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Beliefs About Gifted Education and Classroom Practices of the Science Teachers at Science Academy in Korea (과학영재학교 과학교사들의 영재교육에 대한 신념과 교수활동 유형)

  • Kim, Kyung-Jin;Kwon, Byung-Doo;Kim, Chan-Jong;Choe, Seung-Um
    • Journal of The Korean Association For Science Education
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    • v.25 no.4
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    • pp.514-525
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    • 2005
  • The most important factor in providing education to gifted students as well as to students in general are the teachers themselves. However, at present in Korea, most of the teachers in charge of education for the gifted are educated by in-service training programs only for a short period of time. It is doubtful whether the teachers, who have taught ordinary students in general, can teach gifted students effectively only after completing such a short course. This research investigated the relationship between the teachers' beliefs about educating the gifted and the teachers' classroom practices in a Science Academy through case studies. The guiding questions for this study are as follows: First, what beliefs do the participating teachers have about education for the gifted? Second, how are the participants' beliefs reflected in their classroom practices? Of the five participants, two are physics teachers, two are biology teachers, and one is an earth science teacher. I observed and videotaped four classroom practices for each participant and conducted an in-depth interview with each participant. Further data were collected through e-mails with the participants. All data were carefully transcribed and analyzed. The results are as follows: Beliefs about education for the gifted do not exist independently, and form a belief system connecting with beliefs about teaching and learning, and subject matter. And the belief systems of participants can be divided into "student-centered," "teacher-centered," and "conflict chaos." In the classes of the participants who have "student-centered" belief system, students' questions or opinions played an important role and the participation structure in the classroom was determined by the students. On the contrary, participants who have "teacher-centered" belief system focused on teaching contents as much as possible in their classes. These teachers played a heavy role and formed a participation structure where students depended on their teacher's intellectual authority and therefore participated in their class passively. A participant who have "conflict chaos" belief did not form a firm belief system yet, and traditional beliefs about teaching and learning were reflected a lot in her classes. The research results imply teachers' beliefs play an important role in classroom practices and beliefs about teaching and learning and subject matter as well as beliefs about education for the gifted are important factors for teachers who guide gifted students. Additionally, I make some suggestions for the improvement of teacher education for the gifted.

Reliability Verification of FLUKA Transport Code for Double Layered X-ray Protective Sheet Design (이중 구조의 X선 차폐시트 설계를 위한 FLUKA 수송코드의 신뢰성 검증)

  • Kang, Sang Sik;Heo, Seung Wook;Choi, Il Hong;Jun, Jae Hoon;Yang, Sung Woo;Kim, Kyo Tae;Heo, Ye Ji;Park, Ji Koon
    • Journal of the Korean Society of Radiology
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    • v.11 no.7
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    • pp.547-553
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    • 2017
  • In the current medical field, lead is widely used as a radiation shield. However, the lead weight is very heavy, so wearing protective clothing such as apron is difficult to wear for long periods of time and there is a problem with the danger of lethal toxicity in humans. Recently, many studies have been conducted to develop substitute materials of lead to resolve these problems. As a substitute materials for lead, barium(Ba) and iodine(I) have excellent shielding ability. But, It has characteristics emitting characteristic X-rays from the energy area near 30 keV. For patients or radiation workers, shielding materials is often made into contact with the human body. Therefore, the characteristic X-rays generated by the shielding material are directly exposured in the human body, which increases the risk of increasing radiation absorbed dose. In this study, we have developed the FLUKA transport code, one of the most suitable elements of radiation transport codes, to remove the characteristic X-rays generated by barium or iodine. We have verified the reliability of the shielding fraction of the structure of the structure shielding by comparing with the MCPDX simulations conducted as a prior study. Using the MCNPX and FLUKA, the double layer shielding structures with the various thickness combination consisting of barium sulphate ($BaSO_4$) and bismuth oxide($Bi_2O_3$) are designed. The accuracy of the type shown in IEC 61331-1 was geometrically identical to the simulation. In addition, the transmission spectrum and absorbed dose of the shielding material for the successive x-rays of 120 kVp spectra were compared with lead. In results, $0.3mm-BaSO_4/0.3mm-Bi_2O_3$ and $0.1mm-BaSO_4/0.5mm-Bi_2O_3$ structures have been absorbed in both 33 keV and 37 keV characteristic X-rays. In addition, for high-energy X-rays greater than 90 keV, the shielding efficiency was shown close to lead. Also, the transport code of the FLUKA's photon transport code was showed cut-off on low-energy X-rays(below 33keV) and is limited to computerized X-rays of the low-energy X-rays. But, In high-energy areas above 40 keV, the relative error with MCNPX was found to be highly reliable within 6 %.

