• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.747-754
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• 2006

Real-time traffic information disseminated through VMS is known to have effects not only on driver to plan a route choice, detour the congestion, and cope with incident, but also on VMS operator to manage the traffic volume indirectly. But, the dissemination of traffic information is operated in the side of provider, not of user. Importance-Performance analysis (IPA) offers a simple, useful method for simultaneously considering both the importance and performance dimensions when evaluating or improving strategy. This technique has been successfully used in a variety of settings to define priorities and guide resource optimization decisions. This study uses IPA to evaluate traffic information strategies through VMS to make resource improvement recommendations. It gained 760 samples by field surveys, which are conducted in Korean Thanksgiving Day, weekday and weekend at the service areas of expressways. The results indicate that the motivations in quadrant I (concentrate here) are dissemination of exactly information and quick transmission, while distance of VMS, most drivers are not satisfied with that is located in quadrant III (low priority).

• Transportation Technology and Policy
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• v.7 no.3
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• pp.109-118
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• 2010

• Proceedings of the Membrane Society of Korea Conference
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• 2000.11a
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• pp.104-106
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• 2000

• Membrane Journal
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• v.17 no.1
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• pp.61-66
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• 2007

A zeolite membrane shows better thermal, mechanical and chemical stabilities than a polymer membrane. Water was separated from iso-propyl alcohol (IPA)/water mixtures by pervaporation using the NaY zeolite membrane synthesized in the laboratory. The effects of a mole fraction of IPA in the feed solution and an operating temperature were studied on the permeation flux behavior and the separation factor of water with respect to IPA. As a mole fraction of IPA increased, the water flux as well as the separation factor decreased. As the experimental temperature increased, the water permeation flux increased while the separation factor decreased. For IPA/water binary mixtures, the water flukes through the NaY zeolite membrane were observed to be $1.9{\times}10^2{\sim}3.5{\times}10^3\;g/m^2{\cdot}hr$ and the separation factors were found to be $7.0{\times}10^2{\sim}2.0{\times}10^4$.

• The Journal of the Korea Contents Association
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• v.13 no.3
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• pp.392-401
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• 2013

This study was conducted to research the Selection Attribute for Pension which is located in the region of S. Gyeonggi-do. We intended to find the best choice point for reserving the pension using IPA and suggest or provide strategic implications and marketing method for running the pension. The survey was conducted from the early January to the end of March in 2012 with one to one method. A total of 300 questionnaires were distributed and 229 responded questionnaires were reliable to be used as a sample. The result of the survey was analyzed by using SPSS 15.0 version for window with Paired t-test and IPA method. Frequency Analysis was also conducted for the characteristic of samples. Findings are presented and discussed in three areas. First, the cleanliness of rooms, service for customer, heating and cooling system are the key important factors for the choice of pensions. Secondly, all factors are statistically significant level(p<0.01, p<0.001) as a results of performing IPA method. Thirdly, the result has shown that the varity of programs in the pension have significant impact on the customers' choice and satisfaction.

• Membrane Journal
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• v.16 no.1
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• pp.25-30
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• 2006

The NaA zeolite membrane was synthesized on the surface of a porous ${\alpha}$-alumina support from the reaction solution composed of 1Si : 1Na : 4Na $6H_{2}O$. The pervaporation performance of the synthesized NaA zeolite membrane was investigated for the iso-propyl alcohol (IPA) aqueous solution according to the different feed concentration and the different operating temperature. The total flux decreases by increasing the feed IPA concentration and increases by increasing the temperature. The total flux was about $4.0{\times}10^3g/m^2\;hr\;at\;60^{\circ}C$ and 0.6 mole fraction of IPA and the separation factor was $1.8{\times}10^7\;at\;60^{\circ}C$ and 0.8 mole fraction of IPA. The separation performance of water through the NaA membrane was found to be superior to that obtainable with a distillation process just by comparison of the vapor-liquid equilibrium data.

