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A Study on the Landscape Characteristics of 16 Sceneries of Hahoe Village, Represented in "Hahoe 16 Sceneries" and "Picture Describing Hahwae Village" ("화회십육경(河回十六景)"과 "하외낙강상하일대도(河隈洛江上下一帶圖)"를 통해 본 하회16경의 경관상)

  • Rho, Jae-Hyun;Lee, Hyun-Woo
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.1
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    • pp.48-58
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    • 2013
  • The results of this research to study forms, structure, changes, symbolic meanings of 16 Hahoe sceneries through analyses of "Hahwaesipyukgyeong" and "Hahwaenakgangsanghaildaedo" are as belows. The coherence of headword is not discovered in 16 Hahoe sceneries, but based on various variables and sense dependence, endemicity with original natural scenes, human's life and phenomena of riverside village are spread in 3km viewing areas within 200m from Gyeonamjeongsa(謙巖精舍) and Okyeonjeongsa(玉淵精舍). As the viewing points of Gyeonam and Okyeonjeongsa are symmetrically facing and separately independent, while viewing angles do not intersect at Wonjijeongsa (遠志精舍) and Binyeonjeongsa(賓淵精舍) because of Buyongdae(芙蓉臺), and crating each independent viewing area, we can see 16 Hahoe sceneries are perfect views by supplementing Gyeonam and Okyeon Jeongsa, as well as points of views from Wonji and Binyeonjeongsa. Meanwhile, as the view point of 16 Hahoe sceneries, Gyeomam, Okyeon, Binyeon, and Wonji Jeongsa are clearly described, and 12 natural sceneries, which are Hwasan(花山), Ipam(立巖), Maam(馬巖), Jando(棧道), Bangi(盤磯), Hoengju(橫舟), and Honggyo(虹橋), among landscape elements of 16 Hahoe sceneries that can be expressed on canvas in the Haoedo are realistically described, there is high possibility that Haoedo is the 'Mental Stroll about Nature(臥遊) of 16 Hahoe sceneries. The belted forest surrounding the village in the painting is assumed to be an erosion control forest, and considering row-expressed trees, the south belted forest may be a different broad-leaved forest from current Mansongjeong(萬松亭) pine forest. In 16 Hahoe sceneries, there is Neo-confucianism tendency, which connects the nature and human life, and moreover prioritize human life than the nature. Especially as seen in the 'Choljae(拙齋)', the pen name of 16 Hahoe sceneries' author park, the 16 Hahoe scenery poet suggests 'Beauty of Jolbak(拙撲美)' based on the simple life that upright classical scholars pursued as the basic emotion. The thinking system shown in the poet is interpreted as Neo-confucianism category including one's sense and emotion depended on natural features or phenomena. Ultimately, 16 Hahoe sceneries are landscape that reflects moral world views of Confucianism scholars who wanted to express ideal thoughts based on natural features and phenomena in reality at Jeongsa in Buyongdae and Hahoe Village.

Water Quality Improvement of Stagnant Water using an Upflow Activated Carbon Biofilm Process and Microbial Community Analysis (상향류 활성탄 생물막 공정을 이용한 정체 수역 수질 개선 및 공정 내 미생물 군집 해석)

