• Title/Summary/Keyword: toxic reduction

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The disposal process for scrapped FRP fishing vessels (감척으로 인한 FRP 어선의 처리방안)

  • Song, Jung-Hun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.44 no.1
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    • pp.75-80
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    • 2008
  • A scrapped fiber-reinforced plastic(FRP) fishing vessel causes many environmental problems, because technology development for recycling FRP vessel has not been adequately addressed. FRP is a main material for constructing a small coastal fishing vessel that is an object of reduction policy. Therefore, the FRP wastes derived a scrapped fishing vessel are increasing. In this study, I investigated an effective disposal process for FRP through the analysis of the actual conditions of scrapped FRP fishing vessel. The treatment processes of scrapped FRP fishing vessel are carried out with oil-removing, dismantling, intermediated processing(crushing), and then reclaiming follows burning in the final processing in Korea. However, in Japan, several recycling methods have been developed, for example, the incineration including thermal recovery, the use of cement-reclamation, and the use of asphalt concrete aggregate, because the method of reclaiming after incinerating which is generally used in Korea produces a toxic by-product such as dioxin.

A study on the fire risk analysis on the railway tunnel and subway area (철도터널 및 지하구간에서의 화재사고 위험성 분석 연구)

  • Wang Jong Bae;Hong Seon Ho;Kim Sang Ahm;Park Ok Jeong
    • Proceedings of the KSR Conference
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    • 2003.10b
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    • pp.271-276
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    • 2003
  • In this paper, various hazard factors are reviewed on the train fire accident in railway tunnel and subway. In case studies of systematic risk evaluation on the tunnel fire accident, we have learned the critical fire safety points for accident prevention and damage reduction such as fire-endurance of infrastructure, mortality of heat & toxic smoke, emergency situation control and management of escape requirements etc.. These hazard analysis study will contribute for improving the railway fire-safety and establishing the long-tenn safety management plan.

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The Effect of Nonionic Surfactants on the Solubility and Biodegradation of PAHs in Soil Slurry (PAHs의 용해도와 생분해에 미치는 비이온계 계면활성제의 영향)

  • 박종섭;김인수
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 1998.11a
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    • pp.174-177
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    • 1998
  • The effects of surfactants affecting polycyclic Aromatic Hydrocarbon(PAHs) solubility and biodegradation in soil slurry were investigated. The critical micelle concentration(CMC) values of surfactants used in this study were 12.7mg/L(Brij 30), 13.4mg/L(Tween 80), 13.6mg/t(Triton X-100). The solubility of PAH increased as the Hydrophile-Lipophile Balance(HLB) value of surfactant decrease. At surfactant biodegradation and toxicity experiement using respirometer, Brij 30 did not show any toxic effect and substrate inhibition upon the level of 1.5g/L. Also, biodegradation of Brij 30 gave no reduction on the phenanthrene biodegradation rate. When the desorption rate of phenanthrene between sand and clay is compared, lower percentage of phenanthrene was desorbed at clay because of the larger surface aera and higher organic content of clay. At the biodegradation experiments of phenanthrene in soil slurry phase, more than 90% of initial phenanthrene adsorbed onto both sand and clay were biodegraded by phenanthrene- acclimated cultures.

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Synthesis of the $CaGa_2S_4:Eu^{2+}$ phosphors and Application in White LEDs

  • Kim, Jae-Myung;Kim, Kyung-Nam;Park, Joung-Kyu;Kim, Chang-Hae;Jang, Ho-Gyeom
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1623-1626
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    • 2005
  • The thiogallate phosphors which are well known for a long time as phosphor materials for CRT or EL device were reported. Those have high luminescent properties at long-wavelength region. Among those phosphors, the samples with divalent europium doped CaGa2S4 were prepared by a simple process under the reduction atmosphere $(5%\;H_2/\;95%\;N_2)$ without toxic gas such as H2S or CS2. The prepared phosphor shows a higher luminescent efficiency (about 120%) than that of $YAG:Ce^{3+}$ phosphor. Consequently, this phosphor is possible to be applicable to white LED lamp because of the high luminescent efficiency.

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Development and Evaluation of Human Reliability Analysis Model for the Reduction of Human Errors (인적오류 저감을 위한 인간 신뢰도 분석 체계 및 평가에 관한 연구)

  • Jung, Kyung-Hee;Byun, Seong-Nam;Cho, Jai-Rip
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.2048-2051
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    • 2010
  • Almost all companies have paid much attention to the safety management ranging from maintenance to operation even at the stage of designing in order to prevent accidents, but fatal accidents continue to increase throughout the world. In particular, it is essential to systematically prevent such fatal accidents as fire, explosion or leakage of toxic gas at factories in order to not only protect the workers and neighbors but also prevent economic losses and environmental pollution. In addition, HRA may be used to detect the human errors which may cause accidents or trace back to any mistake on the part of workers. Usually, HRA technique is used in association with other risk assessment techniques. Moreover, it can serve to enumerate the human errors which may occur during operation or down-time or correct the existing system to reduce the mistakes. This work focuses on the coincidence of human error and mechanical failure for management of human error, and on some important performance shaping factors to propose a method for improving safety effectively of the process industries.