• Nutrition Research and Practice
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• v.17 no.4
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• pp.616-630
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• 2023

BACKGROUND/OBJECTIVES: Indole-3-propionic acid (IPA) is a tryptophan-derived microbial metabolite that has been associated with protective effects against inflammatory and metabolic diseases. However, there is a lack of knowledge regarding the effects of IPA under physiological conditions and at the intestinal level. MATERIALS/METHODS: Human intestinal epithelial Caco-2 cells were treated for 2, 24, and/or 72 h with IPA or its precursors - indole, tryptophan, and propionate - at 1, 10, 100, 250, or 500 μM to assess cell viability, integrity, differentiation, and proliferation. RESULTS: IPA induced cell proliferation and this effect was associated with a higher expression of extracellular signal-regulated kinase 2 (ERK2) and a lower expression of c-Jun. Although indole and propionate also induced cell proliferation, this involved ERK2 and c-Jun independent mechanisms. On the other hand, both tryptophan and propionate increased cell integrity and reduced the expression of claudin-1, whereas propionate decreased cell differentiation. CONCLUSIONS: In conclusion, these findings suggested that IPA and its precursors distinctly contribute to the proliferation, differentiation, and barrier function properties of human intestinal epithelial cells. Moreover, the pro-proliferative effect of IPA in intestinal epithelial cells was not explained by its precursors and is rather related to its whole chemical structure. Maintaining IPA at physiological levels, e.g., through IPA-producing commensal bacteria, may be important to preserve the integrity of the intestinal barrier and play an integral role in maintaining metabolic homeostasis.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.1
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• pp.102-108
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• 2006

On the refutation demanded for a control of various toxic substances. PCBs(poly chlorinated biphenyl) has a fatal poisonous matter in the ecosystem and the environmental pollution as it Is a kind of stable chemical substance. Especially, the gross Product of PCBs is estimated at about one million tonnage all over the world. However it is kept on storing in untreated state, then has a deterioration by the Prolonged storage and a risk of overflowing. Therefore, this research examined the fundamental characteristics of combustion and emission for the target of using the IPA (iso-propyl alcohol) solution as a part of PCBs control. IPA was filled to three kinds of Vessel, i.e. Vessel I, II, and III, and then was investigated as follows combustion shape, flame temperature. mass burning velocity, and PM(Particulate matter). A radial thermometer and a C-A thermocouple measured the flame temperature, and the optical extinction method by using He-Ne laser and the filter weight method used in the PM measurement. As a result, with an increasing of L/S ratio, the flame length become shorter and the burning velocity is more rapid, but the particulate matters is higher. It is supposed that the air flow rate is high on Vessel. and then the combustion is Promoted in the surface area of the upstream zone. The future works plan to investigate the characteristics with an using of the mixing of IPA and PCBs

• Textile Coloration and Finishing
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• v.17 no.3 s.82
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• pp.34-42
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• 2005

In this work, a practical separation performance was investigated on aqueous alcohol solutions, especially for iso-propyl alcohol (IPA), which is usually used during the semi- conductor rinsing process. The removal of various substances from waste aqueous IPA solutions was carried out by microfiltration with $0.1\~1{\mu}$m pore size of mean diameter as a pre-filter. Permeability and molecular weight cut-off of the functional polysulfone(PSf) ultrafiltration membrane to purify waste aqueous IPA solutions were measured through the ultrafiltration test. The solute rejection of PSf membrane had $92\%$ in 1,000ppm aqueous PEG solution with PEG molecular weight 10,000, the molecular weight cut-off had 10,000. The IPA concentration on the $CMPA-K^+$ membrane performance using pervaporation module system could be increased from $95.04 wt\%$ to more than $98.50wt\%$ in about 9hr at operation temperature of $70^{\circ}C$ using the pervaporation module system.

• Journal of the Korean Society of Food Culture
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• v.28 no.2
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• pp.195-203
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• 2013

The aim of this study was to provide strategic implications for the coffee market in which competition got severer through IPA analysis based on the attributes of selection of a specialized franchise coffee shop. The results of a positive analysis conducted with undergraduates in their twenties were as follows: According to the evaluation of the importance of the attributes of selection of a specialized coffee shop, the most important were 'cleanliness and hygienic facilities inside the shop (6.09)' and 'taste and quality of the menu (coffee) (6.09)'. According to the performance analysis, those showing the highest performance were 'brand image (4.92)' and 'cleanliness and hygienic facilities inside the shop (4.92)'. According to the result of IPA analysis, what customers regarded as being the most important were 'taste and quality of the menu (coffee)', 'kindness of the staff', and 'cleanliness and hygienic facilities inside the shop', and, in fact, they showed great performances as well. However, 'price of the menu (coffee)' was regarded as being important but did not indicate a great performance; therefore, they showed dissatisfaction with it. Although they did not think 'environment around the shop', 'brand image', 'brand recognition' or 'interior size and scale of the shop' were important, the attributes did not appear to show great performances. Therefore, we need constant maintenance strate gies regarding the fact that consumers are considered to be very important for evaluation, and should make efforts to change the price in advance.