• 제목/요약/키워드: successive elimination

검색결과 39건 처리시간 0.027초

쌀의 취반 중 Phenthoate 농약 잔류분의 제거 (Elimination of Phenthoate Residues in the Washing and Cooking of Polished Rice)

  • 김남형;이미경;이서래
    • 한국식품과학회지
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    • 제28권3호
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    • pp.490-496
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    • 1996
  • 인위적으로 phenthoate 농약성분을 부착시킨 쌀의 취반(炊飯), 즉 수세 및 가열조리시 농약잔류분의 제거율을 실험한 결과는 다음과 같다. 가정에서의 세척방법에 준하여 3회 반복 수세한 쌀에서 phenthoate는 49%가 잔존하였으므로 수세에 의해 51%가 제거되었다. 수세과정에서는 첫 번째 세척액(뜨물)에서 37.3% (여과액 7.8, 잔사 29.5%), 두 번째 세척액에서 14.3% (여과액 6.2%, 잔사 8.1), 세 번째 세척액에서 8.9% (여과액 5.8. 잔사 3.1%)가 제거되었다. 세척액 중 phenthoate 잔류분은 뜨물 여과액보다 뜨물 잔사에서 더 많이 발견되었다. 전기밥솥에서 가열조리한 쌀밥에서 phenthoate 잔존율은 41%이었으므로 수세 및 가열조리에 의해 오염된 phenthoate의 595가 제거되었다. Phenthoate 성분은 열에 안정해 취반시에도 분리되지 않는 것으로 생각된다. 결론적으로 쌀 중에 잔류하는 phenthoate 성분은 취반과정시 주로 수세과정에 의하여 제거되므로 가열조리전 수세과정을 반드시 3회 이상 거치는 것이 바람직하다. 본 연구결과는 쌀 중 phenthoate의 잔류 허용기준 설정시 감소계수(0.4)로 활용될 수 있을 것이다.

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변압기 오일 내 PCBs의 화학적 탈염소공정: 실용적인 접근 (Chemical Dechlorination Process of PCBs in Industrial Transformer Oil: Approach to Practical Use)

  • 유건상;변상혁;최종하
    • 한국환경과학회지
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    • 제18권9호
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    • pp.953-959
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    • 2009
  • A practical and efficient disposal method for chemical dechlorination of PCBs (polychlorinated biphenyls) in transformer oil was evaluated. The transformer oil containing PCBs was treated by the PEG 600 (polyethylene glycol 600) and potassium hydroxide (KOH) along with different reaction temperatures(25, 50, 100 and $150^{\circ}C$) and times(30, 60, 240 and 480 min). The best disposal efficiency of PCBs in transformer oil was attained under the experimental conditions of PEG 600 (2.5 w/w%)/KOH (2.5 w/w%)/$150^{\circ}C$/4 hrs, showing completely removal of all PCBs containing 3-9 chlorines on two rings of biphenyl. In studying the reaction of PEG/KOH with PCBs, it confirmed that the process led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines.

플라즈마 스프레이 (Ca, Co)-Doped LaCrO3 코팅층의 치밀화 및 전기전도도 (Densification and Electrical Conductivity of Plasma-Sprayed (Ca, Co)-Doped LaCrO3 Coating)

