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Reduction of the Nitrogen in the Secondary Effluent by the Hybrid Sequential Aerobic-Anoxic Natural System (자연현상을 이용한 질산화-탈질공정에 의한 하수처리장 유출수의 질소제거)

  • Kim, Young-Chul;Chung, Paul-Gene;An, Ik-Sung
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.3
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    • pp.323-329
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    • 2005
  • In this paper, performance of a hybrid sequential aerobic-anaerobic natural system was investigated. Continuous aerobic and anoxic conditions were created by alternatively placing waste stabilization pond (WSP) and wale. hyacinth pond (WHP). Two pilot-scale treatment lines were built and operated; The first consists of WSP integrated with WHP and the second of WSP connected with Dark Pond(DP), namely control system ponds which were used to examine the effects of water hyacinth on nitrification and de-nitrification. The overall performance in nitrogen was 86% reduction in WSP-WHP and 36% in WSP-control pond system. Nitrogen was mostly removed by nitrification and de-nitrification which simultaneously occurred in the same water hyacinth ponds. For the de-nitrification, benthic layer was found out to be adequate support as a carbon source. In addition, WSP-WHP system was very effective in reducing phosphorus. Overall P removal efficiency in WSP-WHP is 81%, while it is only 16% in WSP-control. difference in phosphorus reduction between those two systems is thought to be caused by the plants and probably their roots producing extra-cellular materials, but these aspects need to be further studied.

Preparation and Characterization of Surface Modified Mica by Microwave-enhanced Wet Etching (마이크로웨이브로 증폭된 습식 에칭에 의한 표면 개질 마이카의 제조와 특성)

  • Jeon, Sang-Hoon;Kwon, Sun-Sang;Kim, Duck-Hee;Shim, Min-Kyung;Choi, Young-Jin;Han, Sang-Hoon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.4
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    • pp.269-274
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    • 2008
  • In this study we successfully altered the structural characteristics of the mica surface and were able to control oil-absorption by using the microwave enhanced etching (MEE) technique, which has originally been used in semiconductor industry. When microwave energy is applied to the mica, the surface of the mica is etched in a few minutes. As the result of etching, oil-absorption of the mica was enhanced and surface whiteness was improved by modifying the silicon dioxide layer. Additionally, the high whiteness was maintained even though the etched mica absorbed the sebum or sweat. The surface modification of mica was performed by microwave irradiation after the treatment of hydrofluoric acid. The degree of etching was regulated by acid concentration, irradiation time, the amount of energy and slurry concentration. The surface morphology of the etched mica appears to be the shape of the 'Moon'. The characteristics of surface area and roughness were examined by Brunauer-Emmett-Teller (BET) surface area analysis, atomic force microscopy (AFM), scanning electron microscopy (SEM), spectrophotometer and goniophotometer.

A Study on Deflection Characteristics of Plywood for Wood Based Flooring by Veneer Composition (마루판용 합판의 단판 구성요소에 따른 변형 특성에 관한 연구)

  • Pi, Duck-Won;Kang, Seog Goo
    • Journal of the Korean Wood Science and Technology
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    • v.41 no.1
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    • pp.42-50
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    • 2013
  • Since 1990's, a plywood for flooring base has gotten customers' demand. Costs of raw material and production increased because of changed environment of industry. Tropical timber such as Red Meranti (Shorea acuminate) used for raw material of the floor has been depleting beside countries in South Eastern Asia changed species of afforestation. As a result, it gets hard to secure good quality of raw material for plywood. Moreover plywood price is increased suddenly after earthquake in Japan. Eucalyptus (Eucalyptus globulus) in china has been using for raw material as a countermeasure of changed environment of industry. In this study, possibility of using flooring consisted of Eucalyptus veneer as crossband layers was checked by deflection experiments. Flooring consisted of Red Meranti was used for comparison. Two factors which impact on deflection are a type of density gradient and density difference between Long-grain veneer and Short-grain veneer. Red Meranti samples are M type of density gradient on the other hand Eucalyptus samples are W type of density gradient. The more samples have high density difference, the more deformation was checked. A sample which has big density difference between core and cross bands layer warp more also deform. Flooring was deformed smaller than plywood and samples which have big density difference was deformed more.