A Study on the Locational Factors of Small Industry in Pusan, Korea (釜山市 小規模工業의 立地와 意思決定에 關한 硏究)

  • Lee, Hee-Yul
    • Journal of the Korean Geographical Society
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    • v.28 no.1
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    • pp.16-39
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    • 1993
  • This study aims to analyze the locational factors which the small firm enterpreneurs in Pusan City mainly consider in deciding location choices for their plants, and then to grasp the differences of the factors in terms of nature of firms, managerial personal characteristics and zoning areas. In order to implement the purpose of the rescarch, data are collected from selected small firm enterpreneurs throughthe questionaire. The main results are summerized as follows. First, it is pointed out that small firm indu-strialists for the regional choice consider crucial rationale as non-economic factor of personal reson with additional consideration of transpor-tation, infrastructure, service, market and labor forces. But in selection of site, they are apt to have high regard on the such factors as infra-structure, service, land and transportation factor. These factors to select the site demonstrate differentiation in terms of character of enter-prises, managerial characteristics and zoning areas. For example, land in the light of indu-strial sector is regarded as an important factor with longer the time of the establishment of firms or more aged or experienced enterpreneurs, wheras infrastructure and service in the heavy and chemical industrial sector are taken up as an important one with shorter the time of establishment of firms or less aged or experienced or higher educational background of enterpren-eurs. In addition, the non-economic factors such as the residential livebility and personal reason are picked up as important factors with smaller the firm or more aged or experienced, lesser educational background of entrepreneurs. Taking into consideration zoning area, infra-structure and service in the industrial area such as the exclusive and semi-industrial areas, land in green belt area, and transportation in the commercial and residential areas are singled out as the most important factors respectively. In addition, the non-economic factors of the resi-dential livability and personal reason in the non-industrial areas are also highly regarded. Second, land is picked up as the most impor-tant one of pulling factors toward the present site while other factors such as infrastructure, service, personal reason are also regarded as the secondary reason for the move-in decision; the pulling factors for the present plant location show somewhat differences in terms of the charcter of the enterprises, managerial chara-cteristics and zoning areas. Policy measures including land, infrastructure under the environmental aspects, service and transportations are, in turn, pointed out as the important ones for pushing factors. Meanwhile, as the important staying factor in the present place, transportation, infrastructure and service under the aspect of the agglomeration benefit, market, personal reason are considered. The pushing and staying factors also shows somewhat distinctive differences in terms of the character of enterprises, managerial chracteristics and zoning area. In the case of zoning area, land is regarded as the most important factor to move out, especially in the non-industrial areas inclu-ding the commerical and residential areas policy measures, infrastructure and service are indicated as important factors to move out. In the mean-time, as the important staying factor, industria-lists in the exclusive and semi-industrial areas point out transportation, infrastructure and service. Whereas the counterparts in the com-mercial area regard transportation and market as important factor, those in the residential area consider the non-economic factors such as personal reason and residential livability. Taking into consideration the result of this analysis, it is identified that the locational chara-cteristics of the intraurban small firm industries are not only associated with the character of enterprises, but also with manager's personal character and the trait of zoning area. Therefore, it seems that the thorough review or examination of enterprises, industrialists' characteristics and zoning areas will have meanin-gful significance in attemption explanation of small firm industries at the intrauban scale in the future. Especially, it appears that the eco-nomic factors such as land, infrastructure, service, transportation, and the non-economic factors such as residential livability and personal reason play together important parts to determine the locational choice of small firm industries along with non-industrial benefit. Thus, such status reveals the obvious implication for the intraurban industrial policy in the future.

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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.