  • 박희진;백경호
    • 한국재료학회지
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    • 제27권3호
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    • pp.155-160
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    • 2017
  • Doped-$LaCrO_3$ perovskites, because of their good electrical conductivity and thermal stability in oxidizing and/or reducing environments, are used in high temperature solid oxide fuel cells as a gas-tight and electrically conductive interconnection layer. In this study, perovskite $(La_{0.8}Ca_{0.2})(Cr_{0.9}Co_{0.1})O_3$ (LCCC) coatings manufactured by atmospheric plasma spraying followed by heat treatment at $1200^{\circ}C$ have been investigated in terms of microstructural defects, gas tightness and electrical conductivity. The plasma-sprayed LCCC coating formed an inhomogeneous layered structure after the successive deposition of fully-melted liquid droplets and/or partially-melted droplets. Micro-sized defects including unfilled pores, intersplat pores and micro-cracks in the plasma-sprayed LCCC coating were connected together and allowed substantial amounts gas to pass through the coating. Subsequent heat treatment at $1200^{\circ}C$ formed a homogeneous granule microstructure with a small number of isolated pores, providing a substantial improvement in the gas-tightness of the LCCC coating. The electrical conductivity of the LCCC coating was consequently enhanced due to the complete elimination of inter-splat pores and micro-cracks, and reached 53 S/cm at $900^{\circ}C$.

APPLICATION OF BENFOR'S EQUATIONS TO THE PROBLEM OF "SEEING THROUGH LAYERS"

  • Krivoshiev, Georgi -P.;Chalucova, Raina-P.;Dahm, Donald-J.
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1132-1132
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    • 2001
  • This work is a further development of the method created by G. Krivoshiev in 1996 for elimination of peel interference and prediction of fruit flesh optical density. In this investigation, as it was earlier, the objects are observed as being structured by three successive layer “AlongrightarrowOlongrightarrowB” denoting “peel-flesh-peel”. In the first version of the method the transmittances of the surface layers A and B were measured according to Kubelka-Munk theory by means of their diffuse reflectance. At that the overall transmittance T was approximated in the form of a multiplication approximation being valid for plane-parallel layers of a non-scattering material. In this work this approximation was done away with applying the theory of discontinuum, respectively Benfor's equations. As a result two mathematical models were created for non-destructive prediction of fruit flesh optical density. These models are different from the ones based solely on Kubelka-Munk theory, the destruction being marked by the terms 1n (1 - $R_{A}R_{0}$) and 1n (1 - $R_{A}R_{B}$), where: $R_{A}$ and $R_{B}$ are reflectance values for the surface layers A and B; $R_{0}$ is the average reflectance of the internal layer that could be obtained empirically by means of a preliminary measurement of sufficiently large number of physically peeled fruits of a given species and variety.

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중풍치료(中風治療)에서 충류약(蟲類藥)의 활용(活用)에 관(關)한 연구(硏究) (A Literature Study of the Effect of Hirudo, Lumbricus, Scolopendra, and Scorpio on Apoplexy)

  • 홍시내;신현철;정지천
    • 대한한방내과학회지
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    • 제17권1호
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    • pp.107-122
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    • 1996
  • Apoplexy is a disease of a morbid condition manifested as sudden syncope, unconciousness, distortion of face, hemiplegia and dysphasia, usually seen in the middle-aged. The symptoms and signs before sudden onset are headache, dizziness, numbness of extremities, palpitation, etc. This study was performed to investige causes of disease, therapies and prescriptions by insect medicine through the successive medical literatures, recent chinese medical literatures and chinese medical journals. The results are as follows; 1. The treatment of apoplexy is divided into stage of attack and sequela. In stage of attack, the principal therapies of apoplexy are calming the liver, suppressed Yang, dissipate phlegm and elimination weatness. In sequela, the principal therapies of apoplexy are invigorating Qi, promote blood circulation and dredge collateral. 2. Insects medicine have more strong effect than herbal medicine, because apoplexy is a kind of critically desease. 3. Insects medicine is effective in a convalscent stage and sequela of apoplexy. The proper dosage for stage of attack is a small dose of insects medicine(about 2-4g), increse gradually. In convalscent stage, about 4g, in sequela, patients need a large dose of insects medicine(about 8g). 4. Hirudo used to remove stagnated blood and to disperse swelling for the treatment of severe cases of blood stasis, such as cerebral infarction, sequela of cerebrovascular accident, contused wounds. Lumbricus used to for the treatment of convulsions due to high fever, and for hemiplegia and hypertension. Scolopendra used to subdue the endogenous wind for the treatment of various kinds of tics, convulsions and tetanus, and it's character is strong because it will be effective Sthenia-Syndrome of apoplexy. Scorpio used to subdue the endogenous wind for the treatment of various kind of tics, convulsions, tetanus and sequela of cerebrovascular accident.

