coefficient of determination $r^2$ ranged between 0.86-0.93 and 0.85-0.94, respectively providing a good approximation of cumulative developmental rates. The life span of adult was 8.7 and 9.2 days at $15^{\circ}C$, and 3.1 and 2.7 days at $30^{\circ}C$, respectively. Egg incubation period was relatively short at $35^{\circ}C$ but hatchability was less than $50\%$ and the mortality of the larva at $35^{\circ}C$ reached $100\%$. At $30^{\circ}C$, the time of development lengthened and the adult longevity was short suggesting ill effect of high temperatures. Even though the life span of adults at $15^{\circ}C$ was relatively long, none moved freely in the rearing cage and no oviposition occurred. Accordingly, in case A. aphidimyza is adopted to suppress phytophagus aphid populations, it could be applicable to cropping systems with ambient temperatures above $20^{\circ}C$ and below $30^{\circ}C$. Within this range, A. aphidimyza adults was observed to be active and oviposit fully.

Overwintering Conditions of the Diamondback Moth and Genetic Variation of Overwintering Populations (배추좀나방 월동 조건과 야외 월동집단의 유전적 변이)

  • Kim, Eunseong;Choi, Bongki;Park, Youngjin;Cha, Ookhyun;Jung, Chungryel;Lee, Daeweon;Kim, Kwangho;Kim, Yonggyun
    • Korean journal of applied entomology
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    • v.53 no.4
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    • pp.355-365
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    • 2014
  • It has been unclear whether the diamondback moth, Plutella xylostella can overwinter in Korean field conditions. This study determined overwintering conditions of P. xylostella by conducting field exposure tests based on its cold tolerance and monitoring overwintering populations by direct examination of overwintering larval habitats and capturing adults with sex pheromone traps. In addition, the overwintering populations were analyzed using polymorphic genetic markers to trace their sources. When all immature stages of P. xylostella were exposed to $-5^{\circ}C$, which was the temperature much above their supercooling points, they significantly suffered with direct cold injuries, where larval stage was most tolerant to the cold injury. However, the exposure to $5^{\circ}C$ for a long period (4 weeks) did not give any significant cold injury to nonfeeding stages, while this treatment gave lethality to larval stage without diet. When all developmental stages of P. xylostella were exposed to open field conditions during winter, they exhibited significant decreases of survival rates. However, some protected and indoor conditions reduced the cold injuries and the diet provision significantly increased larval survival rates. Adult monitoring with sex pheromone during winter period indicated that the first captures were observed at similar periods at different locations (${\approx}260$ Km apart). The overwintering adults were captured until early April. Genetic variation of these overwintering populations was analyzed with polymorphic molecular markers, indicating significant genetic divergences among the overwintering populations. This study indicates that P. xylostella can overwinter in southern Korean fields or some protected greenhouses with host plants.

Effect of Soybean Meal and Soluble Starch on Biogenic Amine Production and Microbial Diversity Using In vitro Rumen Fermentation

