• Title/Summary/Keyword: harmful

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Ion Exchange Processes: A Potential Approach for the Removal of Natural Organic Matter from Water

  • Khan, Mohd Danish;Ahn, Ji Whan
    • Journal of Energy Engineering
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    • v.27 no.2
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    • pp.70-80
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    • 2018
  • Natural organic matter (NOM) is among the most common pollutant in underground and surface waters. It comprises of humic substances which contains anionic macromolecules such as aliphatic and aromatic compounds of a wide range of molecular weights along with carboxylic, phenolic functional groups. Although the concentration of NOM in potable water usually lies in the range of 1-10 ppm. Conventional treatment technologies are facing challenge in removing NOM effectively. The main issues are concentrated to low efficiency, membrane fouling, and harmful by-product formation. Ion-exchangers can be considered as an efficient and economic pretreatment technology for the removal of NOM. It not only consumes less time for pretreatment but also resist formation of trihalomethanes (THMs), an unwanted harmful by-product. This article provides a comprehensive review of ion exchange processes for the removal of NOM.

Red Tide Blooms Prediction using Fuzzy Reasoning (퍼지 추론을 이용한 적조 발생 예측)

  • Park, Sun;Lee, Seong-Ro
    • The KIPS Transactions:PartB
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    • v.18B no.5
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    • pp.291-294
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    • 2011
  • Red tide is a temporary natural phenomenon to change sea color by harmful algal blooms, which finfish and shellfish die en masse. There have been many studies on red tide due to increasing of harmful algae damage of fisheries in Korea. Particularly, red tide damage can be minimized by means of prediction of red tide blooms. However, the most of red tide research in Korea has been focused only classification of red tide which it is not enough for predicting red tide blooms. In this paper, we proposed the red tide blooms prediction method using fuzzy reasoning.

The Report on the Taxonomic Characters, Ecological Risk and Weed Risk Assessment of Putative Invasive Alien Plants which are Designated in Law by the Ministry of Environment in Korea as Environmentally Harmful Species (II)

  • Hyun, JongYoung;Yoon, ChangYoung;Kim, Joo-Hwan
    • Korean Journal of Plant Resources
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    • v.33 no.3
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    • pp.200-219
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    • 2020
  • We performed taxonomic reviews and habitat circumstances survey for 41 un-introduced environmentally harmful plants (as designated by the Ministry of Environment, Korea in 2016). For this purpose, we investigated plant specimens from several herbaria and performed a field survey in the southeastern region of the United States. Base on the result, we presented the most comprehensive results of weed risk evaluation and taxonomic description up to now as well as classification keys for 11 species to apply the regulation management of putative invasive alien species - Centaurea maculosa Lam., Centaurea diffusa Lam., Mikania micrantha Kunth. (Asteraceae), Cenchrus echinatus L., Neyraudia reynaudiana (Kunth) Keng ex Hitchcock, Brachiaria mutica (Forsskål) Stapf, Vulpia bromoides (L.) Gray, Lolium persicum Boissier & Hohennacker, Setaria palmifolia (J. Konig) Stapf (Poaceae), Prosopis glandulosa Torr. (Fabaceae), Fallopia baldschuanica (Regel) Hobub. (Polygonaceae).

Development of Adult Authentication System using Numeral Recognition (숫자인식을 이용한 성인인증기 개발)

  • 김갑순;박중조
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.12
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    • pp.100-108
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    • 2002
  • This paper describes the development of adult authentication system using numerical recognition. Nowadays, the automats are very popular and they are dealing in many item suck as coffee, soft drinks, alcoholic drinks and cigarettes, etc. Among these items, some are harmful to the minor, and so the sale of these to the minor must be prohibited. In relation to this, adult authentication system is required to be equipped to the automat which deals in items harmful to minor. According to these demands, we develop the adult authentication system. This system capture the image of a residence certificate card by the identification card-reader, and recognize its numbers and identify it as adult or minor by main computer, where numeral recognition is accomplished by using image processing methods and neural network recognizer. The characteristic test of the system is carried out, and its result reveals that the system has the error of less than 1%. Thus, It is thought that the system can be used for identifying adult in the automats.

생채 유해균주 제어를 위한 천연산물의 탐색

  • Kim, Jong-Deok;Kim, Min-Yong;Sin, Tae-Seon;Kim, Dae-Hyeon;Gong, Jae-Yeol
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.737-740
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    • 2000
  • Two groups of bacteria, harmful and useful bacteria, coexist in our body. Harmful bacteria and free radicals which cause many diseases and agings could be controlled by not synthetic materials but natural products. 50 kinds of natural products were searched for this purpose, some of them expressed bacterial controlling ability. Clostridium difficle was controlled by Paeonia Japonica and Lycii Fructus, etc., Clostridium perfringens was inhibited by Scutellaria Baicalensis and Astragali Radix, etc., and same way, Listeria monocytogenes; Paeonia Japonica and Scutellaria Baicalensis, E. coli; Scutellaria Baicalensis and Schizandrae Fructus, Staphylococcus aureus; Paeonla Japonica and Scutellaria Baicalensis, Streptococcus mutans; Coptis Rhizoma, respectively. These natural products will play an important role in bio-Industry.

