• Title/Summary/Keyword: FASs

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Sorption Characteristics of Butanol/Water and Isopropanol/Water Solutions on the FASs Coated Inorganic Membrane (FASs로 코팅한 무기막에 대한 부탄올/물, 이소프로판올/물 용액의 수착 특성)

  • Lee, Kwang-Rae
    • Membrane Journal
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    • v.28 no.5
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    • pp.320-325
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    • 2018
  • The sorption amounts of butanol/water and isopropanol/water solution on the surface modified with FASs (fluoroalkylsilanes) hydrophobic membrane were measured and analyzed using Hansen's solubility parameters. The difference of the solubility parameter of butanol (${\delta}_t=20.4$) and that of the surface modified with FASs hydrophobic membrane (${\delta}_t=16.9$) was greater than the case of isopropanol (${\delta}_t=24.6$), which might explain the result that the sorption amount of butanol was much higher than that of isopropanol. We might also explain the effect of the polar force (${\delta}_p$) on the sorption amount. The difference (${\Delta}$) between FASs polar force (${\delta}_p=4.6$) and butanol polar force (${\delta}_p=6.3$) was much smaller than that between FASs polar force (${\delta}_p=4.6$) and isopropanol polar force (${\delta}_p=9.0$), which meant that the interaction of butanol-FASs was much greater than that of isopropanol-FASs, and resulted in greater sorption amount of butanol on the FASs. This study showed Hansen's solubility parameters might be used for analysis of sorption characteristics of alcohol on membrane and solubility of solute in solvent.

A Study on Even Distribution of Workloads Using Simulated Annealing Method on Integrated Layout Design in Cellular flexible Assembly Systems (셀형 유연조립시스템에서 작업부하 균형을 고려한 통합 배치설계에 관한 연구)

  • 정지용;노인규
    • Journal of the Korean Operations Research and Management Science Society
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    • v.23 no.4
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    • pp.63-73
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    • 1998
  • With the success of flexible manufacturing systems(FMSs), flexible assembly systems(FASs) have been developed to automatic factories further. As in a cellular FMS, a celluar FAS is considered as the most flexible and feasible assembly systems configuration. This paper presents a method for the integrated layout design in cellular FASs. Unlike the traditional paper, this paper deals with the formation of cells and the layout of cells for jobs with operation times on different machines. The procedure in this paper consists of two distinct phases. The first phase presents machine arrangement in a double rows flowline. cell formation not to allow intercellular movements, and integrated layout design in cellular FASs considering the characteristics of FAS, layout, and production factors This phase uses older optimal algorithm. The second phase proposes to balance the system with an objective of reducing the degree of workload deviation in the cells. Simulated annealing method is used to balance the system. This phase also shows the integrated layout design in cellular FASs with the cost less than total cost of the first phase.

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Meaning and Conceptual Tension Contained in the Definition of Social Services Prescribed by Recently Amended Framework Act on Social Security (개정 사회보장기본법의 사회서비스의 의미와 개념적 긴장)

  • Nam, Chan-Seob
    • Korean Journal of Social Welfare
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    • v.64 no.3
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    • pp.79-100
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    • 2012
  • This paper aims to analyze the meaning and conceptual tension contained in the definition of social services prescribed by recently amended Framework Act on Social Security(FASS) by examining various terminologies of social services in Korea. In Korea the term of social services has had at least four meanings since it has begun to be used during Participatory Government. Of these, the meaning of social services in FASS is closest to 'social serives as social-jobs'. While, as has this meaning, social services in FASS is defined as very comprehensive one, it also has its conceptual tension. On the one hand, FASS comes to have the orientation to include immensely wide fields such as welfare, health, employment, housing, culture and environment within social service. However on the other hand FASS still has the orientation to limit social services to traditional social welfare services. Unless re-amending the recently amended FASS, the conceptual tension resulted from these two conflicting orientations will be likely to continue. And this might raise the need both to reform the organization of Ministry of Health and Welfare and exiting delivery systems of social services and to develop theoretical and practical principles providing basis for tailored social services, which in turn poses important challenges to social welfare discipline. To meet these challenges it is necessary to cooperate between micro and macro approaches.