  • Jeong, Chang-Dae;Mamuad, Lovelia L.;Kim, Seon-Ho;Choi, Yeon Jae;Soriano, Alvin P.;Cho, Kwang Keun;Jeon, Che-Ok;Lee, Sung Sil;Lee, Sang-Suk
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.1
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    • pp.50-57
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    • 2015
  • This study was conducted to investigate the effect of soybean meal (SM) and soluble starch (SS) on biogenic amine production and microbial diversity using in vitro ruminal fermentation. Treatments comprised of incubation of 2 g of mixture (expressed as 10 parts) containing different ratios of SM to SS as: 0:0, 10:0, 7:3, 5:5, 3:7, or 0:10. In vitro ruminal fermentation parameters were determined at 0, 12, 24, and 48 h of incubation while the biogenic amine and microbial diversity were determined at 48 h of incubation. Treatment with highest proportion of SM had higher (p<0.05) gas production than those with higher proportions of SS. Samples with higher proportion of SS resulted in lower pH than those with higher proportion of SM after 48 h of incubation. The largest change in $NH_3$-N concentration from 0 to 48 h was observed on all SM while the smallest was observed on exclusive SS. Similarly, exclusive SS had the lowest $NH_3$-N concentration among all groups after 24 h of incubation. Increasing methane ($CH_4$) concentrations were observed with time, and $CH_4$ concentrations were higher (p<0.05) with greater proportions of SM than SS. Balanced proportion of SM and SS had the highest (p<0.05) total volatile fatty acid (TVFA) while propionate was found highest in higher proportion of SS. Moreover, biogenic amine (BA) was higher (p<0.05) in samples containing greater proportions of SM. Histamines, amine index and total amines were highest in exclusive SM followed in sequence mixtures with increasing proportion of SS (and lowered proportion of SM) at 48 h of incubation. Nine dominant bands were identified by denaturing gradient gel electrophoresis (DGGE) and their identity ranged from 87% to 100% which were mostly isolated from rumen and feces. Bands R2 (uncultured bacterium clone RB-5E1) and R4 (uncultured rumen bacterium clone L7A_C10) bands were found in samples with higher proportions of SM while R3 (uncultured Firmicutes bacterium clone NI_52), R7 (Selenomonas sp. MCB2), R8 (Selenomonas ruminantium gene) and R9 (Selenomonas ruminantium strain LongY6) were found in samples with higher proportions of SS. Different feed ratios affect rumen fermentation in terms of pH, $NH_3$-N, $CH_4$, BA, volatile fatty acid and other metabolite concentrations and microbial diversity. Balanced protein and carbohydrate ratios are needed for rumen fermentation.

Study on Public Awareness of establishing Marine Protected Areas - Case Study of Guimaras Province, Philippines using Contingent Valuation Method (해양보호구역의 설정에 대한 대중인식도 연구 - 조건부 가치측정법을 이용한 필리핀 기마라스주의 사례)

  • Kim, Tae-Goun
    • Journal of Navigation and Port Research
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    • v.38 no.6
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    • pp.663-672
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    • 2014
  • In Korea and the Philippines, as well as all over the world, with the recognition of the importance of marine ecological resources, the marine protected areas(MPA) have been established and managed to protect and preserve these resources. While the number of marine protected areas for marine ecological resources protection has been increased, there is main problem that the most of MPAs do not achieve their intended management objectives. the effective management. Because of the positive and negative impacts on local communities and fishermen as direct stockholders, there has been ongoing debate on the pros and cons of implementing MPAs. Accordingly, this research conducted a case study of establishing Marine Protected Areas in Guimaras, Philippines because Philippines fisheries code of 1998 (Republic Act 8550), which is enacted to manage, conserve and protect fishery resources, obliged local governments to designate no less than 15% of jurisdictional municipal water as fisheries resource protection areas for a long time. To do this, a dichotomous-choice contingent-valuation survey was conducted in the two municipalities of Guimaras, Philippines to investigate public opinion in debates over MPAs and to estimate willingness to pay (WTP) for MPAs to protect and conserve marine habitats for fishery resources. Because of the expected economic costs by prohibiting fishing activities within the establishing newMPA, 58.7% of respondents thought the costs should be compensated, but 91.4% respondents voted in favor of increasing MPAs for fisheries resources as a protective measure. Finally, with Contingent Valuation Method(CVM), the aggregate mean WTP (375.5ha) of San Lorenzo and Sibunag residents in Guimaras Province, Philippines for establishing the additional MPA in their municipality waters was estimated to $1,046,791. Therefore, these findings could be used as a valuable data for establishing effective management plan of MPAs in Korea.

