• Title/Summary/Keyword: artificial chemical

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Evaluation of Water Quality Prediction Models at Intake Station by Data Mining Techniques (데이터마이닝 기법을 적용한 취수원 수질예측모형 평가)

  • Kim, Ju-Hwan;Chae, Soo-Kwon;Kim, Byung-Sik
    • Journal of Environmental Impact Assessment
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    • v.20 no.5
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    • pp.705-716
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    • 2011
  • For the efficient discovery of knowledge and information from the observed systems, data mining techniques can be an useful tool for the prediction of water quality at intake station in rivers. Deterioration of water quality can be caused at intake station in dry season due to insufficient flow. This demands additional outflow from dam since some extent of deterioration can be attenuated by dam reservoir operation to control outflow considering predicted water quality. A seasonal occurrence of high ammonia nitrogen ($NH_3$-N) concentrations has hampered chemical treatment processes of a water plant in Geum river. Monthly flow allocation from upstream dam is important for downstream $NH_3$-N control. In this study, prediction models of water quality based on multiple regression (MR), artificial neural network and data mining methods were developed to understand water quality variation and to support dam operations through providing predicted $NH_3$-N concentrations at intake station. The models were calibrated with eight years of monthly data and verified with another two years of independent data. In those models, the $NH_3$-N concentration for next time step is dependent on dam outflow, river water quality such as alkalinity, temperature, and $NH_3$-N of previous time step. The model performances are compared and evaluated by error analysis and statistical characteristics like correlation and determination coefficients between the observed and the predicted water quality. It is expected that these data mining techniques can present more efficient data-driven tools in modelling stage and it is found that those models can be applied well to predict water quality in stream river systems.

A Study on Development of Automatic Path Tracking Algorithm for LNG Aluminium Plate and Selection of Process Parameters by Using Artificial Intelligence (LNG 알루미늄 판재 가공용 자동 궤적 추적 알고리즘 개발 및 인공지능을 이용한 공정조건 선정에 관한 연구)

  • 문형순;권봉재;정문영;신상룡
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.8
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    • pp.17-25
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    • 1998
  • Aluminum alloys have low density, relatively high strength and yield strength, good plasticity, good machinability, and high corrosion and acid resistance. Therefore, they are suitable for large containers for the food, chemical and other industries. Large containers are often bodies of revolution consisting of shell courses, stiffening rings, heads and other elements joined by annular welds. Larger containers have longer welds and require greater leak-tightness and higher weld mechanical properties. The LNG tank consists of aluminum plates with various sizes, so its construction should by divided by several sections. Moreover, each section has its own sub-section consisted of several aluminum plates. To guarantee the quality of huge LNG tank, therefore, the precise control of plate dimension should by urgently needed in conjunction with the appropriate selection of process parameters such as cutting speed, depth of cut, rotational speed and so on. In this paper, a manufacturing system was developed to implement automatic circular tracking in height direction and automatic circular interpolation in depth of cut direction. Also, the neural network based on the backpropagation algorithm was used to predict the cutting quality and motor load related with the life time of the developed system. It was revealed that the manufacturing system and the neural network could be effectively applied to the bevelling process and to predict the quality of machined area and the motor load.

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Cultural characteristics of fungal species associated with deterioration or foxing of paper and chemical removal (종이변색균류의 배양적 특성 및 화학적 방법에 의한 변색제거)

  • Jo, Seong-Eun;Kim, Yong-Tae;Jeong, So-Yeong;Jo, Byeong-Muk;Lee, Jong-Gyu
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2009.04a
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    • pp.295-303
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    • 2009
  • The annals of Joseon dynasty, especially the volumes of King SeJong(1418-1450 A.D.), were heavily deteriorated by fungi. Investigations on the deteriorating and foxing fungi were carried out. Fungal structures on the beeswax, which were coated on the both side of Han-Ji, were suspected to be involved in the deterioration, and were observed by SEM. Isolation and culturing of these fungi were tried by scrubing swab samples and placing on the artificial media. Culture-independent approaches were used to identify the fungal strains associated with damages of beeswax and foxing of the paper by the analyses based on DNA sequences data from the specific ITS region of rDNA regions. In addition, well-known paper staining fungi(PSF), i.e., Aspergillus terreus var. terreus, Fusarium oxysporum, Chaetomium globosum, Cladosporium cladosporioides, and Alternaria solani, were compared in the mycelial growth and stain on beeswax and papers under different environmental conditions (temperature, light, moisture, etc). Fungal strains isolated from the air samples in the storage room and shelves were identified as Irpex sp., Arthrinium sacchari, Cladosporium tenuissimum, Aspergillus sclerotiorum, Sistotrema brinkmannii, and Hypoxylon bovei var. microsporum The isolated strains were compared in growth and stain patterns on beeswax and papers(Han-Ji, Hwa-Ji, and Yang-Ji) whether these can cause damage or foxing on the annals or not.