Industrial restructuring and uneven regional development in the 1980s (산업구조조정과 지역불균등발전 : 1980년대)

  • ;Choi, Byung-Doo
    • Journal of the Korean Geographical Society
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    • v.29 no.2
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    • pp.137-165
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    • 1994
  • Structural adjustment of industry (or industrial restructuring) seems to be inherent in the process of capitalist economic development, which tends to be proceeded with shifts from one stage to another in order to overcome structural crises generated in each stage. The structural adjustment of industry is necessarily accompanied with regional restructuring, since it is not only projected on spece, but also mediated by space. Such a restructuring necessitates industrial and uneven regional devlopment through which capital can seek excessive profits over the rate of socio-spatial average. The industrial restructuring and uneven regional development in the 1980s in Korea can be seen as a process in which capital attempted with a strong support of the govenment to overcome the crises in the end of 1970s and hence to go on rapid economic growth. In this process, capital, especially monopoly capital concentrated into few conglomerates, pursued both extensive expansion and intensive development of industry simultaneously. In results, the Korean economy could eliminate some of peripheral characters and maturate the Fordist accumulation system. The extensive expansion of the Korean industry in the 1980s was stimulated mainly through the enlargement and adjustment of investment for equipment facilities which was planned to exclude or rationalize traditional light industries on some places, and to continue rapid growth of key heavy-chemical industries, especially of fabricated metal industry, on other places. In this process, keeping mainly the existing developmental axis which polarized the Seoul Metroplitan region and the Southeast region in Korea, the enhancing spatial mobiiity of capital and the further differentiating division of labour enforced a tendency of concentration of all types of industry in the Seoul Metropolitan region, and at the same time provoked the diffusion of some industries over Jeolla and Chungchong regions in a considerable extent. The intensive development of industriai structure in the 1980s was pursued through the strategic encouragement of subcontracting small firms mainly which produced assembling components, the technical enhancement and factory (semi-) automation, and the enrichment of service industries for estate management, finance, distribution and retailing which supported and complemented the production of goods. In this process, enabling capital to extend and elaborate its domination over space through the reorganization of regulating systems, the Fordist division of labour generated a socio-spatial hierarchy in the nation-wide scale that characterized: the Seoul Metropolitan region as an overmaturated (or overarching) Fordist region performing the conceptive functions of management, research and development, in which all types of industry (including service industries) tended to be reconcentrated; Kyungsang region as a maturated Fordist region with excutive branches of large conglomerates and with subcontracting firms around them which produced standardized products through the automized production processes in secialized Fordist industries or rationalized traditional industries; and Jeolla and Chungchong regions as newly devloping Fordist regions with newly migrated branches and some subcontracting small firms-in relatively older Fordist industries or partly rationalized traditional industries. From these analyses, it can be argued that the structural adjustment of the Korean industry in the 1980s, which had carried out both through the extensive expansion and the intensive deveiopment, strengthened further uneven regional development process, even though it appears to have reduced apparently the economic and regional disparity by balancing numerically large and small firms and by extending the Fordist industrial space nation-wideiy. And it seems more persuasive to see that the Korean industrial structure in the 1980s maturated the Fordist system of accumulation, but not yet transformed towards the post-Fordist (or the so-called flexible) accumulation system, even though the Korean economy in the 1990s seems to be under a pressure of restructuring towards the latter system.

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Soil Characteristics according to the Geological Condition of Soil Slopes in Landslide Area (산사태지역 토층사면의 지질조건별 토질특성)

  • Kim, Kyeong-Su
    • The Journal of Engineering Geology
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    • v.16 no.4 s.50
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    • pp.359-371
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    • 2006
  • In this study, the soil characteristics are analyzed using the result of various soil tests as an object of the soil layer of natural slopes in landslides areas composed with gneiss, granite, and the tertiary sedimentary rock. To investigate the soil characteristics according to landslide and non landslide areas, soils are sampled from Jangheung, Sangju and Pohang. The landslides at three areas are occurred due to heavy rainfall in same time. The geology of Jangheung area, Sangju area and Pohang area is gneiss, granite, and the tertiary sedimentary rock, respectively. On the basis of the landslide data and the result of soil test, the soil characteristics at the landslide area and the differentiation between landslide area and non landslide area are analyzed. However soil characteristics have a little differentiation to geological condition, the uniformity coefficient and the coefficient of gradation of soils at the landslide area is larger than those of soils at the non landslide area. Also, the proportion of fine particle of soils at the landslide area is higher. The plastic limit of soils sampled from the granite and the sedimentary rock regions is larger than that sampled from the gneiss region. However the liquid limit is irrelevant to the geological condition. Also, the consistency of soils at the landslide area is smaller. The natural moisture content of soils in the sedimentary rock regions is larger than that of the granite and gneiss. It is mainly influenced by mineral composition, soil layer structure, weathering condition, and so on. The soils sampled from landslide area have higher porosity and lower density than those from non landslide area. It means that the soils of landslide area have poor particle size distribution and loose density. Therefore, the terrain slope with poor distribution and loose density is vulnerable to occur in landslides. Also, landslides are occurred in the terrain slope with high permeability. The permeability is mainly influenced by the soil characteristics such as particle size distribution, porosity, particle structure, and the geological origins such as weathering, sedimentary environment. Meanwhile, the shear strength of soils is little difference according to the geological condition. But, the internal friction angle of soils sampled from the landslide area is lower than that of soils from the non landslide area. Therefore, the terrain slope with low internal friction angle is more vulnerable to the landslide.