A Study on Subcontract Animation in Korea during the Industrialization Era - Centered around Animations in 1970-80s - (산업화시대 한국 하청애니메이션에 대한 연구 - 1970-80년대 애니메이션을 중심으로 -)

  • Kim, Jong-Ok
    • Cartoon and Animation Studies
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    • s.43
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    • pp.47-75
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    • 2016
  • This study has analyzed the history of the subcontract animation in Korea that began with Golden Bat of TBC Animation Division in 1966 to 1980s and shed the light on the history of subcontract animation that has been processed over 30 years in Korean animation. For this purpose, through the outlined status of subcontract animation, such as, production company, production status, scale of industry and so forth, the status of the OEM industry then has been checked and it links the solidified background of animation into subcontract production industry with the situation in time for analysis. In addition, on the basis of the foregoing, it is intended to broaden the horizon of the history of animation through the analysis on new search for facilitating the creative animation by overcoming the issues and limits generated by the subcontract animation industry. 1970s was the time that the national objective is to advance heavy-chemical industry and export-led economic growth. From the late 1970s, the animation has been spot lighted as the main-stream export industry through the overseas subcontract orders for animation. Expansion of the subcontract animation production has been influenced from the national policies on public culture, dispersion of color TV, facilitation of video production market and other media changes of the time that led the decline of animation audiences in theaters, and another cause would be in lack of platform of broadcasting companies that avoided the independent animation production for its economic theory. The subcontract animation industry may have the positive evaluation in the aspect of expanding the animation environment, such as, structuring of animation infra, development of new human resources and etc. However, the technology-incentive 'production'-oriented advancement has created distorted structure in advancing the professional human resources due to the absence of 'pre-production' of planning and others as well as the insufficient perception on 'post production (post work)', and it was unable to formulate domestic market by re-investing the capital accumulated for OEM industry into the production of creative animation and it has been assessed as negative aspect. Animation is a cultural and spiritual product of a country. Therefore, the systematic support policy for the facilitation of the creative animation, such as, development of professional human resources, creation of outstanding work, formation of market to make the pre-circulation structure and so forth has to be sought. However, animation is an industry, but there is no perception that it is a cultural industry based on the creativeness, not hardware-oriented manufacturing business. Such a lack of recognition, there was no policies to make the market and facilitate the creative animation by the animation of Korea for this period through the long-term plan and investment for independent work production. Such an attempt is newly begun through diverse searches for protection and advancement of creative animation in Korea after 1990s.

Microtuberization and Morphological Development by Culture Condition In Vitro Node Culture of Potato (감자절간 기내배양에서 소괴경의 형성과 형태적 발달)

  • Hwang, Hye-Yeon;Lee, Young-Bok
    • Journal of Plant Biotechnology
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    • v.34 no.4
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    • pp.331-338
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    • 2007
  • One-node stem pieces ca. 1 cm in length containing a axillary bud and a fully expanded leaf were obtained from it in vitro plants of potato (Solanum tuberosum L.). Leaves were removed and the nodes were cultured on the MS medium to investigate the effects of temperature, day length, sucrose, and CCC in microtuber formation and development. The fresh weight of microtubers after 80 days increased significantly at 8% sucrose and $20^{\circ}C$ compared with $28^{\circ}C$. The tuberization and development were reduced at $28^{\circ}C$ except short-day treatment of 8 hours at 8% sucrose. The fresh weight and diameter were increased on the culture medium added CCC 500 mg/L. The potato tuberization was promoted under short daylength, and it showed great effect by treatment with the CCC. Though the tuberization was promoted at low temperature of $20^{\circ}C$ in a histologic change of an axillary bud part cell of a potato, the cells were able to observe the swelling growth. Swelling growth of tissue was stimulated in the darkness and was more remarkable by addition of CCC. In particular, in the visual ratio of cell division for each position in the tissue, the cortex part showed larger ratio of cell expansion than that of the pith part. The effect of CCC was identified at 8% sucrose in the darkness. The effect of CCC was not showed in sucrose 3% under long daylength of 16 hours. As a result, the fact of a substance with AGPase important for starch composition was certified by the result with the inclose of AGPase activity on high concentration of sucrose, CCC, and dark treatment by which tuber formation and development are promoted.