  • Oh, Yu-Mi;Lee, Jae-Ho;Park, Jeung-Jin;Choi, Gi-Choong;Park, Tae-Joo;Lee, Tae-Ho
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.1
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    • pp.23-32
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    • 2010
  • The capacity of natural purification was limited by the interruption of natural flow and the problems such as eutrophication were occurred by nutritive salts accumulation in stagnant stream. Moreover, the inflow of non-point sources causes non-degradable materials to increase in stagnant stream. In this study, an upflow biological activated carbon (BAC) biofilm process comprised of anoxic, aerobic 1, and aerobic 2 reactors were introduced for treatment of stagnant stream and SS, $BOD_5$, $COD_{Mn}$, $COD_{Cr}$, TN, and TP were monitored in the upflow BAC biofilm reactors with continuous cycling. In order to simulate stagnant stream, the lake water of amusement park and golf course were stored as influent in a tank of $2m^3$ and hydraulic retention time (HRT) was changed into 6, 4, and 2 hours. At HRT 4hr and the lake water of amusement park as influent, the removal efficiencies of SS, $BOD_5$, $COD_{Mn}$, $COD_{Cr}$, TN, and TP showed the best water quality improvement and were 69.8, 83.0, 91.3, 74.1, 74.7, and 88.9%, respectively. At HRT 4hr and the lake water of golf course as influent, the removal efficiencies of SS, $BOD_5$, $COD_{Mn}$, $COD_{Cr}$, TN and TP were 78.5, 78.0, 80.2, 74.9, 55.6 and 97.5%, respectively. As the results of polymerase chain reaction - denaturing gel gradient electrophoresis (PCR-DGGE), microbial community was different depending on influent type. Fluorescence in situ hybridization (FISH) showed that nitrifying bacteria was dominant at HRT 4 hr. The biomass amount and microbial activities by INT-DHA test were not decrease even at lower HRT condition. In this study, the upflow BAC biofilm process would be considered to the water quality improvement of stagnant stream.

A Destructive Method in the Connection of the Algorithm and Design in the Digital media - Centered on the Rapid Prototyping Systems of Product Design - (디지털미디어 환경(環境)에서 디자인 특성(特性)에 관한 연구(硏究) - 실내제품(室內製品) 디자인을 중심으로 -)

  • Kim Seok-Hwa
    • Journal of Science of Art and Design
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    • v.5
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    • pp.87-129
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    • 2003
  • The purpose of this thesis is to propose a new concept of design of the 21st century, on the basis of the study on the general signification of the structures and the signs of industrial product design, by examining the difference between modern and post-modern design, which is expected to lead the users to different design practice and interpretation of it. The starting point of this study is the different styles and patterns of 'Gestalt' in the post-modern design of the late 20th century from modern design - the factor of determination in industrial product design. That is to say, unlike functional and rational styles of modern product design, the late 20th century is based upon the pluralism characterized by complexity, synthetic and decorativeness. So far, most of the previous studies on design seem to have excluded visual aspects and usability, focused only on effective communication of design phenomena. These partial studies on design, blinded by phenomenal aspects, have resulted in failure to discover a principle of fundamental system. However, design varies according to the times; and the transformation of design is reflected in Design Pragnanz to constitute a new text of design. Therefore, it can be argued that Design Pragnanz serves as an essential factor under influence of the significance of text. In this thesis, therefore, I delve into analysis of the 20th century product design, in the light of Gestalt theory and Design Pragnanz, which have been functioning as the principle of the past design. For this study, I attempted to discover the fundamental elements in modern and post-modern designs, and to examine the formal structure of product design, the users' aesthetic preference and its semantics, from the integrative viewpoint. Also, with reference to history and theory of design my emphasis is more on fundamental visual phenomena than on structural analysis or process of visualization in product design, in order to examine the formal properties of modern and post-modern designs. Firstly, In Chapter 1, 'Issues and Background of the Study', I investigated the Gestalt theory and Design Pragnanz, on the premise of formal distinction between modern and post-modern designs. These theories are founded upon the discussion on visual perception of Gestalt in Germany in 1910's, in pursuit of the principle of perception centered around visual perception of human beings. In Chapter 2, I dealt with functionalism of modern design, as an advance preparation for the further study on the product design of the late 20th century. First of all, in Chapter 2-1, I examined the tendency of modern design focused on functionalism, which can be exemplified by the famous statement 'Form follows function'. Excluding all unessential elements in design - for example, decoration, this tendency has attained the position of the international style based on the spirit of Bauhause - universality and regularity - in search of geometric order, standardization and rationalization. In Chapter 2-2, I investigated the anthropological viewpoint that modern design started representing culture in a symbolic way including overall aspects of the society - politics, economics and ethics, and its criticism on functionalist design that aesthetic value is missing in exchange of excessive simplicity in style. Moreover, I examined the pluralist phenomena in post-modern design such as kitsch, eclecticism, reactionism, hi-tech and digital design, breaking away from functionalist purism of modern design. In Chapter 3, I analyzed Gestalt Pragnanz in design in a practical way, against the background of design trends. To begin with, I selected mass product design among those for the 20th century products as a target of analysis, highlighting representative styles in each category of the products. For this analysis, I adopted the theory of J. M Lehnhardt, who gradated in percentage the aesthetic and semantic levels of Pragnantz in design expression, and that of J. K. Grutter, who expressed it in a formula of M = O : C. I also employed eight units of dichotomies, according to the G. D. Birkhoff's aesthetic criteria, for the purpose of scientific classification of the degree of order and complexity in design; and I analyzed phenomenal aspects of design form represented in each unit. For Chapter 4, I executed a questionnaire about semiological phenomena of Design Pragnanz with 28 units of antonymous adjectives, based upon the research in the previous chapter. Then, I analyzed the process of signification of Design Pragnanz, founded on this research. Furthermore, the interpretation of the analysis served as an explanation to preference, through systematic analysis of Gestalt and Design Pragnanz in product design of the late 20th century. In Chapter 5, I determined the position of Design Pragnanz by integrating the analyses of Gestalt and Pragnanz in modern and post-modern designs In this process, 1 revealed the difference of each Design Pragnanz in formal respect, in order to suggest a vision of the future as a result, which will provide systemic and structural stimulation to current design.

