A cost-effective retrofit of conventional distillation sequence to dividing-wall prefractionator configuration

Minh, Le Quang,Pham, Tram Ngoc,Long, Nguyen Van Duc,Shin, Joonho,Lee, Moonyong Elsevier 2018 Computers & chemical engineering Vol.110 No.-

<P><B>Abstract</B></P> <P>A dividing-wall prefractionator configuration was investigated for a safe and economic retrofit of the conventional sequence using simple distillation columns. In the proposed retrofit configuration, the first column was modified to a dividing wall column as a prefractionator to supply prefractionated multi-feeds to the subsequent column. To investigate the effectiveness of the proposed configuration, nine near-ideal feed mixtures were considered for analysis. The proposed configuration was then compared with several other alternative configurations. The proposed dividing-wall prefractionator efficiently generates prefractionated multi-feed streams avoiding feed mismatch and remixing effect with low modification cost. Moreover, because the proposed retrofit configuration allows for flexible switching between the dividing-wall prefractionator and the conventional operating mode, a safe retrofit is also ensured by reducing the operational risks. Several industrial retrofit cases were studied to validate the proposed dividing-wall prefractionator configuration.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A dividing wall prefractionator configuration (DWPC) was studied for safe and cost-effective retrofit. </LI> <LI> A combined optimization method was proposed and applied for reliable design and fair comparison. </LI> <LI> Practical guideline was developed for the potential retrofit of DWPC. </LI> <LI> The performance of proposed DWPC was illustrated through several industrial cases. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

200 kV 용량형 분압기 2대를 이용한 교류 고전압 측정범위 확장

정재갑,이상화,강전홍,김명수,김윤형,한상길,정진혜,한상옥,정종만 대한전기학회 2008 전기학회논문지 P Vol.57 No.1

- The output voltage value of AC high voltage source has been usually obtained by multiplying low voltage value measured at both terminals of low voltage resistor by the dividing ratio of the high voltage capacitive divider. From the dividing ratio determined of each 200 kV capacitive divider, we have developed step-up method for measuring the output voltage up to 400 kV using two same type of 200 kV capacitive dividers connected in series. The theoretical dividing ratio of 400 kV capacitive dividers connected in series coincides with that of manufacturer's certification within measurement uncertainty. Thus, this developed step-up method makes it possible to extend the range of output voltage from 200 kV to 400 kV. Furthermore, The dividing ratio of divider under test obtained using this step-up method is consistent with that obtained using one 200 kV high voltage divider within corresponding uncertainties.

200 ㎸ 용량형 분압기 2대를 이용한 교류 고전압 측정범위 확장

鄭在甲(Jae-Kap Jung),李相和(Sang-Hwa Lee),姜銓洪(Jeon-Hong Kang),金明壽(Myung-Soo Kim),金潤亨(Yoon-Hyoung Kim),韓相吉(Sang-Gil Han),鄭辰慧(Jin-Hye Jeong),韓相玉(Sang-Ok Han),鄭鍾萬(Jong-Man Joung) 대한전기학회 2008 전기학회논문지 P Vol.57 No.1

The output voltage value of AC high voltage source has been usually obtained by multiplying low voltage value measured at both terminals of low voltage resistor by the dividing ratio of the high voltage capacitive divider. From the dividing ratio determined of each 200 ㎸ capacitive divider, we have developed step-up method for measuring the output voltage up to 400 ㎸ using two same type of 200 ㎸ capacitive dividers connected in series. The theoretical dividing ratio of 400 ㎸ capacitive dividers connected in series coincides with that of manufacturer's certification within measurement uncertainty. Thus, this developed step-up method makes it possible to extend the range of output voltage from 200 ㎸ to 400 ㎸, Furthermore. The dividing ratio of divider under test obtained using this step-up method is consistent with that obtained using one 200 ㎸ high voltage divider within corresponding uncertainties.