Long-term Precipitation Prediction with Icosahedral-hexagonal Gridpoint Model GME (Icosahedral-Hexagonal 격자 체계의 전구 모형 GME를 이용한 장기 강수량 예측)

  • Woo, Su-Min;Oh, Jai-Ho;Koh, A-Ra;Majewski, Detlev
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.2207-2211
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    • 2008
  • 한반도 및 동아시아의 여름철은 장마와 태풍으로 인한 집중호우의 발생으로 많은 피해를 입는다. 따라서 여름철에 나타나는 이러한 집중호우가 나타나는 지역, 시기, 기간, 그리고 강수량 등을 예측하는 것은 매우 중요하다. 특히, 효율적인 수자원 관리를 위하여 이러한 예측은 매우 중요한데, 단기적으로 정확하고 신속하게 강수를 예측하는 것도 중요하지만, 장기적으로 계절 강수, 특히 여름철의 장마 또는 우기의 시기와 강수량과 태풍 발생의 시기 등을 미리 예측하여 이에 따른 집중 호우의 발생 지역, 기간, 강수량을 예측하여 사전에 대비하는 것도 매우 중요하다. 특히, 최근에는 6,7월 장마에 의한 집중 호우의 영향보다도 8월에 강수량이 높아지고 있는 경향을 보이므로 강수량의 장기적 경향의 파악이 매우 중요하다. 장기 기후를 예측하는 데는 과거 자료를 이용한 통계 방법도 유용하지만 최근에는 AOGCM (Atmospheric Oceanic General Circulation Model)을 이용한 연구가 활발하게 이루어지고 있다. 하지만 강수와 같이 지역적으로 나타나는 현상은 저해상도의 AOGCM으로는 유용한 정보를 제공하기가 어려움이 따른다. 따라서 본 연구에서는 전구를 삼각형으로 된 20면체로 격자화 시켜 모든 격자의 크기가 거의 동일하고, 해상도 조절이 가능한 Geodesic 격자를 활용한 GME 모델을 사용하였다. GME 모델은 icosahedral-hexagonal grid 격자 체계를 가진 독일 기상청(Deutscher Wetterdient)에서 현업으로 사용 중인 모델이다. 본 연구에서는 수직/수평 해상도를 40km/40layers로 하여 GME 모델을 수행하였으며, 일간격의 장기 기후 자료를 생산하였다. 사용된 초기자료로는 ECMWF (European Centre for Medium Range Weather Forecasts) 자료이며, 경계 자료로는 ERA Climatology의 최근 30년간의 SST (Sea Surface Temperature) 평균 자료를 이용하여 규준 실험(Control Run), 즉, climatology 자료를 생산하였으며, persistent SST 아노말리와 ERA Climatology의 최근 30년간의 SST 자료를 이용하여 내삽 과정을 거친 SST forcing을 주어서 예측 실험(Prediction Run)을 통하여 모의 자료를 생산하였다. 특히, 규준 실험에서는 수치 모델이 가지는 불확실성을 줄이고 예보 정확도를 향상시키기 위하여 각각의 실험은 초기자료를 달리한 앙상블 모의실험을 수행하였다. 장기 모의 3개월을 위하여 모의 기간 1달 전부터 모의를 수행하여, 첫 1달은 모델의 spin-up 시간으로 분석에서 제외 하였다. 생산된 Climatology 자료와 Prediction 자료를 비교하여 아노말리와 Category 분석을 실시하여 한반도 및 동아시아 지역의 강수(Precipitation)를 중심으로 기압장(Pressure), 온도(2m Temperature) 위주로 분석하였다. 이러한 예측된 매 계절의 전망 자료 중에서도 수자원 분야에서 관심이 집중되는 여름철에 초점을 맞추어 실제 관측 자료와 비교하여 GME 모델의 계절 모의 예측성 성능을 분석하여 평가하고 다가올 여름철의 강수량의 장기 변화를 모의하고자 하였다.

