• Environmental Engineering Research
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• v.19 no.4
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• pp.395-399
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• 2014

Operation characteristics of the sequencing batch reactor (SBR) process with electro-flotation (EF) as a solid liquid separation method (EF-SBR) were investigated. EF-SBR process showed excellent solid-liquid separation performance which enabled to separate biosolids from liquid phase within 30 min and to extend cyclic reaction time. Although influent organic loading rate was increased stepwise from 5 to 15 g COD/day, food to microorganisms (F/M) ratio could be maintained about 0.3 g COD/g VSS/day in EF-SBR because biomass concentration could be easily controlled at desired level by EF. However, it was impossible to increase biomass concentration at the same level in control SBR (C-SBR) process because solid-liquid separation by gravity settling showed a limitation at higher mixed liquor suspended solids (MLSS) concentration with 60 min of settling time. Total chemical oxygen demand (TCOD) removal efficiency of EF-SBR process was not decreased although influent organic loading rate became 3 times higher than initial value. However, it was seriously deteriorated in C-SBR process after increasing the rate over 10 g COD/day, which was accounted for insufficient organic removal by relatively higher food to microorganisms (F/M) ratio as well as biosolids wash-out by a limitation of gravity sedimentation.

• Journal of Life Science
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• v.8 no.5
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• pp.504-508
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• 1998

A study was conducted to evaluate a protein removal characteristics by foam separation. The foam separator was operated in well-mixed tank which would be considered as a completely mixed condition. The feasibility of foam separation to remove protein from fresh and sea water was investigated. Protein removal characteristics of the foam separator were obtained by batch reactor operations. To find the effect of the operating parameter to protein removal rate, the foam separation was carried with variation of initial protein concentration and foam height. The results indicated that the protein removal efficiency was increased with increasing protein concentration and decreased with increasing foam height. The relationship between protein concentration and protein removal rate was evaluated by linear regression.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.218-219
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• 2008

A gas-liquid centrifugal separator is widely used in industry because of its simple geometry and little maintenance. Also, these separators have considerable advantages over filters, scrubbers or precipitators in term of compact design, low pressure drop and higher capacity. A gas-liquid centrifugal separator is a device that utilizes centrifugal force and low pressure to separate liquid from gas by density difference. Design parameters such as length of separation space, swirl vane exit angle, inlet to outlet pipe diameter ratio, models for separation efficiency and low pressure drop as a function of physical dimension are not available in literature. In present study, length of separation space (from vane to gas exit opening) has been studied using CFD. The 3-D Navier-Stokes equations are numerically solved using a fully implicit finite volume scheme. Based upon the obtained solutions, tangential velocities, centrifugal forces, vortices and total pressure losses are analyzed to find the best design parameters.

• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.519-523
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• 2006

Poly(dimethyl siloxane) (PDMS) has been employed as a microchip material for DNA separation in microfluidic condition. Different sieving molecules such as cellulose derivatives having glucose building block (methyl cellulose (MC), hydroxyethyl cellulose (HEC), and hydroxypropyl methyl cellulose (HPMC)) and polyethylene oxide (PEO) having linear (ring-opened ethylene oxide) unit were used and their performance was compared in terms of separation efficiency and resolution. In general, PEO showed better separation performance than cellulose derivatives probably due to the nature of linear shape polymer conformation. It was possible to perform at least 15 consecutive running with 1.2% PEO at the electric field strength around 200 V/cm. Fast analysis of the standard $\Phi$X 174 RF DNA/Hae III (less than 130s) was obtained with the number of the theoretical plate around 250,000/m. Our PMDS microchip was applied to the measurement of CAG repeat number, which is related to male infertile disease.