Genesis and Classification of the Red-Yellow Soils derived from Residuum on Acidic and Intermediate Rocks -II. Songjeong series (산성암(酸性岩) 및 중성암(中性岩)의 잔적층(殘積層)에 발달(發達)한 적황색토(赤黃色土)의 생성(生成) 및 분류(分類) -제(第)II보(報) 송정통(松汀統)에 관(關)하여)

  • Um, Ki Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.2
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    • pp.75-81
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    • 1973
  • The morphological, physical, and chemical properties of Sonjeong series derived from acidic crystalline rocks are presented. Also it deals with the genesis and classification of the Songjeong series. Morphologically these soils have brown to dark brown loam A horizons and yellowish red to red clay loam Bt horizons with moderate, medium subangular blocky structure and thin patchy clay cutans on the ped faces. C horizons are very deep, yellowish red to yellowish brown fine sandy loam or sandy loam with original rock structure. Physically distribution of particle size indicates that clay increases with depth up to argillic horizons but below the argillic horizons clay content decrease. The moisture holding capacity is fairly good in Songjeong soils. Chemically soil reaction is strongly to very strongly acid throughout the profile and content of organic matter is less than 1 per cent except A horizons. Cation exchange capacity ranges from 5 to 9 me/100g of soils and base saturation is less than 35 per cent throughout the profile. The natural fertility of Songjeong soils are usually low. It needs lime, organic matter, and heavy application of fertilizer for the crop land. These soils occur temperate and humid climate under coniferous, deciduous, and mixed forest vegetation. Songjeong soils are classified as Red-Yellow Soils. Characteristically Songjeong soils are similar to Red-Yellow Podzolic soils in the United States but lack of A2 horizons and are quite liket Red-Yellow Soils of the Japan. According to new classification system which is 7th approximation of USDA Songjeong soils can be classified as fine loamy, mesic family of Typic Hapludults and in the FAO/UNESCO project World Soil Map as Orthic Acrisols.

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Improvement of Fatigue Life with Local Reinforcement for Offshore Topside Module during Marine Transportation (해양플랫폼 탑사이드 모듈의 해상 운송 시 국부 보강을 통한 피로 수명 개선에 관한 연구)

  • Jang, Ho-Yun;Seo, Kwang-Cheol;Park, Joo-Shin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.2
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    • pp.387-393
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    • 2021
  • In this study, finite element analysis was performed to evaluate a method of increasing the fatigue life of the pipe connection structure commonly used in the topside structure of offshore platforms. MSC Patran/Nastran, a commercial analysis program, was used, and the critical structural model was selected from the global analysis. To realize the stress concentration phenomenon according to the load, modeling using 8-node solid elements was implemented. The main loads were considered to be two lateral loads and a tensile load on a diagonal pipe. To check the hotspot stress at the main location, a 0.01 mm dummy shell element was applied. After calculating the main stress at the 0.5-t and 1.5-t locations, the stress generated in the weld was estimated through extrapolation. In some sections, this stress was observed to be below the fatigue life that should be satisfied, and reinforcement was required. For reinforcement, a bracket was added to reduce the stress concentration factor where the fatigue life was insufficient without changing the thickness or diameter of the previously designed pipe. Regarding the tensile load, the stress in the bracket toe increased by 23 %, whereas the stress inside and outside of the pipe, which was a problem, decreased by approximately 8 %. Regarding the flexural load, the stress at the bracket toe increased by 3 %, whereas the stress inside and outside of the pipe, which was also a problem, decreased by approximately 48 %. Owing to the new bracket reinforcement, the stress in the bracket toe increased, but the S-N curve itself was better than that of the pipe joint, so it was not a significant problem. The improvement method of fatigue life is expected to be useful; it can efficiently increase the fatigue life while minimizing changes to the initial design.