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Study on Nutrient Balance in Paddy Field of Fluvio-Marine Deposit (하해혼성(河海混成) 논토양(土壤)의 양분수지(養分收支)에 관한 연구)

  • Yoo, Chul-Hyun;Yang, Chang-Hyu;Kang, Seung-Weon;Han, Sang-Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.35 no.5
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    • pp.253-263
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    • 2002
  • To test for the effect of applied fertilizer and nutrients on uptake and transport for paddy rice, two paddy field trials were conducted with Dongjinbyeo in degenerated salt paddy field of Jeonbuk series from 1999 to 2000. After experiment, soil acidity, content of organic matter phosphate, silicate, potassium, calcium, and total nitrogen was increased by application of fresh cattle manure(FCM). Content of Nitrogen in soil layer leached inorganic nitrogen $NO_3$ was higher that that of $NH_4$ and was high in treatment of FCM. Content of $PO_4$ was higher in FCM than other treatments. But content of potassium was in high control. During the growth of rice plant, the amount of water consumption was 477mm. The amount of supplied nitrogen was high in treatment of no nitrogen(NN), 20% reduced application of LCU(LCU-20%), and no fertilizer. In case of phosphate, the supplied amount was more than the consumed amount with the exception of treatment "no phosphate(NP) and no fertilizer(NF)". In case of potassium, the consumed amount was more than the supplied amount in all treatments. The amount of applied nitrogen in the nutrient infiltrated water was high in treatment soil test(ST), C+FCM+Si(Silicate) and the ratio of recovered nitrogen was high in 20% reduced application of LCU. The amount of applied phosphate in the nutrient infiltrated water was high in FCM and that of applied potassium was high in 20% reduced application of LCU. Nitrogen use efficiency of paddy rice was high in 20% reduced application of LCU and use efficiency of phosphate and potassium was high in C+Si(Silicate). Grain yield of rice was high in order of 20% reduced application of LCU>C+Si=C+FCM+Si>C+FCM.

Face Detection Using A Selectively Attentional Hough Transform and Neural Network (선택적 주의집중 Hough 변환과 신경망을 이용한 얼굴 검출)

  • Choi, Il;Seo, Jung-Ik;Chien, Sung-Il
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.4
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    • pp.93-101
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    • 2004
  • A face boundary can be approximated by an ellipse with five-dimensional parameters. This property allows an ellipse detection algorithm to be adapted to detecting faces. However, the construction of a huge five-dimensional parameter space for a Hough transform is quite unpractical. Accordingly, we Propose a selectively attentional Hough transform method for detecting faces from a symmetric contour in an image. The idea is based on the use of a constant aspect ratio for a face, gradient information, and scan-line-based orientation decomposition, thereby allowing a 5-dimensional problem to be decomposed into a two-dimensional one to compute a center with a specific orientation and an one-dimensional one to estimate a short axis. In addition, a two-point selection constraint using geometric and gradient information is also employed to increase the speed and cope with a cluttered background. After detecting candidate face regions using the proposed Hough transform, a multi-layer perceptron verifier is adopted to reject false positives. The proposed method was found to be relatively fast and promising.

A Study on a Classical Construction Paradigm in Modern Fashion (현대 패션에 나타난 고전적 조형 패러다임에 관한 연구)

  • Kim Hye-Young;Lee Shin-Young
    • The Research Journal of the Costume Culture
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    • v.13 no.6 s.59
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    • pp.960-976
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    • 2005
  • Classicism pursued beauty comprised of a perfect form, and beauty was perceived as a state of sufficiency. Accordingly, a completed and permanent beauty was sought after; as a result, a perfect and flawless form became the mainstream, and there was an effort to visualize the eternal proportional perfection. In classicism, forms were perfectly embodied with systematic inevitability and absolute inflexibility, by which an extremely clear aspect appeared. This study analyzes a classical construction paradigm in modern fashion according to the five categories: 'Harmony and order by numerical proportion', 'Clear form', 'Simplification of form and two-dimensional Seh-form', 'Completed contracture structure', and 'Pluralistic unification', and the respective formative characteristics are as follows. First, in terms of the formative aspect of modern fashion,'Harmony and order by numerical proportion' results from thorough observance of extreme and golden section (proportion of 5 :8) which was an aesthetic standard of beautiful body in classicism. Second, 'Clear form' appears in clothes as individual clearness of structural elements expressing each part of body, and shows a well-established form possible to be grasped with equal and clear contour line. Third,'Simplification of form and two-dimensional Seh-form' comes out as form composition, single line, single layer structure, two-dimensional form and arrangement of elements of clothes through the front viewpoint caused by 2D diagramming work while fashion-designing and producing. Also, it is seen that two-dimensional proportion which is composed of sections through various harmonious lines and sides according to the simple two-dimensional compatibility principle is accomplished. Fourth, 'Completed contracture structure' emerges as an expression of stationariness, in other words, fixation of an overall impression. This is a tendency that the overall form is grasped as a fixedly intact shape without a big change of the silhouette of clothes. Fifth, 'Pluralistic unification' means that it respectively emphasizes all the parts composing clothes by making them individually independent at the same time as each element is inclusively shown with the harmony of the overall silhouette of clothes and many other details. This study examined classical formative characteristics through a theoretical research on a formative paradigm revealing the classical style. Also, the significance of classical or rational value of art was illuminated by observing what characteristics a classical formation paradigm shows in modern fashion. As a result, classical characteristics in modern fashion prove that classicism is not a merely past construction style separated from the present but a construction paradigm deeply involved in our reason system.