전기장 센서를 이용한 교류 400 kV 고전압 분압기의 제작 및 평가

이상화,한상길,정재갑,강전홍,김윤형,정진혜,한상옥 대한전기학회 2008 전기학회논문지 P Vol.57 No.3

Output voltage value of AC high voltage source has usually been obtained by measuring the low arm voltage of high voltage divider or the secondary voltage of high voltage transformer. In this study, we have fabricated the AC 400 kV high voltage divider using high voltage electrode and electric field measurement sensor. The dividing ratio of the fabricated 400 kV high voltage divider was evaluated using reference 400 kV capacitive divider. The dividing ratio of 400 kV high voltage divider is found to be 12,322 and has the good linearity within 0.63 % against AC high voltage up to 400 kV. Therefore, the developed 400 kV high voltage divider could evaluate 400 kV high voltage supply and voltage divider used in industry.

전기장 센서를 이용한 교류 400 ㎸ 고전압 분압기의 제작 및 평가

李相和(Sang-Hwa Lee),韓相吉(Sang-Gil Han),鄭在甲(Jae-Kap Jung),姜銓洪(Jeon-Hong Kang),金潤亨(Yoon-Hyoung Kim),鄭辰慧(Jin-Hye Jeong),韓相玉(Sang-Ok Han) 대한전기학회 2008 전기학회논문지 P Vol.57 No.3

Output voltage value of AC high voltage source has usually been obtained by measuring the low arm voltage of high voltage divider or the secondary voltage of high voltage transformer. In this study, we have fabricated the AC 400 ㎸ high voltage divider using high voltage electrode and electric field measurement sensor. The dividing ratio of the fabricated 400 ㎸ high voltage divider was evaluated using reference 400 ㎸ capacitive divider. The dividing ratio of 400 ㎸ high voltage divider is found to be 12,322 and has the good linearity within 0.63 % against AC high voltage up to 400 ㎸. Therefore, the developed 400 ㎸ high voltage divider could evaluate 400 ㎸ high voltage supply and voltage divider used in industry.

A New Approach for Hierarchical Dividing to Passenger Nodes in Passenger Dedicated Line

Chanchan Zhao,Feng Liu,Xiaowei Hai 한국정보처리학회 2018 Journal of information processing systems Vol.14 No.3

China possesses a passenger dedicated line system of large scale, passenger flow intensity with unevendistribution, and passenger nodes with complicated relations. Consequently, the significance of passengernodes shall be considered and the dissimilarity of passenger nodes shall be analyzed in compiling passengertrain operation and conducting transportation allocation. For this purpose, the passenger nodes need to behierarchically divided. Targeting at problems such as hierarchical dividing process vulnerable to subjectivefactors and local optimum in the current research, we propose a clustering approach based on self-organizingmap (SOM) and k-means, and then, harnessing the new approach, hierarchical dividing of passengerdedicated line passenger nodes is effectuated. Specifically, objective passenger nodes parameters are selectedand SOM is used to give a preliminary passenger nodes clustering firstly; secondly, Davies–Bouldin index isused to determine the number of clusters of the passenger nodes; and thirdly, k-means is used to conductaccurate clustering, thus getting the hierarchical dividing of passenger nodes. Through example analysis, thefeasibility and rationality of the algorithm was proved.

A New Approach for Hierarchical Dividing to Passenger Nodes in Passenger Dedicated Line

Zhao, Chanchan,Liu, Feng,Hai, Xiaowei Korea Information Processing Society 2018 Journal of information processing systems Vol.14 No.3

China possesses a passenger dedicated line system of large scale, passenger flow intensity with uneven distribution, and passenger nodes with complicated relations. Consequently, the significance of passenger nodes shall be considered and the dissimilarity of passenger nodes shall be analyzed in compiling passenger train operation and conducting transportation allocation. For this purpose, the passenger nodes need to be hierarchically divided. Targeting at problems such as hierarchical dividing process vulnerable to subjective factors and local optimum in the current research, we propose a clustering approach based on self-organizing map (SOM) and k-means, and then, harnessing the new approach, hierarchical dividing of passenger dedicated line passenger nodes is effectuated. Specifically, objective passenger nodes parameters are selected and SOM is used to give a preliminary passenger nodes clustering firstly; secondly, Davies-Bouldin index is used to determine the number of clusters of the passenger nodes; and thirdly, k-means is used to conduct accurate clustering, thus getting the hierarchical dividing of passenger nodes. Through example analysis, the feasibility and rationality of the algorithm was proved.

