• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.1-7
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• 2014

A stretchable polymeric membrane shaped diffuser was used to homogenize the coherent laser beam. The developed RGB module was used to focus and defocus test by beam combiners. Average oscillation frequency was set at 180Hz~300Hz and it resulted in the best homogenization effect in visual range. The blue laser module turned out to be the worst case for the transmission and primary reason is believed to be the short length of irradiated laser beam. The developed system removed the speckling and the brightness was decreased by 10 ~ 20% for the RGB laser. Overall the brightness was decreased by 13% and homogenity with respect to the temporal axis was improved from 30fs to 110fs.

• Toxicological Research
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• v.24 no.1
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• pp.1-9
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• 2008

Ptdlns(4,5)$P_2$ is a key cellular phosphoinositide that localizes in separate and distinctive pools in subcellular membrane and vesicular compartments. In membranes, Ptdlns(4,5)$P_2$ acts as a precursor to second messengers and is itself a main signaling and targeting molecule. Specific subcellular localization of type I PIP kinases directed by interacting with specific targeting module differentiates Ptdlns(4,5)$P_2$ production in a spatial and temporal manner. Several lines of evidences support the idea that Ptdlns(4,5)$P_2$ is generated in very specific pools in a spatial and temporal manner or by feeding Ptdlns(4,5)$P_2$ directly to effectors. In this concept, the interaction of PIPKI isoforms with a specific targeting module to allow precise subcellular targeting modulates highly specific Ptdlns(4,5)$P_2$ synthesis and channeling overall effectors. For instance, localization of PIPKI${\gamma}$661 to focal adhesions by an interaction with talin results in spatial and temporal production of Ptdlns(4,5)$P_2$, which regulates EGF-stimulated directional cell migration. In addition, Type $I{\gamma}$ PIPK is targeted to E-cadherin in cell adherence junction and plays a role in controlling dynamics of cell adherence junction and endocytosis of E-cadherin. Characterizing how PIP kinase isoforms are regulated by interactions with their targeting modules, as well as the mechanisms by which their product, Ptdlns(4,5)$P_2$, exerts its effects on cellular signaling processes, is crucial to understand the harmonized control of numerous cellular signaling pathways. Thus, in this review the roles of the Ptdlns(4)P(5) kinases and Ptdlns(4,5)$P_2$ were described and critically reviewed in terms of regulation of the E-cadherin trafficking, cell migration, and formation of cell adherence junction which is indispensable and is tightly controlled in epithelial-to-mesenchymal transition process.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.3
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• pp.51-59
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• 2003

In this study, the efficiency of M/F(micro filtration) system was investigated about the wastewater generated from the production process of ${\beta}-glucan$. M/F membrane used the pellicon 2 cassette filter module of millipore(USA) for the operation of M/F plant system. Flux was rised as operation pressure increased, and decreased with the operation time. As concentration ratio increased, the recovery of ${\beta}-glucan$, which was remaind in retentate was effective. As the fermentation solution of ${\beta}-glucan$ reused, the conversion ratio was 42.5%, and the status of fermentation was stable. Based on these results, we suggested that permeate was applicable as water reuse in cleaner production technology.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.11
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• pp.607-618
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• 2015

This study was conducted to suggest hydraulic modification for improving evenness of inlet flow distribution into side stream type low-pressure MF (microfiltration) module using CFD (computational fluid dynamics) simulation and PIV (particle image velocimetry) techniques. From the results of CFD simulation for various typed inlet structure, it was investigated that installing internal orifice baffle in inlet the distribution channel could improve the evenness of inlet flow distribution over about 40%. Also, from the results of PIV measurements which were carried out for verifying the CFD simulation, it was observed that the momentum of the water body coming from the opposite side of the inlet was relatively larger. This momentum would generate strong shear force in the near of inlet side wall. On the other hands, occurrence of dead zone and eddy flow was confirmed in the opposite side.

• Journal of the Society of Disaster Information
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• v.16 no.2
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• pp.383-391
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• 2020

Purpose: To identify internal self ignition and ignition caused by external flames in energy storage rooms, and to analyze the difference between ignition due to overheating and ignition caused by external heat sources. Method: membrane melting point measurement, battery external hydrothermal experiment, battery overcharge experiment, comparative analysis of electrode plate during combustion by overcharge and external heat, overcharge combustion characteristics, external hydrothermal fire combustion characteristics, 3.4 (electrode plate comparison) / 3.5 (overcharge) /3.6 (external sequence) analysis experiment. Result: Since the temperature difference was very different depending on the position of the sensor until the fire occurred, it is judged that two temperature sensors per module are not enough to prevent the fire through temperature control in advance. Conclusion: The short circuit acts as an ignition source and ignites the mixed gas, causing a gas explosion. The electrode breaks finely due to the explosion pressure, and the powder-like lithium oxide is sparked like a firecracker by the flame reaction.