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Recruitment and Succession of Riparian Vegetation in Alluvial River Regulated by Upstream Dams - Focused on the Nakdong River Downstream Andong and Imha Dams - (댐 하류 충적하천에서 식생이입 및 천이 - 낙동강 안동/임하 댐 하류하천을 중심으로 -)

  • Woo, Hyo-Seop;Park, Moon-Hyung;Cho, Kang-Hyun;Cho, Hyung-Jin;Chung, Sang-Joon
    • Journal of Korea Water Resources Association
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    • v.43 no.5
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    • pp.455-469
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    • 2010
  • Changes of geomorphology in alluvial river and vegetation recruitment on its floodplain downstream from dams are investigated both qualitatively and quantitatively focusing on the downstream of Andong dam and Imha dam on the Nakdong River. Results of the analyses of river morphology and bed material in the study site show a general trend of riverbed degradation with a max scour of 3 m and bed material coarsening from pre-dam value of 1.5 mm in D50 to post-dam value of 2.5 mm. Decrease in bed shear stress due to the decrease in flood discharge have caused vegetation recruitment on the once-naked sandbars. As result, the ratio of area of vegetated bars over total area of bars has drastically changed from only 7% in 1971 before the Andong dam (constructed in 1976) to 25% after it, and increased to 43% only three year after the Imha dam (constructed in 1992) and eventually to 74% by 2005. Analysis of the vegetation succession at Wicjeol subreach, one of the three subreaches selected in this study for detailed investigation, has clearly shown a succession of vegetation on once-naked sand bars to a pioneering stage, reed and grass stage, willow shrub and eventually to willow tree stages. At the second subreach selected, two large point bars in front of Hahoe Village seem to have maintained their sand surfaces without a signifiant vegetation recruitment until 2005. The sand bars, however, seem to have been invaded by vegetation recently, which warns river managers to have a countermeasure to protect the sand bars from vegetation invasion in order to conserve them for the historical village of Hahoe. On the other hand, recruitment and establishment of vegetation on the sand bars by artificial disturbance of the river, such as damming, can create an unique habitat of backmarsh in the sandy river, as shown in the case of Gudam Wetland, and may increase the biodiversity as compared with relatively monotonous sand bars. Last, the premise in this study that decrease in flood discharge due to upstream dams and decrease in bed shear stress can induce vegetation recruitment on the naked sand bars in the river has been verified with the analyses of the distribution of dimensionless bed shear stress along the selected cross section in each subreach.

