• Title/Summary/Keyword: separation index

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Enantioselective Membranes Based on Chitosan for The Separation of D- And L-Tryptophan

  • Jonggeon Jegal;Kim, Jang-Hoon;Kim, Jee-Hye;Lee, Kew-Ho;Lee, Yongtaek
    • Korean Membrane Journal
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    • v.5 no.1
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    • pp.25-30
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    • 2003
  • Chitosan membranes crosslinked with glutaraldehayde that contained chiral environment were prepared. The chitosan membranes were characterized using FTIR and swelling index measurements. Their swelling index in water ranged from 100 to 70%, depending on the crosslinking time. The separation of D- and L-isomers of tryptophan was achieved through a pressure driven membrane separation process, using the self-supporting crosslinked chitosan membranes. The chiral separation performance of the membranes depended strongly on the swelling index of the membranes and the separation conditions such as concentration of feed solutions and different operating pressures. Especially when a chitosan membrane with a swelling index of 70% was used, almost complete optical resolution of D- and L-tryptophan was obtained ; enantiomeric excess (ee %) of 97.92% and flux of 2.26 g/㎡$.$h.

A Study on the Characteristics of Cross-contamination according to the Size and Separation distance of Exterior Air-vents (실외 급배기구 크기와 이격거리에 따른 교차오염 특성연구)

  • Moon, Yong-Jun;Noh, Kwang-Chul;Oh, Myung-Do
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.393-398
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    • 2006
  • This study is undertaken to evaluate the characteristics of cross contamination around exterior air-vents. A CFD analysis has been performed to calculate the cross contamination index for five exterior air-vents sizes according to the outdoor air velocity and separation distance of it. From the result of the numerical method, As the outdoor air velocity is increased, the cross contamination index is increased. on the contrary, as the separation distance of exterior air-vents is increased, the cross contamination index is decreased, additionally the cross contamination is affected by the aspect ratio of the size of exterior Air-vents.

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A Study on an Algorithm of Line Switching and Bus Separation for Alleviating Overloads by the Use of Line Power Tracing and Sensitivity (선로유효전력 Tracing과 민감도를 활용한 선로 과부하 해소 스위칭 및 모선분리 알고리즘에 관한 연구)

  • Lee, Byung-Ha;Hwang, Sung-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.11
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    • pp.2007-2016
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    • 2011
  • In this paper, a new algorithm for alleviating overloads in power networks by the use of line power tracing and sensitivity is proposed to perform line switching and bus separation effectively. Also, a new bus separation index based on line power tracing is presented to find the bus to be separated for relieving overloads effectively. By applying the sensitivity of the line flow with respect to the change of the line impedance, both switching-on and switching-off of the lines for alleviating overloads in power networks are performed systematically at once. The number of the considered cases for line switching and bus separation can be greatly reduced and the best combination of line switching and bus separation can be acquired efficiently by the use of the sensitivity and the bus separation index. In order to show the effects of this algorithm, it is applied to a small scale power system of IEEE 39-bus system and practical power systems of KEPCO.

A Cluster Validity Index Using Overlap and Separation Measures Between Fuzzy Clusters (클러스터간 중첩성과 분리성을 이용한 퍼지 분할의 평가 기법)

  • Kim, Dae-Won;Lee, Kwang-H.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.13 no.4
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    • pp.455-460
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    • 2003
  • A new cluster validity index is proposed that determines the optimal partition and optimal number of clusters for fuzzy partitions obtained from the fuzzy c-means algorithm. The proposed validity index exploits an overlap measure and a separation measure between clusters. The overlap measure is obtained by computing an inter-cluster overlap. The separation measure is obtained by computing a distance between fuzzy clusters. A good fuzzy partition is expected to have a low degree of overlap and a larger separation distance. Testing of the proposed index and nine previously formulated indexes on well-known data sets showed the superior effectiveness and reliability of the proposed index in comparison to other indexes.