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Implementation of unsupervised clustering methods for measurement gases using artificial olfactory sensing system (인공 후각 센싱 시스템을 이용한 측정 가스의 Unsupervised clustering 방법의 구현)

  • 최지혁;함유경;최찬석;김정도;변형기
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.405-405
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    • 2000
  • We designed the artificial olfactory sensing system (Electronic Nose) using MOS type sensor array fur recognizing and analyzing odour. The response of individual sensors of sensor array, each processing a slightly different response towards the sample volatiles, can provide enough information to discriminate between sample odours. In this paper, we applied clustering algorithm for dimension reduction, such as linear projection mapping (PCA method), nonlinear mapping (Sammon mapping method) and the combination of PCA and Sammon mapping having a better discriminating ability. The odours used are VOC (Volatile chemical compound) and Toxic gases.

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Alternative Methods for Testing Botulinum Toxin: Current Status and Future Perspectives

  • Nepal, Mahesh Raj;Jeong, Tae Cheon
    • Biomolecules & Therapeutics
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    • v.28 no.4
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    • pp.302-310
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    • 2020
  • Botulinum toxins are neurotoxic modular proteins composed of a heavy chain and a light chain connected by a disulfide bond and are produced by Clostridium botulinum. Although lethally toxic, botulinum toxin in low doses is clinically effective in numerous medical conditions, including muscle spasticity, strabismus, hyperactive urinary bladder, excessive sweating, and migraine. Globally, several companies are now producing products containing botulinum toxin for medical and cosmetic purposes, including the reduction of facial wrinkles. To test the efficacy and toxicity of botulinum toxin, animal tests have been solely and widely used, resulting in the inevitable sacrifice of hundreds of animals. Hence, alternative methods are urgently required to replace animals in botulinum toxin testing. Here, the various alternative methods developed to test the toxicity and efficacy of botulinum toxins have been briefly reviewed and future perspectives have been detailed.

Operation Characteristics of an UASB at High Organic Loading Condition for Thermal Elutriated Acids of Piggery Wastewater Treatment (가축분뇨 고온 세정산발효액 처리를 위한 고부하 조건에서의 UASB 운전특성)

  • Kwon, Koo-Ho;Jung, Yong Jun;Min, Kyung-Sok
    • Journal of Korean Society on Water Environment
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    • v.28 no.6
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    • pp.781-785
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    • 2012
  • This study was carried out to treat the thermal elutriated acids of piggery wastewater using UASB process. The UASB reactor was operated at an organic loading rate (OLR) of $7.4\;kgCOD/m^3-day$ (6.5 ~ 9.0). During the start-up period, the low COD removal efficiency (20%) was caused by shock loading and instability in the reactor. It was mainly due to the high concentration amounts of ammonia nitrogen, which caused inhibitory and toxic effects to toward the anaerobic bacteria. In steady state, the UASB reactor showed a SCOD removal efficiency of 71% and a VS removal efficiency of 39%. The gas production and methane content were 1.3 L/day $(0.21\;m^3\;CH^4/kg$ COD removed) and 77%, respectively.

Numerical Simulations on Reduction of Toxic Gas Propagation at High-Rise Apartment Building Fires (계단형 공동주택 화재시 독성가스 전파 저감에 관한 수치해석적 연구)

  • Lee, Seong-Chul;Hong, Yi-Pyo;Park, Young-Rok
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.04a
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    • pp.255-258
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    • 2008
  • 본 연구에서는 이전의 연구를 통해 계단형 공동주택 화재 시 재실자 피난특성 및 연기거동에 관한 연구를 실물실험을 통해 수행한 바 있으나 이때 야기된 문제점들을 적절한 방재설비를 도입함으로써 일부 해소하고자 하였다. 따라서 본 연구에서는 이전의 연구와 동일한 대상 건물과 조건에서 수치해석을 수행하며 특히 계단실에 방재설비(배연팬 등) 설치 유 무에 따른 독성가스의 전파 특성 및 최상층까지의 도달시간등을 비교 검토하였다. 계단형 공동주택에서 층간에 배연팬이 설치되어 작동되는 경우가 배연팬이 없는 경우보다 약 45%의 CO 방출량을 줄일 수 있을 것으로 판단되지만 1층 출입구를 통해 유입되는 공기량은 배연팬이 없는 경우가 배연팬이 설치되어 작동되는 경우보다 약 23% 크기 때문에 이로 인해 제연풍속의 증가를 가져올 수도 있을 것이다.

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Concentrations of PCBs (Polychlorinated Biphenyls) in coastal sediments of Korea (국내 연안 퇴적물내 PCBs(Polychlorinated Biphenyls) 오염도 현황)

  • Kim, Gi-Whan;Lee, Yoon
    • Journal of environmental and Sanitary engineering
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    • v.11 no.3
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    • pp.9-12
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    • 1996
  • Polychlorinated biphenyl (PCBs) is one of major toxic pollutants in marine environments, This artificial chlorinated compound has been found in freshwater, seawater, soil, sediments and organismes living in various environments. Because of its toxicity and degradability, its uses in industrial processes have been banned after 1984 in Korea. Coastal area is an important environment for agriculture, industry, transportation, reduction of pollution loads through biogeochemical processes, cycling of nutrients and recreation. Input of pollutants from land and freshwater has been occurring through runoff, rivers and estuaries. Concentrations of PCBs were determined with GC-ECD. Concentrations of PCBs were in the range of 1.0 - 19.2 ng/g-dry weight of sediment(g-d.w.) at Ulsan, 4.5 -8,2 ng/g-d.w. at Onsan, 2.7 - 33.5 ng/g-d.w. at Masan and 4.0 - 60.7 ng/g-d.w. in Kwangyang, In Inchon area, PCBs were not detected in sediments. In sediments of Nakdong estuary, the distribution of PCBs' concentrations was 0.19 - 303 ng/g-d.w.

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