• 제목/요약/키워드: Contribution rate

검색결과 868건 처리시간 0.027초

섬유상활성탄(纖維狀活性炭)에 의한 유기화합물(有機化合物)의 흡착특성(吸着特性)(II) (Adsorption Characteristics of Organic Compounds on the Activated Carbon Fiber(II))

  • 손진언;이시원
    • Elastomers and Composites
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    • 제24권2호
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    • pp.105-109
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    • 1989
  • ACF을 이용한 컬럼흡착에서 유기물의 액상흡착을 크로마토그래피에 의하여 측정하였다. 박테리아가 없는 상태에서의 텍스트로스의 흡착평형상수 Ka는 $72.5cm^3/g$이었으며 박테리아 공존상에서의 Ka값은 $87.9cm^3/g$을 나타내였다. 이것은 ACF상(床)의 박테리아의 존재가 유기물의 흡착평형상수 증가에 기여함을 알 수 있었다. 축방향혼합확산계수 Ez는 박테리아의 유무에 의존하지 않았다.

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샅바잡기 유형별 동작 시 상지근육의 근활동치 비교 분석 (Analysis of Muscle Activities for Upper Extremity According to Satbar-Grip Patterns)

  • 김태완;황규연;김정석
    • 한국운동역학회지
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    • 제16권3호
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    • pp.95-103
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    • 2006
  • The purpose of this study was to analyze a change of maximal grip forces and EMG of agonists in upper extremity of 8 professional Ssirum players according to Satbar-grip patterns, to elucidate prime agonist muscles, contribution rate of each muscle, and a difference on EMG in upper extremity. one-way ANOVA(RM) performed for average and maximal values of each player after standardization and statistical significance was set as p<.05. The result includes the following: the highest grip force was A type with a statistic significance using one-way ANOVA and Duncan's comparison between A and C type. In summary the highest grip force was exerted on extension in the wrist than flexion in all grip types. Average and maximal values of biceps brachii and brachioradialis muscles were statistically significant and ones of flexor carpi ulnaris and extensor capi ulnaris were not.

고강도 콘크리트 내화성능 보강인자의 최적반응조건 도출을 위한 정준분석 모델 기준 (Fire Resistance of High Strength Concrete Canonical Analysis Standard for Optimal Response Condition)

  • 김영훈;이문환;이세현;유종수;전준영;류득현
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.227-228
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    • 2009
  • 본 연구는 80MPa급 고강도콘크리트를 적용한 건축물의 화재시 성능확보를 위한 보강인자 배합사용에 있어 효율적인 내화성능 및 시공성을 확보하기 위한 최적배합비를 도출하고자 하였다. 이를 위한 분석 방법인 반응표면분석을 이용한 과정을 통하여 내화보강인자간의 최적공정조건 도출시 각 물성의 한계 값 설정에 따른 최적배합의 타당성을 검토하고자 하였다.

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Phonon Dispersion이 열전달 모델에 미치는 영향 (Impact of Phonon Dispersion on Thermal Conductivity Model)

  • 정재동
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1627-1632
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    • 2003
  • The effect of (1) phonon dispersion in thermal conductivity model and (2) the differentiation of group velocity and phase velocity for Ge is examined. The results show drastic change of thermal conductivity regardless of using same relaxation time model. Also the contribution of transverse acoustic (TA) phonon and longitudinal acoustic (LA) phonon is changed by considering more rigorous dispersion model. Holland model underestimates the scattering rate for high frequency TA, so misleading conclusion, i.e. TA is dominant heat transfer mode at high temperature. But the actual reduction of thermal conductivity is much larger than the estimation by Holland model and high frequency TA is no more dominant heat transfer mode. Another heat transfer mechanism may exist for high temperature. Two possible explanations are (1) high frequency LA by Umklapp scattering and (2) optical phonon.

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신생아의 산-염기 균형과 대사성 산증 (Acid-base Balance and Metabolic Acidosis in Neonates)

  • 이병섭
    • Neonatal Medicine
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    • 제17권2호
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    • pp.155-160
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    • 2010
  • Metabolic acidosis is commonly encountered issues in the management of critically ill neonates and especially of preterm infants during early neonatal days. In extremely premature infants, low glomerular filtration rate and immaturity of renal tubules to produce new bicarbonate causes renal bicarbonate loss. Higher intake of amino acids, relatively greater contribution of protein to the energy metabolism and mineralization process in growing bones are also responsible for higher acid load in premature infant than in adult. Despite widespread use of sodium bicarbonate in the management of severe metabolic acidosis, use of sodium bicarbonate in premature infants should be restricted to a reasonable but unproven exception such as ongoing renal loss. Despite concern about the low pH value (<7.2) which can compromise cellular metabolic function, no treatment guideline has been established regarding the management of metabolic acidosis in premature infants. Appropriately powered randomized controlled trials of base therapy to treat metabolic acidosis in critically ill newborn infants are demanding.