Better Bootstrap Confidence Intervals for Process Incapability Index $C_{pp}$

  • Cho, Joong-Jae;Han, Jeong-Hye;Lee, In-Pyo
    • Journal of the Korean Data and Information Science Society
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    • v.10 no.2
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    • pp.341-357
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    • 1999
  • Greenwich and Jahr-Schaffrath(1995) considered a new process incapability index(PII) $C_{pp}$, which modified the useful index $C^{\ast}_{pm}{$ for detecting assignable causes. The new index $C_{pp}$ provides an uncontaminated separation between information concerning the process accuracy and precision while this kind of information separation is not available with the $C^{\ast}_{pm}$ index. In this paper, we will study about the index $C_{pp}$ based on the bootstrap. First, we will prove the consistency of bootstrap deriving the bootstrap asymptotic distribution for our index $C_{pp}$. Moreover, with the consistency of bootstrap, we will construct six bootstrap confidence intervals and compare their performances. Some simulation results, comparison and analysis are provided. In particular, two STUD and ABC bootstrap methods perform significantly better.

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Effect of Emulsion Treatment on the Separation of Quick-Cooking Rice Kernel and the Quality of Reconstituted Rice (즉석건조쌀밥의 건조후 밥알분리 및 품질에 미치는 에멀젼처리 효과)

  • Lee, Tae-Hun;Park, Jung-Hee;Kim, Dong-Min;Rhim, Jong-Whan
    • Korean Journal of Food Science and Technology
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    • v.23 no.5
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    • pp.593-598
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    • 1991
  • The effect of emulsion treatment on the separation of quick-cooking rice kernel after drying and the quality of reconstituted quick-cooking rice made of a Japonica variety were investigated. Among the several stages of emulsion treatment tested, immersion of cooked rice before drying was the most effective on the separation index. Immersion condition of 3 min at $30^{\circ}C$ was found to be the most desirable. Emulsion composed of 5% soybean oil and 0.5% sucrose fatty acid ester (HLB : 9.5) was found to be the most effective to yield the separation index of 86%. By applying the above mentioned emulsion, the separation index was improved by 30 compared with untreated one. The quality of the quick-cooking rice manufactured by the emulsion treatment was found to be as good as untreated one.

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A Study on Process Incapability Measure for Non-Normal Process: $C^*_{psk}$TEX> (비정규공정에 대한 비공정능력 측도에 관한 연구: $C^*_{psk}$)

  • 채규용;이상용
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.21 no.48
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    • pp.233-240
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    • 1998
  • Recently, Hong-Jun Kim et al. introduced an improved process incapability index $C^*_{psk}$ by the transformation of the $C_{psk}{\;}C^*_{psk}$. A simple transformation of $C_{psk}$, can be regard as a process incapability index, provides an uncontaminated separation between information concerning the process accuracy and precision while this kind of information separation is not available with the $C_{psk}$. By an identical conception, in this article a new process incapability index $C^*_{psk}$ for Non-Normal process can be proposed by the transformation of the process capability index $C^*_{psk}$. The motivation behind introduction of $C^*_{psk}$ is that process capability index $C^*_{psk}$ cannot give information of the process accuracy and precision. A significant result of this research that $C^*_{psk}$ for the case where the target value T is equal to the midpoint of the specification limits or not Is evaluated without respect to T. Accordingly, $C^*_({psk})$ will be propose a reasonable process incapability measure for Non-Normal process

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A Measure of Process Incapability Index (비공정능력지수의 측도에 관한 연구)

  • 김진수;김홍준;송서일
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.22 no.49
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    • pp.77-87
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    • 1999
  • A simple transformation of the $C^{*}$$_{pm}$, $C_{pp}$ can be regard as a process incapability index, provides an uncontaminated separation between information concerning the process accuracy and precision while this kind of information separation is not available with the $C^{*}$$_{pm}$. Recently, Kyung-seok Shin et. al. introduced an improved process incapability index $C^{*}$$_{pmk}$ by the transformation of the $C_{pmk}$. Accordingly, in this article process incapability index $C^{*}$$_{psk}$ will be proposed by the transformation of the $C_{psk}$. The motivation behind introduction of $C^{*}$$_{psk}$ is that $C_{psk}$ has failed to overcome is that it cannot distinguish process of high conforming output proportions from those of low conforming output proportions. Process incapability index $C^{*}$$_{psk}$ can identify a difference between two things by comparison on $C_{psk}$ and $C^{*}$$_{psk}$.EX>$_{psk}$.EX>$_{psk}$.

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