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Prediction of Affinity between Membrane and Esters Using Solubility Parameter (용해도 파라미터에 의한 막과 esters 간의 친화도 예측)

  • Song, Kun-Ho;Lee, Kwang-Rae
    • Membrane Journal
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    • v.24 no.6
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    • pp.484-490
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    • 2014
  • To find out the feasibility of the separating/enriching esters from aqueous solution using FASs (Fluoloalkyl-silanes-coupling agent)-surface modified hydrophobic membrane, the solubility parameter of FASs was obtained and compared with those of esters and water. The value of the solubility parameter of FASs (${\delta}_t=16.9$) was almost same with those of esters (ethyl acetate ${\delta}_t=18.1$, propyl acetate ${\delta}_t=18.0$, ethyl propionate ${\delta}_t=17.9$, butyl acetate ${\delta}_t=17.4$, ethyl butyrate ${\delta}_t=17.0$). However, the calculated value of the solubility parameter of water was ${\delta}_t=47.8$, which was far from the value of the solubility parameter of FASs (${\delta}_t=16.9$). This means that the FASs-modified membrane has a much higher affinity to esters than water. The experimental results of permeation flux of esters used in this study showed that the order of permeation flux predicted by the solubility parameter was almost coincide with experimental results. It might be concluded that the solubility parameter may be applicable for a separating/enriching flavors from aqueous natural-flavor solution, in which esters are main components of natural flavors.

Network-type Cell Layout in Cellular Flexible Assembly Systems (셀형유연조립시스템에서의 네트웍형 셀배치)

  • 노인규;최형호
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.19 no.39
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    • pp.63-73
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    • 1996
  • With the success of flexible manufacturing systems (FMSs), flexible assembly systems (FASs) have been developed to automate factories further. As in a cellular FMS, a cellular FAS is considered as the most flexible and feasible assembly system configuration Because of the differences between manufacturing and assembly operation, the logic of cell formation and cell layout between a FMS and a FAS is not the same. Since the time for assembly operation is usually relatively short, the transfer time is thus very crucial for the performance of assembly systems. Therefore in assembly systems it is important to reduce the transfer time by sequencing operations efficiently and arranging machines like the sequences. The network-type layout is not only feasible for the machine arrangement based on operation sequences, but it has also layout flexibility. Therefore it is a reasonable layout configuration for cellular FASs. This paper presents a method for the cell layout based on the network-type layout in a cellular FAS design.

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Integrated Layout Design in Cellular Flexible Assembly Systems (셀형 유연조립시스템에서의 통합 배치설계)

  • 최영호;노인규
    • Journal of the Korean Operations Research and Management Science Society
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    • v.22 no.4
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    • pp.133-149
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    • 1997
  • The major two steps required to design a cellular layout are cell formation and cell layout. Because of the differences between manufacturing and assembly operations, the logic of cell formation and cell layout between an FMS and an FAS is not the same. Since the time for the assembly operations is usualaly relatively short, the transfer time is thus very crucial for the performance of assembly systems. Transfore in a cellular FAS it is more important to eliminate backtracking operations in assembly planning, not to allow intercellular movements in cell formation, and to arrange machines according to assembly sequence in cell layout. This study presents a method for the integrated layout design in cellular FASs considering the characteristics of FAS, layout, and production factors.

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The Influence of Simple Electrolyte on the Behaviour of Some Acid Dyes in Aqueous Media

  • M. M. El-Fass;N. A. Badawy;A. A. El-Bayaa;N. S. Moursy
    • Bulletin of the Korean Chemical Society
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    • v.16 no.5
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    • pp.458-461
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    • 1995
  • The influence of adding counter-ion such as Na+ on the dimerization of the two sulphonated azo dyes, C.I. Acid Red 14 and C.I. Acid Red 17 in aqueous media has been studied spectrophotometrically. The observed hypochromic effect on increasing the amount of salt has been described. The dye concentration range where the dimerization equilibrium is applicable was chosen. No metachromatic behaviour was observed on changing the dye concentration and the amount of salt. This behaviour was attributed to the ability of the counter-ion to disrupt the structure of water as well as reducing the electrostatic repulsion forces between dye anions which will lead to the increase of aggregation tendency of the dye species.