기호학적 분석을 통한 영상애니메이션 연구

  • Lee Jong-Han
    • Broadcasting and Media Magazine
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    • v.10 no.1
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    • pp.85-98
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    • 2005
  • About the phenomenon of being imaged of everything, the scholars of the humanities who had studied on the simple reason structure in a text have been in a big agony how accept it. Especially, semiologists have studied about this for a long time and the points at issues of Saussure, Peirce as well as Umbeto Eco are more outstanding. Being based upon his philosophic interesting from medieval esthetics to modern semiotics, Eco was very concerned about the field of general esthetics and poputar arts like television and cartoons. He connected the mutual open-relations between 'signifier' and 'signified' debated in Semiotics with the open and vague modern arts and regarding it as a deviation from the custom, intensively studied the film-media. Saussure is a representative figure of semiotics and explained Sign and the character of semiotics as the division into two parts such as signifier/ signified, form/ substance, langue/ parole, synchrony/ diachrony. The triadic semiotics (the theory that Sign is composed of the triadic structure like sign, referent and interpretant) of Peirce put the new item- 'interpretant' in sign and referent to connect them and open the possibility to introduce time in to the Sign. In this paper, I try to analyze a cartoon film in the semiotic structure with the systemic, reasonable and logical approach and analysis as as possible. While the images shown through a film were depended on the romantic and impressional judge in the past, due to semiotics, it' s quite possible to correlate the procedure of symbolization to social coherence so that we analyze the incredible power of images to suck audiences with the systemetic Sign. I accept all ot film-images including a cartoon film as not the simple esthetic arts but a social custom and system, want to serve as a aid to properly understand world and humanbeings and prevent the film-image from being mystic. A cartoon and a cartoon film which were begun with the link of a text and an illustration give shape to all of images such as materials, places and even thoughts with a cartoon icon existed in only a cartoon. A cartoon and a cartoon film simply and exquistely conceptualize the complex and vague attribute of an organic creature and extend them infinetly beyond language. However, it can be exploited as a mysticism to temptate the general public and a faking material. In addition to that, it can distort our world-knowledge engaging a political power and the massive power of mass media. In this paper, being based on semiotics to approach a cartoon film in a scientific and organic system, I conclude that a non-linguistic cartoon expression is entangled with the manifold signs and implies the supplementary meanings just like a regular linguistic expression. It remarks that the iconic images of a cartoon film are composed of the social codes and can be analyzed on grounds of a linguistic system.

The Study on Integration of Gravities Anomaly in South Korea and Its Vicinities by Using Spherical Cap Harmonic Analysis (구면캡 조화분석을 이용한 남한 및 그 주변지역의 중력이상 통합에 관한 연구)

  • Hwang, Jong-Sun;Kim, Hyung-Rae;Kim, Chang-Hwan;You, Sang-Hoon
    • Economic and Environmental Geology
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    • v.41 no.2
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    • pp.211-217
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    • 2008
  • The gravity anomalies that observed by ground and shipborne survey and calculated from GRACE satellite are combined by using spherical cap harmonic analysis (SCHA). In this study, ground gravity data from Korea Institute of Geoscience and Mineral Resource(KIGAM) and shipborne gravity data from National Ocean Research Institute(NORI) and Korea Ocean Research and Development institute(KORDI) were used. L-2 level GRACE Gravity Model (GGM02C) was also used for satellite gravity anomaly. The ground and shipborne surveyed data were combined and gridded using Krigging method with 0.05 degree interval and GRACE data were also gridded using the same method with 0.05 degree to harmonize with the resolution of SCHA that has coefficient up to 80. Generalized Minimal Residual(GMRES) inversion method was implemented for calculating the coefficients of SCHA using the gridded ground and satellite gravity anomalies that had 0 km and 50 km altitude, respectively. The results of inversion method showed good correlation of 0.950 and 0.995 with original ground and satellite data. The gravity anomaly using SCHA satisfies Laplace's equation, therefore, using these SCHA coefficients, gravity anomaly can be calculated at any altitude. In this study, gravity anomaly was calculated from 10 km to 60 km altitude and each altitude, very stable results were shown. The ground and shipborne gravity data that have higher resolution and satellite data in long wavelength are harmonized well with SCHA coefficients and successfully applied in South Korea area. If more continuous survey and muti-altitude surveyed data like airborne data available, more precise gravity anomaly can be acquired using SCHA method.