Feature Selection Algorithms in Intrusion Detection System: A Survey

  • MAZA, Sofiane;TOUAHRIA, Mohamed
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권10호
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    • pp.5079-5099
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    • 2018
  • Regarding to the huge number of connections and the large flow of data on the Internet, Intrusion Detection System (IDS) has a difficulty to detect attacks. Moreover, irrelevant and redundant features influence on the quality of IDS precisely on the detection rate and processing cost. Feature Selection (FS) is the important technique, which gives the issue for enhancing the performance of detection. There are different works have been proposed, but a map for understanding and constructing a state of the FS in IDS is still need more investigation. In this paper, we introduce a survey of feature selection algorithms for intrusion detection system. We describe the well-known approaches that have been proposed in FS for IDS. Furthermore, we provide a classification with a comparative study between different contribution according to their techniques and results. We identify a new taxonomy for future trends and existing challenges.

Simple formulas for the fuel of climbing propeller driven airplanes

  • Labonte, Gilles
    • Advances in aircraft and spacecraft science
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    • 제2권4호
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    • pp.367-389
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    • 2015
  • Simple solutions are obtained for the fuel required by internal combustion engine airplanes on trajectories with a constant rate of climb or descent. Three modes of flight are considered: constant speed, constant Mach number and constant angle of attack. Starting from the exact solutions of the equations of motion for the modes of motion considered, approximate solutions are obtained that are much easier to compute while still being quite precise. Simpler formulas are derived for the weight of fuel, speed, altitude, horizontal distance, time to climb, and power required. These formulas represent a new important contribution since they are fundamental for the analysis of aircraft dynamics and thus have direct applications for the analysis of aircraft performances and mission planning.

Spectrofluorometric Study of the Interaction of Coumarin Derivatives with Bovine Serum Albumin

  • Kamat, B.P.;Seetharamappa, J.;Kovala-Demertzi, D.
    • Journal of Photoscience
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    • 제11권2호
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    • pp.65-69
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    • 2004
  • The mechanism of interaction of four coumarin derivatives (CDS) with bovine serum albumin (BSA) was studied using spectrofluorometric technique. It was found that the coumarin ring common to all CDS makes major contribution to interaction. Binding affinities could be related to parachor values of CDS. Stem-Volmer plots indicated the presence of static component in the quenching mechanism. Results also showed that both tryptophan residues of protein are accessible to CDS. The high magnitude of rate constant of quenching indicated that the process of energy transfer occurs by intermolecular interaction forces and thus CDS binding site is in close proximity to tryptophan residues of BSA. Binding studies in the presence of the hydrophobic probe, 8-anilino-l-naphthalein-sulfonic acid showed that there is hydrophobic interaction between CDS and the probe and they do not share common sites in BSA. Thermodynamic parameters obtained from data at different temperatures showed that the binding of CDS to BSA involve hydrophobic bonds predominantly. The effects of various metal ions on the binding of CDS with BSA were also investigated.

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완속여과 공정에서 전처리 공정 도입에 따른 입자제거 효율평가 (Evaluation of particulate removal in slow sand filtration processes)

  • 김성수;배철호;박노석;강석형
    • 상하수도학회지
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    • 제22권4호
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    • pp.461-466
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    • 2008
  • Because of their simplicity, efficiency, and economy, slow sand filters are appropriate means of water treatment for small water systems. In this study, the effect of filtration velocity and dirty skin (Schmutzdecke) was evaluated on the performance of turbidity removal. Also, removal characteristics of particulate were investigated in the case of the usage of non-woven fabric on the surface of sand and the application of PCF as pretreatment process. Comparative column tests were carried out for the various operation condition. From the result of column tests, filtration velocity had little effect on the turbidity removal rate. The formation of algal biofilm on the surface of media is helpful in turbidity removal, while non-woven fabric is not as effective as expected. The relative contribution of biomass and accumulated particulates to head loss development in slow sand filters requires further study.

Stuttgart 콘크리트 보 전단실험의 재해석을 통한 합리적 전단모델 연구 (A Study on the Rational Shear Model by interpretation of Stuttgart Beam Shear Test)

  • 김우;모귀석;정제평
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.884-889
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    • 2003
  • Based on the reinterpretation of the well-known relationship between shear and the rate of change of bending moment in a reinforced concrete beam subject to combined shear and moment loads, the shortcomings of present truss models are discussed. The core of the theory is that a new perspective on the shear strength can be gained by viewing the internal stress filed in terms of the superposition of two base components of shear resistance; arch action and beam action. The arch action can be designed using the simple truss having curved compression chord, while the beam action between the two chords can be modeled using a parallel chord truss with MCFT or RA-STM. The compatibility of deformation associated to the two action is taken into account by employing a characteristic factor a. The new model was examined by the Stuttgart beam shear tests, and the results show that the present approach provides good estimates of stirrup contribution and concrete contributions.

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