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Separation of Taxol from Taxanes by NP-HPLC (정상 액체 크로마토그래피를 이용한 taxane으로부터 taxol의 분리)

  • Chang, Kyung Kon;Row, Kyung Ho;Chung, Sung Taik
    • Applied Chemistry for Engineering
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    • v.8 no.2
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    • pp.286-291
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    • 1997
  • Taxol which is recognized as a powerful anticancer reagent was extracted from yew extract and separated by NP-HPLC (Normal-PhaseHigh Performance Liquid Chromatography). The experiments were performed in the isocratic mode with $5{\mu}l$ to $100{\mu}l$ injection volume and 1ml/min mobile phase flow rate. The major mobile phase was hexane and small amounts of ethanol, methanol, 1-propanol and isopropanol were added to change the retention behavior. Prior to a real sample, the artificial mixture of taxol, cephalomannine and 10-deacetyltaxol was tested. They are hard to be separated because of similar chemical structures. The experimental results showed that the proper composition of mobile phase for separating the three components was found 96% hexane and 4% ethanol(vol.%) or 96% hexane, 2% 1-propanol and 2% methanol(vol.%). Compared to the run time of 80 minutes for the binary system, the mixture was separated within 50 minutes with the less amount of mobile phase for the ternary system. Finally, $1{\mu}g$ of taxol was separated from yew tree extracts under the optimum operating conditions.

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Effects of Road Constructions on Soil Drainage from Paddy Fields

  • Sonn, Yeon-Kyu;Moon, Yong-Hee;Zhang, Yong-Seon;Jung, Kang-Ho;Cho, Hye-Rae;Hyun, Byung-Keun;Shin, Kook-Sik;Han, Kyeong-Hwa
    • Korean Journal of Soil Science and Fertilizer
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    • v.48 no.3
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    • pp.189-193
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    • 2015
  • Bad drainage problems from paddy fields adjacent to roads are caused by higher constructed roads which change topography of paddy fields to concave topography and artificial pan to prevent road erosion when road constructions are occurred. This study investigated effects of topography changes on soils by road constructions. Soil samples were investigated by physico-chemical analyses and micromorphology analyses from representative soil profile of Sachon series and soil samples. The characteristics of Sachon series that were adjacent to roads were fewer redoximorphic features (RMF) and increase in grey layers than the original Sachon series. The characteristics of Yecheon Series were shown from Jeollanamdo - Suncheon > Chungchungnamdo - Cheonan > Gangwondo - Wonju. Mosaic speckles were shown from micromorphological analyses because of repeat of shrink and expansion by wetting and drying. The location of graying in soil clods were found from coarse stone blocks to fine stone blocks and color changes of composed particles were also found.

The development of herbicide-resistant maize: stable Agrobacterium-mediated transformation of maize using explants of type II embryogenic calli

  • Kim, Hyun A.;Utomo, Setyo Dwi;Kwon, Suk Yoon;Min, Sung Ran;Kim, Jin Seog;Yoo, Han Sang;Choi, Pil Son
    • Plant Biotechnology Reports
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    • v.3 no.4
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    • pp.277-283
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    • 2009
  • One of the limitations to conducting maize Agrobacterium-mediated transformation using explants of immature zygotic embryos routinely is the availability of the explants. To produce immature embryos routinely and continuously requires a well-equipped greenhouse and laborious artificial pollination. To overcome this limitation, an Agrobacterium-mediated transformation system using explants of type II embryogenic calli was developed. Once the type II embryogenic calli are produced, they can be subcultured and/or proliferated conveniently. The objectives of this study were to demonstrate a stable Agrobacterium-mediated transformation of maize using explants of type II embryonic calli and to evaluate the efficiency of the protocol in order to develop herbicide-resistant maize. The type II embryogenic calli were inoculated with Agrobacterium tumefaciens strain C58C1 carrying binary vector pTF102, and then were subsequently cultured on the following media: co-cultivation medium for 1 day, delay medium for 7 days, selection medium for $4{\times}14$ days, regeneration medium, and finally on germination medium. The T-DNA of the vector carried two cassettes (Ubi promoter-EPSPs ORF-nos and 35S promoter-bar ORF-nos). The EPSPs conferred resistance to glyphosate and bar conferred resistance to phosphinothricin. The confirmation of stable transformation and the efficiency of transformation was based on the resistance to phosphinothricin indicated by the growth of putative transgenic calli on selection medium amended with $4mg\;1^{-1}$ phosphinothricin, northern blot analysis of bar gene, and leaf painting assay for detection of bar gene-based herbicide resistance. Northern blot analysis and leaf painting assay confirmed the expression of bar transgenes in the $R_1$ generation. The average transformation efficiency was 0.60%. Based on northern blot analysis and leaf painting assay, line 31 was selected as an elite line of maize resistant to herbicide.