A Study on Environmental Standards of School Building (교사환경기준에 관한 연구)

  • Hong, Seok-Pyo;Park, Young-Soo
    • The Journal of Korean Society for School & Community Health Education
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    • v.1 no.1
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    • pp.11-43
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    • 2000
  • The purpose of this study was, through analyzing the previous researches, to grasp the present status of environment of school building(ESB), research the sundry records of each element and, through comparative analysis of the standard of ESB in Korea, the United States, and Japan, select the normative standard of ESB, to clarify the point at issue presented in Regulation of Construction & facility Management for Elementary and and Secondary School in Korea, and to suggest an alternative preliminary standard of ESB. To carry out a research for this purpose, these were required: 1. to investigate the existing present status of ESB, 2. to make a comparative analysis of the standard of ESB in each country, 3. to suggest the normative standard of preliminary standard of ESB, 4. to analyze the controversial points of the standard of ESB in Korea, 5. to suggest an alternative preliminary standard of ESB. The conclusions were as follows: 1. Putting, through analyzing the previous researches, the existing present status of ESB together, it seemed that lighting environment, indoor air environment and noise environment were all in poor conditions. 2. In the result of a comparative analysis of the standard of ESB in Korea, Japan and the United States, in Korea the factors of each lighting and indoor air environment were not presented properly, in Japan, in lighting environment aspect, the standard on natural lighting and the factors on brightness were not presented., and in the USA the essential factors of each environment were throughly presented. In the comparison of the standards on each factor, Korea showed that the standard level presented was less properly prescribed than those of the USA and Japan but it also showed that the standard levels prescribed in the USA and in Japan were mostly similar to the standard levels in records investigated. 3. With the result of the normative standard selection on School Builiding environment factor of prescribed in this study, the controversial points of the standard of ESB in Korea were analyzed and the result was utilized to suggest new preliminary standard of ESB. 4. As the result of the analysis of the controversial points of the standard of ESB in Korea, it was found that the standard of ESB in Korea should be established on a basis of School Health Act and be concretely presented in School Health Regulation and School Health Rule. The factors of each environment was improperly presented in the existing standard of ESB in Korea. Moreover the standard of them was inferior to that of the records investigated and those of in the USA and in Japan and it also showed that the standard of it in Korea was improper to maintain Comfortable Learning Environment. 5. A suggested preliminary standard of ESB acquired through above study as follows: 1) In this study a new kind of preliminary standard of ESB is divided into lighting environment, indoor air environment, noise environment, odor environment and for above classification, reasonable factor and standard should be established and the controling way on each standard and countermeasures against it should be considered. 2) In lighting environment, the factors of natural lighting are divided into daylight rate, brightness, glare. In the standard on each factor, daylight rate should secure 5% of a mean daylight rate and 2% of a minimum daylight rate, brightness ratio of maximum illumination to minimum illumination should be under 10:1, and in glare there should not be an occurrence factor from a reflector outside of the classroom. And the factors of unnatural lighting are illumination, brightness, and glare. In the standard on each factor, illumination should be 750 lux or more, brightness ratio should be under 3 to 1, and glare should not occur. And Optimal reflection rate(%) of Colors and Facilities of Classroom which influences lighting environment should be considered. 3) In indoor air environment factors, thermal factors are divided into (1) room temperature, (2) relative humidity, (3) room air movement, (4) radiation heat, and harmful gases (5) CO, (6) $CO_2$ that are proceeded from using the heating fuel such as oval briquettes, firewood, charcoal being used in most of the classroom, and finally (7) dust. In the standard on each factor, the next are necessary; room temperature: $16^{\circ}C{\sim}26^{\circ}C$(summer : $E.T18.9{\sim}23.8^{\circ}C$, winter: $E.T16.7{\sim}21.7^{\circ}C$), relative humidity: $30{\sim}80%$, room air movement: under 0.5m/sec, radiation heat: under $5^{\circ}C$ gap between dry-bulb temperature and wet-bulb temperature, below 1000 ppm of ca and below 10ppm of $CO_2$, dust: below 0.10 $mg/m^3$ of Volume of dust in indoor air, and ventilation standard($CO_2$) for purification of indoor air : once/6 min.(about 7 times/40 min.) in an airtight classroom. 4) In the standard on noise environment, noise level should be under 40 dB(A) and the noise measuring way and the countermeasures against it should be considered. 5) In the standard on odor environment, odor level under Physical Method should be under 2 degrees, and the inspecting way and the countermeasures against it should be considered.