Leakage Current Effect of a Supporting Insulator on the Performance of a Resistive High-voltage

이상화,유광민,최장영,장석명 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.2

A new method is presented for measuring the insulation resistance of a Tefl on insulator in a resistive high-voltage divider, which is diffi cult when using the bridge or voltmeter methods. Our method determines the insulation resistance from the diff erence in the voltage dividing ratio before and after connecting calibrated high-ohm resistors to the Tefl on insulator in parallel. As the measurement results performed using this method, it is shown that the Tefl on’s insulation resistance, a support of a national dc high-voltage divider, is 5 × 10 14 to 2 × 10 15 Ω. This means that the leakage resistance eff ect on the voltage dividing ratio was less than 0.4 × 10 −6 , representing an insignifi cant impact on the divider’s performance.

빚에 대하여

구연상 한국하이데거학회 2011 현대유럽철학연구 Vol.0 No.25

This paper aims to systematically discover the meaning of a Korean word, “Bit(빚)”, which means “debt” in English. The literal meaning of the word “Bit(빚)” is “a thing that you have borrowed from someone else”, and this is derived from the relation between borrowing and lending. “Borrowing” also includes “begging”, which refers to asking someone to give me what I don’t have, or what I want. Borrowing is considered as the purpose of begging and it is lending that satisfies the purpose. Also, as “borrowing” gets its roots in “repaying”, its noun term “debt” also has a meaning of “something that you owe someone from necessity, on the condition of paying back later”. “Repaying”,however, means not only “returning something” that you have borrowed from somebody, but also doing so “with something”. According to this principle, the act “repaying” can be classified into three categories: Returning in kind as much as someone have borrowed(그대로-갚음), paying more than what one owes to the lender(길미-갚음), and working off in other kinds worth the debt(안-갚음). Both borrowing and repaying are achieved only if both borrower and lender trust each other. Here “trust” means the willingness to share all the burden and success with each other. “Sharing together”-under the condition that both truly believe each other-can be explained in the term “equally dividing(고루-나눔)” that includes “parity” as well as “equality”, all of which contribute to forming the meaning that “everyone has his or her own part without injustice to anyone”. This is enough to show “equally dividing” is