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Strength Characteristic according to the 80℃ Water Curing Time Variation of the Ternary System Inorganic Binder (3성분계 무기결합재의 80℃ 수중양생 시간변화에 따른 강도특성)

  • Lee, Jin-Woo;Lee, Sang-Soo;Song, Ha-Young
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.100-101
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    • 2014
  • The global warming because of the CO2 emission and solution about this emerge as the international enviroment problem. Particularly, it is the absolutely it is needed for reducing the CO2 in the cement industry and harmful material actual condition. And the construction of home and abroad and material manufacturers tries for the technology development for the carbon dioxide and harmful material reduction which the portland cement in manufacture is usually emitted along with the increase of concerns about the environment-friendly concrete and panel. Therefore, in this research, the compressive strength of the inorganic binder and flexural strength tries to be measured in order to draw the inappropriate high temperature cure time of the ternary system inorganic binder using the blast furnace slag, red mud, silica fumewhich is the industrial byproduct with the cement substitute material, and etc.

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A Study on the Physical Properties of MgO Board for Wall System (경량 벽체용 MgO 보드의 물리적 특성에 관한 실험적 연구)

  • Kim, Soon-Ho;Kim, Hong-Yong
    • KIEAE Journal
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    • v.7 no.4
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    • pp.135-140
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    • 2007
  • In this study we settled the trouble of the MgO board of existence by this research. We changed the wooden one of the main ingredient of a board to a perlite and a mineral particle in the aluminum hydroxide group and proceeded with a study to physical character and fire resistance efficiency improvement. The result yellowing phenomenon could be improved and it was possible to reduce size decrease of pin hole and the frequency of occurrence. We found out that the in case of absorbed amount added 5~8% corresponding to the weight decreases the acrylic group emulsion suddenly. So this product is improved with the bending strength and water-resistance. After behavior stop time measurement of a mouse for experiments was measured at the time of a gas harmful effect test, an improved MgO board appeared more highly for an average of 138 seconds compared with a board of existence.

An Effect of Harmful Materials During Welding Work (용접 작업 중 발생하는 유해물질의 영향)

  • Lee, Kyung-Man;Lee, Chul-Ku
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.17 no.1
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    • pp.43-49
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    • 2008
  • This study is about an influence of harmful factors of welding fumes such as Fe, Mn, Cu, Zn to workers who inhales them in welding sites. The influence can be measured with the density of heavy metals in blood after welding. The main factors of the measurement are TWA, a density of welding fume, and a level of heavy metals. The results indicate that there is a positive effect of moving fans as a way of improving the condition in welding workplaces. While welding was done, TWA exceeded the level of Fe 40% and Zn 10% and the level of heavy metals in blood was below the standard for the workers who were under the experiment. Also when the wind was applied on the front side by a fan, the welding fume significantly reduced. It can be concluded that wearing protection gears with safety devices is one of important factors.

The effects of Ultrasound on the Platelet of Rats (초음파가 생쥐의 혈소판에 미치는 영향)

  • Cho, Kwang-Ho;Park, Sang-Ock;Park, Rae-Joon
    • The Journal of Korean Physical Therapy
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    • v.13 no.1
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    • pp.139-149
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    • 2001
  • We found out that there exists threshold dose for the decreased platelet count when we apply change of the platelet count to the defense of the ultrasound experiment. Those diminution is definite effects from the defense of the ultrasound. The number of the platelet count is decreased when we are exposed to ultrasound simultaneously. This should not be occurred. It is easy to use the number of the platelet count in the measurement of the biological dosage and intensity in high dosage relatively due to definite quantative relationship. The biological index to understand synergic effects. which are present when two harmful environmental factors are operating at the same time is functionally assending and antagonistic. There are scattered many factors as physical, Chemical, or physiochemically elements which are harmful to human body in the environment in consideration of ultrasound and the other factors. This experiment is demonstrating that we can use the change of the platelet as an index representing synergic effects of ultrasound.

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Potential Association between Insulin-like Growth Factor-1 Receptor Activity and Surf Clam Spisula sachalinensis Larvae Survival

  • Choi, Youn Hee;Nam, Taek Jeong
    • Fisheries and Aquatic Sciences
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    • v.18 no.4
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    • pp.417-420
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    • 2015
  • We investigated the relationship between viability and IGF-1 receptor (IGF-1R) activity in D-shaped and umbo larvae of the surf clam Spisula sachalinensis after treatment with vitrification solution (VS) or freezing. In a toxicity assay, VS1, containing 5 M dimethyl sulfoxide (DMSO), was very harmful to D-shaped and umbo larvae. However, VS2, containing 5 M ethylene glycol (EG), was not harmful to either larval stage. Although VS2 had a promising toxicity test outcome, none of the larvae survived vitrification. After immersion into VSs and freezing, IGF-1R ${\beta}$-subunits were detected in all larvae; however, tyrosine phosphorylation of intracellular ${\beta}$-subunits was detected only in the control and live groups. These results suggest that activation of IGF-1R may influence surf clam larvae viability.