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Site Characterization using Shear-Wave Velocities Inverted from Rayleigh-Wave Dispersion in Wonju, Korea (레일리파 분산을 역산하여 구한 횡파속도를 이용한 원주시의 부지특성)

  • Kim, Chungho;Ali, Abid;Kim, Ki Young
    • Geophysics and Geophysical Exploration
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    • v.17 no.1
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    • pp.11-20
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    • 2014
  • To reveal shear-wave velocities ($v_s$) and site characterization of Wonju, Korea, Rayleigh waves were recorded at 78 sites of lower altitude using 12 to 24 4.5-Hz vertical geophones for 20 days during the period of February to September 2013. Dispersion curves of the Rayleigh waves obtained by the extended spatial autocorrelation method were inverted using the damped least-squares method to derive $v_s$ models. From these 1-D models, the average $v_s$ to a depth of 30 m ($v_s30$), $v_s$ of weathered rocks, depths to these basement rocks, and average $v_s$ of the overburden layer were derived to be $16.3{\pm}0.7m$, $576{\pm}8m/s$, $290{\pm}7m/s$, and $418{\pm}13m/s$, respectively, in the 95% confidence range. To determine adequate proxies for $v_s30$, we computed correlation coefficients of $v_s30$ with topographic slope (r = 0.46) and elevation (r = 0.43). An empirical linear relationship is presented as a combination of individually estimated $v_s30$ with weighting factors of 0.45, 0.45, and 0.1 for topographic slope, elevation, and mapped lithology, respectively. Due to a weak correlation between $v_s30$ obtained from inversion of dispersion curves and the proxy-based estimation (r = 0.50), however, the relatively large error range should be considered for applications of this relationship.

Histopathological changes in fingerlings of Japanese flounder, Paralichthys olivaceus, with severe scuticociliatosis (스쿠지카섬모충에 중감염된 넙치 (Paralichthys olivaceus) 치어에 대한 병리조직학적 관찰)

  • Lee, Nam-Sil;Park, Jeong-Hee;Han, Kyu-Sik;Huh, Min-Do
    • Journal of fish pathology
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    • v.7 no.2
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    • pp.151-160
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    • 1994
  • In order to elucidate the patterns of tissue damage evoked by the scuticociliatids, eighteen fingerlings of Japanese flounder, Paralichthys olivaceus, heavily infected with an unidentified scuticociliatid were histopathologically examined. Skin layer with the underlying musculature were severely necrotized due to the infestation of the ciliates. However in the early lesions, both dermis and myofibres remained relatively intact compared with other surrounding loose connective tissues. Mild damages were found in more dense tissues. One or more scuticociliatids were recognized in the blood and lymph vessels of the loose connective tissues with or without destructive changes. Many of nerve trunks or ganglia were also parasitized with less marked histological damage in the parenchyma. Dura and its adjacent tissues in the spinal cord were severely necrotized with massive accumulation of the ciliates in subdural space. The parasitic invasion in the central nervous system was usually confined to the cortical region. In the gill, variable degenerative changes were occurred due to the invasion of the ciliates recognized in the blood vessels of branchial arches or primary filaments. From these results, it was strongly suggested that the scuticociliatids are very actively penetrated into the deep tissues mainly through the severe destruction of the loose connective tissue components and that the vascular system could play a role in the rapid distribution of the ciliates to the remote tissues or organs.

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