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Destruction and Removal of PCBs in Waste Transformer Oil by a Chemical Dechlorination Process

  • Ryoo, Keon-Sang;Byun, Sang-Hyuk;Choi, Jong-Ha;Hong, Yong-Pyo;Ryu, Young-Tae;Song, Jae-Seol;Lee, Dong-Suk;Lee, Hwa-Sung
    • Bulletin of the Korean Chemical Society
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    • 제28권4호
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    • pp.520-528
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    • 2007
  • A practical and efficient disposal of PCBs (polychlorinated biphenyls) in waste transformer oil by a chemical dechlorination process has been reported. The transformer oil containing commercial PCB mixtures (Aroclor 1242, 1254 and 1260) was treated by the required amounts of PEG 600 (polyethylene glycol 600), potassium hydroxide (KOH) and aluminum (Al), along with different reaction temperatures and times. The reaction of PEG with PCBs under basic condition produces arylpolyglycols, the products of nucleophilic aromatic substitution. The relative efficiencies of PCB treatment process were assessed in terms of destruction and removal efficiency (DRE, %). Under the experimental conditions of PEG600/KOH/Al/100 oC/2hr, average DRE of PCBs was approximately 78%, showing completely removal of PCBs containing 7-9 chlorines on two rings of biphenyl which appear later than PCB no. 183 (2,2',3,4,4',5',6-heptaCB) in retention time of GC/ECD. However, when increasing the reaction temperature and time to 150 oC and 240 min, average DRE of PCBs including the most toxic PCBs (PCB no. 77, 105, 118, 123 and 169) in PCB family reached 99.99% or better, with the exception of PCB no. 5 and 8 (2,3-diCB and 2,4'-diCB). In studying the reaction of PEG with PCBs, it confirmed that the process led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines. The process also permits complete recovery of treated transformer oil through simple segregating procedures.

PCBs 함유 변압기 절연유의 화학적처리 (Chemical Treatment of the PCBs-laden Transformer Insulation Oil)

  • 유건상;최종하;최진환
    • 한국환경과학회지
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    • 제20권11호
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    • pp.1499-1507
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    • 2011
  • Practical disposal of transformer insulation oil laden with PCBs (polychlorinated biphenyls) by a chemical treatment has been studied in field work. The transformer insulation oil containing PCBs was treated by the required amounts of PEG (polyethylene glycol) and KOH, along with different reaction conditions such as temperatures and times. The reaction of PEG with PCBs under basic condition produces arylpolyglycols, the products of nucleophilic aromatic substitution. Removal efficiencies of PCBs in insulation oil before and after chemical treatment were examined. The removal efficiency of PCBs was very low at lower temperatures of 25 and $50^{\circ}C$. Under the reaction condition of PEG 600/KOH/$100^{\circ}C$/2hr, removal efficiency of PCBs was approximately 70%, showing completely removal of PCBs containing 7~9 chlorines on biphenyl frame which appear later than PCB IUPAC Number 183 (2,2',3,4,4',5',6-heptaCB) in retention time of GC/ECD. However, when increasing the reaction temperature and time to $150^{\circ}C$ and 4 hours, removal efficiency of PCBs reached 99.99% without any formation of PCDDS/PCDFs during the process. Such reaction conditions were verified by several official analytical institutions. In studying the reaction of PEG with PCBs, it confirmed that the process of chemical treatment led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines.