based on the “rightness”. While “equally dividing” makes people live in a good harmony by sharing every burden and success, “unequal division” makes people grow apart from one another, as it applies a biased criteria to sharing. An “equally dividing” can be changed into “unequal division” at any time, all at once, through a certain social contract. The debt, as the thing to repay, gets to its meaning only when someone knows that he or she is indebted to someone else, and this is only possible when the person appreciates to the other. The expression “I appreciate it” or “Thank you” has a extra meaning that “I owe you.”We should be thankful to everything around us, as long as we know that we live in the world depending on them. It is not until we are aware of our duty in our life that we fully appreciate something, realize that we are making debts, and have a willingness to pay them back. Then we get to live our life to the full, in order to repay what I have owed to everything else. This can be summarized as the expression “Taking the responsibility for debts of your own making” and we should be willing to pay our debts back, taking it for the deed. In this way, my paper has shown affairs of our lives, through the consideration of the Korean term, “Bit(빚)”. 이 글은 한국말 “빚”의 의미를 체계적으로 밝히는 데 그 목적이있다. 빚의 일차적 의미는 ‘쓰기 위해 빌린 것’이다. 이는 빚이 ‘빌림과 빌려줌’의 관계를 통해 생겨난다는 것을 일컫는다. 빌림에는 빎이 속한다. 빎은누군가 자신에게 없거나 필요하거나 바라는 것을 남에게 달라고 하는 것이다. 빌림이 바로 빎의 목적이 된다. 빌려줌은 이러한 목적을 들어주는 것이다. 빌림의 본래적 뜻은 갚음에 있다. 빚은 ‘쓰기 위해 갚기로 하고 빌린 것’인 셈이다. 갚음은 ‘빌린-것-되돌리기’로서 ‘…을 …로써 갚는다’는 얼개로짜여 있다. 빚 갚음의 방식은 이 얼개에 따라 ‘그대로 갚음(대갚음, 앙갚음)’과 ‘길미 갚음’ 그리고 ‘안-갚음’ 등으로 나눌 수 있다. ‘그대로-갚음’은 빌린것을 빌린 것 자체로써 고스란히 되돌려 주는 것을 말하고, ‘길미-갚음’은‘빌린 것’을 그것에 길미를 덧얹은 ‘값’으로써 돌려주는 것을 말하며, ‘안-갚음’은 빌린 것 대신 그것에 값하는 행동을 하는 것을 말한다. 빚의 빌림과 갚음은 서로에 대한 믿음에 기초해서만 가능하고, 이때의 믿음은 빚을 통해 서로가 떠맡게 될 짐과 보람을 함께 나누고자 한다는 것을 뜻한다. 서로가 서로를 믿는 빌림에서의 ‘함께 나눔’은 ‘고루-나눔’이다. ‘고루-나눔’은 “균(均)”과 “등(等)”을 포괄적으로 뜻하는 개념으로 ‘모두가 저마다의 몫을 치우침 없이 가짐’을 뜻한다. 이는 ‘고루-나눔’이 올바름에 그 바탕을 두고 있음을 뜻한다. ‘고루-나눔’은 특정한 사회적 계약을 통해 ‘어긋-나누기(불균형)’가 될 수 있다. ‘고루-나누기’가 서로의 짐과 보람을 올바로 나눔으로써 사이를 좋게 만든다면, ‘달리-나누기’는 나눔의 잣대가 한쪽으로치우침으로써 사이를 벌어지게 만든다. 갚아야 할 것으로서의 빚은 누군가 자신이 ‘빚이 있다’는 사실을 깨달았을 때에만 빚이 된다. 사람은 고마움의 빛 가운데 자신에게 주어진 빚을 깨닫게된다. “나는 고맙다.”라는 말은 “나는 빚이 있다.”라는 뜻을 담고 있다. 하늘과 땅 그리고 그 사이에 있는 것은 모두, 우리가 그것들 덕분에 살아갈 수있는 한, 고마운 것이다. 빚을 깨달은 사람이 그 빚을 갚고자 할 때, 즉 그에게 갚아야 할 빚이 남아 있을 때, 그는 비로소 빚을 떠맡게 되고 빚을 짊어지게 되며 그 빚에 값하는 삶을 살 의무를 갖게 된다. 이것이 곧 ‘스스로빚지고 있음을 떠맡는 것’이다. 사람의 삶 전체가 빚에 의(依)한 것인 한 우리는 스스로의 빚을 깨닫고, 그 빚을 고맙게 갚아나가야 한다. 한국말 “빚”은이러한 삶의 사태를 드러낸다.