Effects of Free Alkali and Moisture on Sucrose Polyesters Synthesis (유리 알카리 및 수분이 sucrose polyesters 합성에 미치는 영향)

  • Chung, Ha-Yull;Kim, Suk-Ju;Yoon, Sung-Woo;Yoon, Hee-Nam;Kong, Un-Young
    • Korean Journal of Food Science and Technology
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    • v.24 no.3
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    • pp.247-250
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    • 1992
  • Effects of free alkali and moisture on sucrose polyesters (SPE)-possible non calorie fat substitute-synthesis were investigated using a model system composed of sodium oleate, sucrose, potassium carbonate and methyl oleate. Trace amounts of free alkali in sodium oleate were found to interefere with SPE synthesis. When free alkali content in sodium oleate was varied gradually from 0% to 5%(w/w), the yield of SPE production was reduced from 92% to 45.5%. The moisture absorbed in sodium oleate, sucrose and potassium carbonate during storage also interefered with SPE synthesis. The yield (92%) of SPE production with dried ($105^{\circ}C$.6 hrs) reactants and catalysts was higher than that (89%) of SPE production with non-dried. Soybean oil fatty acid sodium soaps (FASS) not containing free alkali could be manufactured with slightly less than molar ratio of sodium hydroxide to soybean oil fatty acid methyl esters (FAME). Practically, 91.7% yield of soybean oil SPE production was outcomed by minimizing free alkali and moisture which were remaining in sucrose, potassium carbonate, soybean oil FASS and soybean oil FAME.

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A Multiobjective Process Planning of Flexible Assembly Systems with Evolutionary Algorithms (진화알고리듬을 이용한 유연조립시스템의 다목적 공정계획)

  • Shin, Kyoung Seok;Kim, Yeo Keun
    • Journal of Korean Institute of Industrial Engineers
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    • v.31 no.3
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    • pp.180-193
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    • 2005
  • This paper deals with a multiobjective process planning problem of flexible assembly systems(FASs). The FAS planning problem addressed in this paper is an integrated one of the assignment of assembly tasks to stations and the determination of assembly routing, while satisfying precedence relations among the tasks and flexibility capacity for each station. In this research, we consider two objectives: minimizing transfer time of the products among stations and absolute deviation of workstation workload(ADWW). We place emphasis on finding a set of diverse near Pareto or true Pareto optimal solutions. To achieve this, we present a new multiobjective coevolutionary algorithm for the integrated problem here, named a multiobjective symbiotic evolutionary algorithm(MOSEA). The structure of the algorithm and the strategies of evolution are devised in this paper to enhance the search ability. Extensive computational experiments are carried out to demonstrate the performance of the proposed algorithm. The experimental results show that the proposed algorithm is a promising method for the integrated and multiobjective problem.

Role of endoscopy in gastroesophageal reflux disease

  • Daniel Martin Simadibrata;Elvira Lesmana;Ronnie Fass
    • Clinical Endoscopy
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    • v.56 no.6
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    • pp.681-692
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    • 2023
  • In general, gastroesophageal reflux disease (GERD) is diagnosed clinically based on typical symptoms and/or response to proton pump inhibitor treatment. Upper gastrointestinal endoscopy is reserved for patients presenting with alarm symptoms, such as dysphagia, odynophagia, significant weight loss, gastrointestinal bleeding, or anorexia; those who meet the criteria for Barrett's esophagus screening; those who report a lack or partial response to proton pump inhibitor treatment; and those with prior endoscopic or surgical anti-reflux interventions. Newer endoscopic techniques are primarily used to increase diagnostic yield and provide an alternative to medical or surgical treatment for GERD. The available endoscopic modalities for the diagnosis of GERD include conventional endoscopy with white-light imaging, high-resolution and high-magnification endoscopy, chromoendoscopy, image-enhanced endoscopy (narrow-band imaging, I- SCAN, flexible spectral imaging color enhancement, blue laser imaging, and linked color imaging), and confocal laser endomicroscopy. Endoscopic techniques for treating GERD include esophageal radiofrequency energy delivery/Stretta procedure, transoral incisionless fundoplication, and endoscopic full-thickness plication. Other novel techniques include anti-reflux mucosectomy, peroral endoscopic cardiac constriction, endoscopic submucosal dissection, and endoscopic band ligation. Currently, many of the new endoscopic techniques are not widely available, and their use is limited to centers of excellence.