문자 영역을 강조하기 위한 적응적 오차 확산법 (Adaptive Error Diffusion for Text Enhancement)

  • 권재현;손창환;박태용;조양호;하영호
    • 대한전자공학회논문지SP
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    • 제43권1호
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    • pp.9-16
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    • 2006
  • 본 논문에서는 최대 기울기 차이(maximum gradient difference, MGD)를 이용한 효과적인 문자 분할과 문자 영역을 강조하기 위한 적응적 오차 확산법을 제안한다. 스캔 라인을 따라 기울기를 계산하고, 잠재적 문자 영역을 융합하기 위해 국부적 윈도우 내에 MGD 값을 채운다. 노이즈 필터링을 거친 후, 배경에는 기존 오차 확산법, 문자에는 경계 향상 오차 확산법을 적용한다. 서로 다른 하프토닝 알고리즘의 사용으로 눈에 거슬리는 결함이 발생하기 때문에 경계 결함을 줄이기 위해 단계적 팽창(gradual dilation)을 적용한다. 단계적으로 팽창된 문자 영역(gradually dilated to저 region, GDTR)에 기반한 샤프닝(sharpening)은 문자 영역의 경계에서 연속적으로 점이 찍히는 것을 막을 수 있다. 제안한 적응적 오차 확산법은 일반적인 오차 필터를 이용하여 경계 향상 정도를 조절할 수 있는 칼라 하프토닝 방법이다. 경계 향상 정도와 색차를 분석하여 경계 향상 계수를 정하고, 경계 향상 오차 확산법의 사용으로 인해 점이 찍히지 않는 결함을 줄이기 위하여 추가적인 오차 요소를 반영하였다. 스캔한 영상을 제안한 방법을 이용하여 하프토닝하면 배경의 변화 없이 문자 부분이 선명한 결과를 얻을 수 있다.

복호 신뢰도에 기반하여 점진적으로 보조정보를 향상시키는 변환영역 Wyner-Ziv 부호화 방법 (Transform domain Wyner-Ziv video coding with successively improving side information based on decoding reliability)

  • 고봉혁;심혁재;전병우
    • 방송공학회논문지
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    • 제13권6호
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    • pp.892-904
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    • 2008
  • 센서네트워크와 같은 자원한정적인 상황에서의 비디오 부호화가 중요해짐에 따라 경량화 비디오 부호화 문제의 솔루션으로 분산비디오 부호화 기술(DVC: Distributed Video Coding)이 폭넓게 연구되고 있다. 이의 대표적인 기술인 Wyner-Ziv 부호화 기술은, 복호화기에서 영상간 유사도를 이용하여 부호화하는 현재 프레임에 대한 보조정보를 생성하고, 발생하는 잡음을 채널코드를 이용하여 제거함으로써 영상을 복원한다. 따라서 복호화기에서 보조정보를 정교하게 만들수록, 즉 제거되어야 할 잡음이 적게 생성될수록 전체적인 시스템의 부호화 효율이 좋아진다. 하지만 실제로 복호화기가 부호화하는 현재 프레임에 대한 정보 없이 정확도 높은 보조정보를 만드는 것은 상당히 어려운 일이므로, 복호되는 현재 프레임의 정보 및 그 신뢰도에 기반하여 점진적으로 보조 정보를 향상시키는 방법이 개발되었다. 하지만 복호결과를 이용하여 보조정보를 향상시키기 위해서는 복호결과 정보의 에러율에 못지않게 복호결과로부터 유효한 정보의 양 또한 중요하다. 따라서 본 논문에서는 변환영역의 Wyner-Ziv 부호화 기술에서 점진적으로 복호되는 현재 프레임에 대한 정보의 에러율 및 유효한 정보 양을 고려한 신뢰도에 기반하여 점진적으로 보조정보를 향상시키는 부호화 방법을 제안한다. 실험결과는 제안 방법이 점진적 보조정보 향상방법을 사용하지 않는 이전 변환영역 Wyner-Ziv 부호화 방법에 비해 최대 약 1.7 dB에 이르는 성능향상이 있음을 보였다.