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Material and Behavior Characteristics of Lightweight Embankment for Road Constructed on Soft Ground (연약지반에 시공된 도로용 경량성토체의 재료 및 거동특성)

  • Yea, Geu-Guwen;Lee, Yong-Jae;Kim, Hong-Yeon;Yoon, Gil-Lim;Han, Sang-Hyun
    • Journal of the Korean Geosynthetics Society
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    • v.17 no.2
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    • pp.41-49
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    • 2018
  • The purpose of this study is to fabricate a full scale road embankment using lightweight air foamed soil as a soil material on soft ground and to investigate its material characteristics and behavior in order to promote dredged soil utilization and minimize ground improvement. As a result of the laboratory test of the onsite mixed samples, the total unit weight of the specimens decreased almost linearly until curing 28 days. In particular, the total unit weight after 28 days of curing was reduced to about 81% of the slurry state before curing, which will be useful in the formulation of similar native soil materials in the future. The unconfined compressive strength began to decrease with the 14th day of curing as shown in the previous study. When the cement content is increased, the strength decreases sharply at a small strain change after the occurrence of the maximum compressive strength, and the maximum strength is exhibited in a range of a smaller axial strain than normal range. The settlement at the surface layer of the ground due to the lightweight embankment was about 1 / 2.75 of the soil embankment and was in agreement with the unit weight ratio (1 / 2.7) of the embankment materials. This indicates the cause and effect of the settlement due to the difference in self weight of the embankments. Also, the difference in settlement between soil and lightweight embankment increased with increasing depth. This shows that the difference in the point at which the settlement is terminated is clear. The ground horizontal displacement under the lightweight embankment was about 15~20% smaller than that of the soil embankment and the depth of occurrence was also 4.5~5.0m shallower in the lightweight embankment.

Thermal Conductivity and Pore Characteristics of Low-Temperature Sintered Lightweight Aggregates Mode from Waste Glass and Bottom Ash (바텀애쉬와 폐유리를 사용하여 제조한 저온소성 경량골재의 열전도율과 기공특성)

  • Lee, Han-Baek;Ji, Suk-Won;Seo, Chee-Ho
    • Journal of the Korea Concrete Institute
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    • v.22 no.6
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    • pp.851-858
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    • 2010
  • In this study, waste glass and bottom ash were used as basic materials in order to secure a recycling technology of by-products which was mostly discarded and reclaimed. In addition, because softening point of waste glass is less than $700^{\circ}C$ and bottom ash includes combustible material, it was possible to manufacture low-temperature sintering lightweight aggregates for energy saving at $800{\sim}900^{\circ}C$ that it is as much as 20~30% lower than sintering temperature of existing lightweight aggregates. Thermal conductivity of newly-developed lightweight aggregates was 0.056~0.105W/m. K and its porosity was 40.36~84.89%. A coefficient of correlation between thermal conductivity and porosity was -0.97, it showed very high negative correlationship. With this, we were able to verify that porosity is key factor to affect thermal conductivity. Microstructure of lightweight aggregates by $CaCO_3$ content and replacement ratio of bottom ash in the variation of temperature were that $CaCO_3$ content increased along with pore size while replacement ratio of bottom ash increased as pore size decreased. Specially, most pores were open pore instead of closed pore of globular shape when replacement ratio of bottom ash was 30%, and pore size was small about 1/10~1/5 as compared with case in bottom ash 0~20%. In addition, open pore shapes were remarkably more irregular form of open pore in $900^{\circ}C$ than $700^{\circ}C$ or $800^{\circ}C$ when replacement ratio of bottom ash was 30%. We reasoned hereby that these results will influence on absorption increase, strength and thermal conductivity decrease of lightweight aggregates.