• East Asian Journal of Business Economics (EAJBE)
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• v.2 no.1
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• pp.1-6
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• 2014

This research was about understanding challenges in managing a business start up. University of Kigali was used as a case study. It is domiciled in Rwanda. It was chosen because it is a recent university establishment and it provided a good source of information for this research. The issue that triggered this study was to understand the virtue of having clear separation of duties in new business start-ups. The findings from this study reveal that 100 percent of the respondents believe that clear separation of roles and clear communication between management, shareholders and Board of directors is vital for new businesses. From the Literature review, it was clear that a firm in its infancy has a lot of risks and it would not be a bad idea for the start for shareholders and Board of directors to give a helping hand in the day to day running of the business until its stabilization. Employees need to know the vision and mission of the business start-up and again, the managing director of a firm needs to work closely with the chairman Board of directors for effective driving of the firm into the right direction. The momentum in growth of University of Kigali is due to respect of the pillar of separation of duties in its hierarchical structure and for allowing a decentralized structure type of management for flourish.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.2
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• pp.117-122
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• 2010

BCY($Ba(Ce_{0.9}Y_{0.1})O_{3-\delta}$) oxide, shows high protonic conductivity at high temperatures, and are referred to as hydrogen separation membrane. For high efficiency of hydrogen separation ($H_2$ flux and selectivity) and low fabrication cost, ultimate thin and dense BCY-Ni layer have to be coated on a porous substrate such as $ZrO_2$. Aerosol depostion (AD) process is a novel technique to grow ceramic film with high density and nano-crystal structure at room-temperature, and would be applied to the fabrication process of AD integration ceramic layer effectively. XRD and SEM measurements were conducted in order to analyze the characteristics of BCY-Ni membrane fabricated by AD process.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.49-52
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• 2009

This paper aims to evaluate hydration and intensity property of different kind of members and intensity in order to evaluate compressive strength of structural concrete using Joint Separation Test Body(JSTB). In fact it is difficult to test and evaluate already have constructed member. In this case, common method used by construction engineer is that ; Schmidt rebound hammer test, Ultrasonic pulse test, Method of using test specimen previously cast. However, these method to control the structural intensity involve many problem and impossibility to adapt construction. 80, this paper proposes advance an opinion which have proper to examine intensity. has also aims to examine its validity and the plan to make similar environment with structural concrete and joint separation test body in order to verify efficiency assessment and on-site application.

• Journal of Energy Engineering
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• v.8 no.4
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• pp.533-539
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• 1999

Integration methods of a Gas Turbine and a Air Separation Unit have a potential to improve plant performance and cost of IFCC. Several studies on those integrations schemes were carried out. Then some of the methods were accually in commercial plants. Thus paper reviewed the integration schemes of a Gas Turbine and a Air Separation Unit. In order to compare the plant performance of IGCC with each scheme, simulation model was developed for IGCC power cycle with Texaco Quench gasification process. The simulation results showed that the thermal efficiency of the plant was appeared to be the best when all of the air consumption required for Air Separation Unit was supplied from the Gas Turbine and the net plant power output was maximized when 75% of the total ASU an requirement was supplied from Gas Turbine.

• Journal of Radiation Industry
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• v.9 no.2
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• pp.77-84
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• 2015

The stainless steel mesh coated with poly(acrylic acid) hydrogel was fabricated and applied for the separation of water and oil. The stainless steel mesh was immersed in aqueous poly (acrylic acid) solution, and then irradiated by radiation to introduce poly(acrylic acid) hydrogel on the surface of mesh by crosslinking. It was possible to separate oil and water from mixtures of oil/water effectively using the hydrogel-coated mesh. The effect of irradiation dose, coating thickness, size of mesh on the separation efficiency was examined.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.416-424
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• 2018

Oil spill and oily wastewater have now become a serious threat to the freshwater and marine environments. Porous materials with super-hydrophobicity and super-oleophilicity are good candidates for the oil adsorption and oil/water separation. Here, flexible hybrid nanofibrous membrane (FHNM) containing $SiO_2$/polyvinylidene fluoride (PVDF) microspheres was prepared by simultaneous electrospinning and electrospraying. The obtained FHNM combined the flexibility of the nanofiber mat and super-hydrophobicity of the microspheres, which could not be achieved by either only electrospinning or only electrospraying. It was found that when the weight ratio between the $SiO_2$ and PVDF reached a critical value, the $SiO_2$ nanoparticles were present on the PVDF microsphere surface, significantly improving the surface roughness and hence the contact angle of the FHNM. Compared with the pure electrospun PVDF nanofiber mat, most of the FHNMs have a higher oil adsorption capacity. The FHNM could separate the oil with water quickly under the gravity and displayed a high efficiency and good reusability for the oil/water separation. More importantly, the FHNM could not only separate the oil with the pure water but also the corrosive solution including the salt, acid and alkali solution.