• Membrane and Water Treatment
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• v.1 no.3
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• pp.207-214
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• 2010

Approximately 80% of water used in urban areas reappears as municipal wastewater (MWW). Reclamation of MWW is an attractive proposition under the present scenario of water stressed cities in India. In this paper, we attempted to reclaim MWW using lab-scale hollow- fiber (HF) membrane modules for possible reuse in non-potable applications. Experiments were conducted to evaluate the efficiency of virgin HF ($M_1$) and modified HF ($M_2$) modules. The $M_2$ module consists of HF modified with a skin layer formed through interfacial polymerization of m-phenylenediamine with trimesoyl chloride (MPD-TMC). The molecular weight cut-off (MWCO) of $M_1$ was 44000 g/mol and that of $M_2$ 10000 -14000 g/mol on the basis of rejection of polyethylene glycol. The combination of $M_1$ and $M_2$ modules was able to reduce concentrations of most of the pollutants in sewage and improved the treated water quality to the acceptable limits for non potable reuse applications. It is found that about 98-99% of the initial flux is recovered by the backwashing process, which was approximately two times in a month when operated continuously.

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.563-567
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• 1999

Reverse osmosis concentration for cephalosproin C was studied using a polyamide composite membrane, FT-30 in spiral wound type with high solute rejection. The experiments were carried out in the aqueous solution of cephalosporin C for water flux, solute rejection and mass transfer coefficient under applied pressure of $4{\sim}20kg/cm^2$, feed concentration of 100~1000 mg/L and feed velocity of 2.8 and 5.6 L/min at room temperature. The effect of operating pressure on the separation of cephalosporin C showed that permeate flux increased with increasing operation pressure. These results are consistent with those predicted by Kedem-Katchalsky model. Solute rejection was nearly 1. The increase of feed concentration caused the reduction of cephalosporin C rejection, which was higher at low concentration than at high concentration, but degree of reduction was small.

• Journal of Korean Society of Water and Wastewater
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• v.32 no.4
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• pp.317-324
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• 2018

SWRO-PRO hybrid desalination technology is recently getting more attention especially in large desalination markets such as USA, Middle East, Japan, Singapore, etc. because of its promising potential to recover a considerable amount of osmotic energy from brine (a high-concentration solution of salt, 60,000 - 80,000 mg/L) and also to minimize the impact of the discharged brine into a marine ecosystem. By the research and development of the core technologies of the SWRO-PRO desalination system in a national desalination research project (Global MVP) supported by Ministry of Land, Infrastructure, and Transport (MOLIT) and Korea Agency for Infrastructure Technology Advancement (KAIA), it is anticipated that around 25% of total energy consumption rate (generally 3 to $4kWh/m^3$) of the SWRO desalination can be reduced by recovering the brine's osmotic energy utilizing wastewater treatment effluent as a PRO feed solution and an isobaric pressure exchanger (PX, ERI) as a PRO energy converter. However, there are still several challenges needed to be overcome in order to ultimately commercialize the novel SWRO-PRO process. They include system optimization and integration, development of efficient PRO membrane and module, development of PRO membrane fouling control technology, development of design and operation technology for the system scaling-up, development of diverse business models, and so on. In this paper, the current status and progress of the pilot study of the newly developed SWRO-PRO hybrid desalination technology is discussed.

• Journal of Sensor Science and Technology
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• v.23 no.3
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• pp.178-184
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• 2014

Key components of implantable hearing aids are consist of an acoustic sensor that collect external sound by suppressing the body noise, a signal processor module for compensation algorithm of hearing loss, and a output transducer which has tiny size but have high efficiency, respectively. In the partial implantable hearing aids, technologies of transducer and signal processor are so matured that can be applied not too much difficulty. However, due to the difficulties in implantable acoustic sensor technology, such as minimization of masticatory sound and damage of sensor's membrane from external impact, practical use of fully implantable hearing aids have not successful so far. In this paper, we have proposed a novel implantable acoustic sensor which has trans-tympanic structure, and is verified that the proposed method can be very useful for fully implantable hearing aids by cadaveric experiments.

• Membrane Journal
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• v.7 no.2
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• pp.75-83
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• 1997

The disc plate and frame type modules for reverse osmosis were developed using three different types of baffles: linear (Type 1), curved (Type 2) and parallel shapes (Type 3). Separation performance tests were carried out for the modules using NaCl and sucrose solutions under the various concentrations and operating pressures. The permeation flux and solute rejection ratio for Type 3 module were the highest within operating pressure (35bar) and flow rate (6 l/min). The flux improvement ratio of Type 2 or 3 to Type 1 for NaCl solution decreased as operating pressure increased: flux improvement ratios of Type 3 for 1wt% of NaCl solution were about 100 and 10% at 10 and 35bar, respectively. However, the flux improvement ratio for sucrose solutions varied with the operating pressure and concentration. The permeation flux for Type 3 depended on the flow rate linearly, which is higher than that of turbulent flow region in the smooth channel.