빚에 대하여

구연상 ( Gu Yeon-sang ) 한국하이데거학회 2011 존재론 연구 Vol.25 No.-

-이 글은 한국말 “빚”의 의미를 체계적으로 밝히는 데 그 목적이 있다. 빚의 일차적 의미는 ‘쓰기 위해 빌린 것’이다. 이는 빚이 ‘빌림과 빌려줌’의 관계를 통해 생겨난다는 것을 일컫는다. 빌림에는 빎이 속한다. 빎은 누군가 자신에게 없거나 필요하거나 바라는 것을 남에게 달라고 하는 것이다. 빌림이 바로 빎의 목적이 된다. 빌려줌은 이러한 목적을 들어주는 것이다. 빌림의 본래적 뜻은 갚음에 있다. 빚은 ‘쓰기 위해 갚기로 하고 빌린 것’인 셈이다. 갚음은 ‘빌린-것-되돌리기’로서 ‘…을 …로써 갚는다’는 얼개로 짜여 있다. 빚 갚음의 방식은 이 얼개에 따라 ‘그대로 갚음(대갚음, 앙갚음)’과 ‘길미 갚음’ 그리고 ‘안-갚음’ 등으로 나눌 수 있다. ‘그대로-갚음’은 빌린것을 빌린 것 자체로써 고스란히 되돌려 주는 것을 말하고, ‘길미-갚음’은 ‘빌린 것’을 그것에 길미를 덧얹은 ‘값’으로써 돌려주는 것을 말하며, ‘안-갚음’은 빌린 것 대신 그것에 값하는 행동을 하는 것을 말한다. 빚의 빌림과 갚음은 서로에 대한 믿음에 기초해서만 가능하고, 이때의 믿음은 빚을 통해 서로가 떠맡게 될 짐과 보람을 함께 나누고자 한다는 것을 뜻한다. 서로가 서로를 믿는 빌림에서의 ‘함께 나눔’은 ‘고루-나눔’이다. ‘고루-나눔’은 “균(均)”과 “등(等)”을 포괄적으로 뜻하는 개념으로 ‘모두가 저마다의 몫을 치우침 없이 가짐’을 뜻한다. 이는 ‘고루-나눔’이 올바름에 그 바탕을 두고 있음을 뜻한다. ‘고루-나눔’은 특정한 사회적 계약을 통해 ‘어긋-나누기(불균형)’가 될 수 있다. ‘고루-나누기’가 서로의 짐과 보람을 올바로 나눔으로써 사이를 좋게 만든다면, ‘달리-나누기’는 나눔의 잣대가 한쪽으로 치우침으로써 사이를 벌어지게 만든다. 갚아야 할 것으로서의 빚은 누군가 자신이 ‘빚이 있다’는 사실을 깨달았을 때에만 빚이 된다. 사람은 고마움의 빛 가운데 자신에게 주어진 빚을 깨닫게 된다. “나는 고맙다.”라는 말은 “나는 빚이 있다.”라는 뜻을 담고 있다. 하늘과 땅 그리고 그 사이에 있는 것은 모두, 우리가 그것들 덕분에 살아갈 수 있는 한, 고마운 것이다. 빚을 깨달은 사람이 그 빚을 갚고자 할 때, 즉 그에게 갚아야 할 빚이 남아 있을 때, 그는 비로소 빚을 떠맡게 되고 빚을 짊어지게 되며 그 빚에 값하는 삶을 살 의무를 갖게 된다. 이것이 곧 ‘스스로 빚지고 있음을 떠맡는 것’이다. 사람의 삶 전체가 빚에 의(依)한 것인 한 우리는 스스로의 빚을 깨닫고, 그 빚을 고맙게 갚아나가야 한다. 한국말 “빚”은 이러한 삶의 사태를 드러낸다. This paper aims to systematically discover the meaning of a Korean word, “Bit (빚)”, which means “debt” in English. The literal meaning of the word “Bit(빚)” is “a thing that you have borrowed from someone else”, and this is derived from the relation between borrowing and lending. “Borrowing” also includes “begging”, which refers to asking someone to give me what I don’t have, or what I want. Borrowing is considered as the purpose of begging and it is lending that satisfies the purpose. Also, as “borrowing” gets its roots in “repaying”, its noun term “debt” also has a meaning of “something that you owe someone from necessity, on the condition of paying back later”. “Repaying”, however, means not only “returning something” that you have borrowed from somebody, but also doing so “with something”. According to this principle, the act “repaying” can be classified into three categories: Returning in kind as much as someone have borrowed(그대로-갚음), paying more than what one owes to the lender(길미-갚음), and working off in other kinds worth the debt(안-갚음). Both borrowing and repaying are achieved only if both borrower and lender trust each other. Here “trust” means the willingness to share all the burden and success with each other. “Sharing together”-under the condition that both truly believe each other-can be explained in the term “equally dividing(고루-나눔)” that includes “parity” as well as “equality”, all of which contribute to forming the meaning that “everyone has his or her own part without injustice to anyone”. This is enough to show “equally dividing” is based on the “rightness”. While “equally dividing” makes people live in a good harmony by sharing every burden and success, “unequal division” makes people grow apart from one another, as it applies a biased criteria to sharing. An “equally dividing” can be changed into “unequal division” at any time, all at once, through a certain social contract. The debt, as the thing to repay, gets to its meaning only when someone knows that he or she is indebted to someone else, and this is only possible when the person appreciates to the other. The expression “I appreciate it” or “Thank you” has a extra meaning that “I owe you.” We should be thankful to everything around us, as long as we know that we live in the world depending on them. It is not until we are aware of our duty in our life that we fully appreciate something, realize that we are making debts, and have a willingness to pay them back. Then we get to live our life to the full, in order to repay what I have owed to everything else. This can be summarized as the expression “Taking the responsibility for debts of your own making” and we should be willing to pay our debts back, taking it for the deed. In this way, my paper has shown affairs of our lives, through the consideration of the Korean term, “Bit(빚)”.