Evaluation of the Clinical Usefulness of the Xeniss Rapid TB kit for the Diagnosis of Tuberculosis (결핵진단에서 Xeniss Rapid TB kit의 임상적 유용성)

  • Park, Seung-Kyu;Lee, Woo-Chul;Hwang, Soo-Hee;Kwon, Eun-Si;Lee, Hung-Soon;Lee, Duk-Hyoung
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.4
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    • pp.389-400
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    • 2002
  • Background : The rapid diagnostic tests for tuberculosis are needed to facilitate early treatment of tuberculosis and prevention of Mycobacterium tuberculosis transmission. The Xeniss Rapid TB kit is a rapid, card-based immunochromatographic test for the detection of antibodies directed against M. tuberculosis antigens including antigen 5(38-kDa antigen). The objective of this study was to evaluate the performance of the Xeniss Rapid TB kit for the diagnosis of active tuberculosis with serums from patients, asymptomatic healthy and close contact controls. Methods : 188 patients with active tuberculosis were tested; 177 with pulmonary tuberculosis(18 with combined pleurisy), and 11 with extrapulmonary tuberculosis. The control groups were composed of 82 close contacts and 57 healthy adults. Study subject were drawn from one national tuberculosis hospital for patients and close contacts, and another private hospital for healthy adults in Masan city, Korea. The Xeniss Rapid TB kit(Xeniss Life Science Co., Ltd., Seoul, Korea) was evaluated by using serum samples according to the instructions of the manufacturer by an investigator masked to the clinical and microbiological status of the study subjects. Results : The diagnostic sensitivity of the Xeniss Rapid TB kit was 73.9% in patients and specificities were 73.2% and 93.0% in close contact and healthy adults respectively. The positive predictive value in patients was 84.2% and the negative predictive value in controls was 85.8%. Conclusion : This study shows that the Xeniss Rapid TB test is a simple and fast method to diagnose active TB. The results of the sensitivity and specificites suggest that serodiagnosis using this point of care testing(POCT) device would be valuable and advantageous for screening tuberculosis in the clinical field.

Influence of the Composition and Concentration of Fertilizer Solution on Growth and Nutrient Uptake of 'Maehyang' Strawberry during Vegetative Growth (비료의 조성 및 농도가 영양생장 중인 '매향' 딸기의 생장, 양분흡수 및 근권환경 변화에 미치는 영향)