Study on the Separation of $^{55}Fe$, $^{90}FSr$$^{94}Nb$ in Radioactive Wastes (방사성 폐기물 내 $^{55}Fe$, $^{90}FSr$$^{94}Nb$의 분리 연구)

  • 이창헌;정기철;임석남;김원호;지광용
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2003.11a
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    • pp.54-59
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    • 2003
  • Several radionuclides are considered as an object of the assesment to develop a scaling factor and a periodical verification method which are needed for the evaluation of radionuclide inventory of various radioactive wastes from nuclear power plants in Korea. A selective separation of $^{55}Fe$, $^{90}FSr$$^{94}Nb$ which should be recovered individually for the radiochemical analysis was described in detail. Sorption and desorption behaviours of ion exchange and extraction chromatographic resins for Fe, Sr, Nb and co-existing metal ions were Investigated using an artificial waste solution simulated of chemical composition of real radioactive wastes. Separation conditions available for the sequential recovery of these metal ions from a single sample were optimized to minimize a discharge of radioactive wastes produced through the analytical process and a radiation exposure to analysts. Their recovery yields were measured with reliability.

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Soil Characteristics and Management Proposal of the Monument Beobsoo Marsh, Korea (천연기념물 법수늪의 토양특성 및 관리방안)

  • Kim, Do-Gyun;Kim, Yong-Shik
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.14 no.3
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    • pp.15-32
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    • 2011
  • This study was carried out to investigate the soil characteristics and propose the management for the Monument Beobsoo Marsh, Korea. The soil properties of O.M, $Ca^{2+}$, $Na^+$ and CEC were higher and the soil properties of pH_{1:5}$ and $P_2O_5$ were lower the studied sites than other marsh sites in Korea. Although the Heavy metals such as Pb, Hg, Cd, Cu, Zn, Cr and As were lower compare to the safety standard of soil pollution in Korea, the overall conservation management plan based on long-term monitoring should be considered just because it varied by the point and non-point source pollution within the studied marsh. The source of water pollution varied due to non-point polluting origins such as sewage inlet, degraded terrain for agriculture, fishing sites, sites of removed water grasses, pesticides, chemical fertilizers, as well as fallen leaves. The creation of an artificial marsh is recommended due to the soil environment of the studied sites may be changed owing to the accumulated contaminants from the sources of both of point or non-point contaminants. The establishment of the zones of core, buffer and transition which is basic management structure of the UNESCO MaB could be applied to manage the studied site. Simultaneously the promotion of voluntary participation and education of the local residents are needed.

Adhesive characteristics of water-paint and silane adhesive mixture (수성페인트-실란접착제 혼합물의 접착특성)

  • HAN, Hyun Kak
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.8
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    • pp.5721-5727
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    • 2015
  • Paint must be resistant to the wear and tear of the atmosphere and should maintain its color and finish for a long time. The solvents of paints were organic solvent and water, common artificial source of VOCs(Volatile organic Solvent) include organic solvent. Using of organic solvent paint was decreased in the interior parts of automotive, exterior parts were still used organic solvent paint. Adhesive strength of water-paint was poor to compare with organic solvent paint and peeled off from the base materials, it was big quality problem. In this study, adhesive characteristics of water-paint and silane mixture was investigated. To improve adhesive strength of water-paint, it was necessary to mixing of adhesive material. Adhesive strength was measured using UTM(Universal Test Instrument) by ASTM D1002 and Peeling off condition was by ASTM D3359. Optimal mixing condition of water-paint and silane adhesive were $25^{\circ}C$, 500rpm, 20min., concentration of silane adhesive was 5 wt%.

Temperature-Range-Dependent Optimization of Noninvasive MR Thermometry Methods (온도범위에 따른 비침습적 자기공명 온도측정방법의 최적화)

  • Kim, Jong-Min;Kumar, Suchit;Jo, Young-Seung;Park, Joshua Haekyun;Kim, Jeong-Hee;Lee, Chulhyun;Oh, Chang-Hyun
    • Journal of Biomedical Engineering Research
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    • v.36 no.6
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    • pp.241-250
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    • 2015
  • Noninvasive temperature monitoring is feasible with Magnetic Resonance Imaging (MRI) based on temperature sensitive MR parameters such as $T_1$ and $T_2$ relaxation times, Proton Resonance Frequency shift (PRFs), diffusion, exchange process, magnetization transfer contrast, chemical exchange saturation transfer, etc. While the temperature monitoring is very useful to guide the thermal treatment such as RF hyperthermia or thermal ablation, the optimization of the MR thermometry method is essential because the range of temperature measurement depends on the choice of the measurement methods. Useful temperature range depends on the purpose of treatment methods, for example, $42^{\circ}C$ to $45^{\circ}C$ for RF hyperthermia and over $50^{\circ}C$ for thermal ablation. In this paper, MR thermometry methods using $T_1$ and $T_2$ relaxation times and PRFs-based MR thermometry are tried on a 3.0 T MRI system and their results are reported and compared. In addition, the scanning protocol and temperature calculation algorithms from $T_1$ and $T_2$ relaxation times and PRFs are optimized for the different temperature ranges for the purpose of RF hyperthermia and/or thermal ablation.