A Study on the Structural Reinforcement of the Modified Caisson Floating Dock (개조된 케이슨 플로팅 도크의 구조 보강에 대한 연구)

  • Kim, Hong-Jo;Seo, Kwang-Cheol;Park, Joo-Shin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.1
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    • pp.172-178
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    • 2021
  • In the ship repair market, interest in maintenance and repair is steadily increasing due to the reinforcement of prevention of environmental pollution caused by ships and the reinforcement of safety standards for ship structures. By reflecting this effect, the number of requests for repairs by foreign shipping companies increases to repair shipbuilders in the Southwest Sea. However, because most of the repair shipbuilders in the southwestern area are small and medium-sized companies, it is difficult to lead to the integrated synergy effect of the repair shipbuilding companies. Moreover, the infrastructure is not integrated; hence, using the infrastructure jointly is a challenge, which acts as an obstacle to the activation of the repair shipbuilding industry. Floating docks are indispensable to operating the repair shipbuilding business; in addition, most of them are operated through renovation/repair after importing aging caisson docks from overseas. However, their service life is more than 30 years; additionally, there is no structure inspection standard. Therefore, it is vulnerable to the safety field. In this study, the finite element analysis program of ANSYS was used to evaluate the structural safety of the modified caisson dock and obtain additional structural reinforcement schemes to solve the derived problems. For the floating docks, there are classification regulations; however, concerning structural strength, the regulations are insufficient, and the applicability is inferior. These insufficient evaluation areas were supplemented through a detailed structural FE-analysis. The reinforcement plan was decided by reinforcing the pontoon deck and reinforcement of the side tank, considering the characteristics of the repair shipyard condition. The final plan was selected to reinforce the side wing tank through the structural analysis of the decision; in addition, the actual structure was fabricated to reflect the reinforcement plan. Our results can be used as reference data for improving the structural strength of similar facilities; we believe that the optimal solution can be found quickly if this method is used during renovation/repair.

The Limnological Survey of Major Lakes in Korea (4): Lake Juam (국내 주요 호수의 육수학적 조사(4) : 주암호)

  • Kim, Bom-Chul;Heo, Woo-Myung;Lim, Byung-Jin;Hwang, Gil-Son;Choi, Kwang-Soon;Choi, Jong-Soo;Park, Ju-Hyun
    • Korean Journal of Ecology and Environment
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    • v.34 no.1 s.93
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    • pp.30-44
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    • 2001
  • In this study limnological characteristics of Lake Juam was surveyed from June 1993 to May 1994 in order to provides important information regarding water resources. Secchi disc transparency, epilimnetic chlorophyll a (chi-a), total nitrogen (TN), total phosphorus (TP) concentration and primary productivity were in the range of $2.0{\sim}4.5\;m$, $0.9{\sim}13.6\;mgChl/m^3$, 0.78$\{sim}$2.32 mgN/l, $11{\sim}56\;mgP/m^3$, $270{\sim}2.160\;mgCm^{-2}\;day^{-1}$, respectively. On the basis of TP, Chl-a and Secchi disc depth, the trophic state of Lake Juam can be classied as mesotrophic lake. The phosphorus inputs from non-point sources are concentrated in heavy rain episodes during the monsoon season. As a result, phosphorus concentration are higher in summer than in winter. TP loading from the watershed were estimated to be $0.9\;gPm^{-2}yr^{-1}$, which correspond to a boundary of the critical loading ($1.0\;gPm^{-2}yr^{-1}$) for eutrophication. From the results of the algal assay, both phosphous and nitrogen act as limiting nutrients in algal growth. The seasonal succession of phytoplankton community structure in Lake Juam was similar to that observed in other temperate lakes. Diatoms (Asterionella formosa and Aulacoseira granulate var. angustissima)fujacofeira BraHuJafa uar. aHgusHrsiaia) weredominant in spring and winter, cyanobacteria) were dominant in warm season. The organic carbon, nitrogen and phosphorus content of lake sediment were $9.5{\sim}14.0\;mgC/g$, $1.01{\sim}1.82\;mgN/g$ and $0.51{\sim}0.65\;mgP/g$, respectively. The allochthonous organic carbon loading from the watershed and autochthonous organic carbon loading by primary production of phytoplankton were determined to be 1,122 tC/yr and 6,718 tC/yr, respectively. To prevent eutrophication of Lake Juam, nutrient management of watershed should be focus on reduction of fertilizer application, proper treatment of manure, and conservation of topsoil as well as point source.

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