  • Jang, Hyun Ho;Lee, Hee Su;Lee, Chiwon W.;Choi, Jong Myung
    • Horticultural Science & Technology
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    • v.32 no.4
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    • pp.484-492
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    • 2014
  • We quantified the effects of the composition and concentration of fertilizer solutions on the growth and nutrient uptake of 'Maehyang' strawberry at the vegetative growth stage. Acid fertilizer (AF), neutral fertilizer (NF), and basic fertilizer (BF) with concentrations of 100 or $200mg{\cdot}L^{-1}$ based on N, were formulated and applied during the 100 days after transplanting, at which point crop growth and tissue nutrient contents were analyzed. The soil solutions were sampled every two weeks to measure the pH, EC and nutrient concentrations. BF was a more effective fertilizer compared to AF and NF for growth of 'Maehyang' strawberry when fertilizer concentrations were controlled to $100mg{\cdot}L^{-1}$. By contrast, the fresh and dry weights were greatest in the NF treatment when fertilizer concentrations were controlled to $200mg{\cdot}L^{-1}$. The tissue contents of N, P, and Na were 2.20, 0.51 and 0.10%, respectively, in the NF 200 treatment, and these were the highest among all treatments tested. The highest contents of K, Ca and Mg were 2.60% in AF 200, 0.95% in BF 200 and 0.45% in BF 100, respectively. During the fertilization period, the highest and lowest pHs were 6.13 in BF 100 and 4.92 in AF 200. The lowest EC was $1.376dS{\cdot}m^{-1}$ in BF 100 and the highest was $4.936dS{\cdot}m^{-1}$ in NF 200 treatments. The highest $NH_4{^+}$ concentrations in the soil solution occurred during the AF 200 treatment, followed by those with NF 200 and AF 100. When fertilizer concentrations were equal, AF treatment gave rise to the highest $Ca^{+2}$ and $Mg^{+2}$ concentrations, followed by NF and BF, until day 84 of fertilization. The BF treatments had the highest $NO_3{^-}$ concentrations followed by NF and AF. The trends for $PO_4^{-3}$ concentrations were similar in all fertilizer treatments when the fertilizer concentrations were equal. The above results indicate that neutral and basic fertilizers were most effective to promote 'Maehyang' strawberry growth when fertilizer solutions were controlled to low or high concentrations, respectively. These findings are useful for planning fertilization programs for vegetative propagation of 'Maehyang' strawberry.

A study for detection of melt flow zone about polyethylene butt fusion joints (폴리에틸렌 배관 버트융착부 열용융거리 측정에 대한 연구)

  • Kil, Seonghee;Kim, Younggu;Jo, NYoungdo;Lee, Yeonjae
    • Journal of Energy Engineering
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    • v.25 no.4
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    • pp.103-109
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    • 2016
  • Polyethylene pipes has useful benefits which are anti-corrosive and flexible material, so it is used to gas pipes but also class 3 water pipes of nuclear power plant, process pipes of petrochemical plant and chemical plant. So the usage of polyethylene pipes is widely increased. But it has been limited for the usage of polyethylene, because it can not be directly detected to fusion joints by using non destructive evaluation. Polyethylene pipes are connected by two methods, one is butt fusion and the other is electrofusion. Butt fusion is widely used to connecting the pipes. It is proposed to method for determining the reliability of joints in this study that is detection of the melt flow zone at fusion joints. In this study, middle density polyethylene is used, outside diameter of the test specimen is 225mm and thickness is 20.5mm. Speed of ultrasonic of this test specimen is 2,200m/s. Test specimens were fabricated by varying the heating time which means from 0% to 130% applying time through heating plate to polyethylene for detecting melt flow zone. Also 4 additional test specimens were made, one was made that not scrapping attached surface of pipes but applying 100% of the proper heating time and the others were made to include of soil, gravel and vinly tape paper at fusion joints, that were also applied 100% of proper heating time. Ultrasonic testing to measure the melt flow zone of 20 test specimens was conducted by using 3.5MHz and 5.0MHz ultrasonic probes and melt flow zone measuring was conducted to three times at different point to one specimen. To differentiate the melt flow zone signal, post image processing was equally conducted to all test results and image levels, contrast, sharpen, threshold were adopted to all teat results and the test results were displayed gray scale. From the results, for the shorter heating times the reflection area of multiple echo have been increased, so the data was obtained from the position where it can be eliminated as much as possible. At 80% of proper heating time(168 sec.), the signal of melt flow zone was obtained clearly, so measuring could be conducted. From 7% of proper heating time(15 sec.) to shorter heating times. we could not obtain the signal because test specimen was not fused. From the result, we can verify that measuring of melt flow zone by using phased array ultrasonic imaging method is possible. And we can verify to complete and incomplete butt fusion by measuring the melt flow zone.