• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.293-296
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• 2002

Hyperosmotic pressure increased specific antibody productivity ($q_{Ab}$) of recombinant CHO cells (SH2-0.32) while it depressed cell growth. Thus, the use of hyperosmolar medium did not increase the maximum antibody concentration substantially. To overcome this drawback, the feasibility of biphasic culture strategy was investigated. In the biphasic culture, cells were first cultivated in the standard medium with physiological osmolality(294 mOsm/kg) for cell growth. When cells reached the late exponential phase of growth, the spent standard medium was replaced with the fresh hyperosmolar medium (522 mOsm/kg) for antibody production. The ($q_{Ab}$) in growth phase with the standard medium was 2.1 ${\mu}g/10^6cell/day$ while the ($q_{Ab}$) in antibody production phase with the hyperosmolar medium (522 mOsm/kg) was 11.1 ${\mu}g/10^6cell/day$. Northern blot analysis showed a positive relationship between the relative contenet of Ig mRNA and ($q_{Ab}$), indicating that transcriptional regulation was involved in the response of rCHO cells to hyperosmotic pressure. Due to the enhanced ($q_{Ab}$) and increased cell concentration in biphasic culture, the maximum antibody concentration obtained in biphasic culture with 522 mOsm/kg medium exchange was 161% higher than that obtained in batch culture with the standard medium. Taken together, simple biphasic culture strategy based on hyperosmotic culture for improved foreign protein production from rCHO cells is effective in improving antibody production of rCHO cells.

• Journal of Sensor Science and Technology
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• v.24 no.1
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• pp.10-14
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• 2015

This paper reports the results of a study on the optimization of the etching profile, which is an important factor in deep-reactive-ion etching (DRIE), i.e., dry etching. Dry etching is the key processing step necessary for the development of the Internet of Things (IoT) and various microelectromechanical sensors (MEMS). Large-area etching (open area > 20%) under a high-frequency (HF) condition with nonoptimized processing parameters results in damage to the etched sidewall. Therefore, in this study, optimization was performed under a low-frequency (LF) condition. The HF method, which is typically used for through-silicon via (TSV) technology, applies a high etch rate and cannot be easily adapted to processes sensitive to sidewall damage. The optimal etching profile was determined by controlling various parameters for the DRIE of a large Si wafer area (open area > 20%). The optimal processing condition was derived after establishing the correlations of etch rate, uniformity, and sidewall damage on a 6-in Si wafer to the parameters of coil power, run pressure, platen power for passivation etching, and $SF_6$ gas flow rate. The processing-parameter-dependent results of the experiments performed for optimization of the etching profile in terms of etch rate, uniformity, and sidewall damage in the case of large Si area etching can be summarized as follows. When LF is applied, the platen power, coil power, and $SF_6$ should be low, whereas the run pressure has little effect on the etching performance. Under the optimal LF condition of 380 Hz, the platen power, coil power, and $SF_6$ were set at 115W, 3500W, and 700 sccm, respectively. In addition, the aforementioned standard recipe was applied as follows: run pressure of 4 Pa, $C_4F_8$ content of 400 sccm, and a gas exchange interval of $SF_6/C_4F_8=2s/3s$.

• Applied Chemistry for Engineering
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• v.22 no.2
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• pp.209-213
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• 2011

Hydrophobic silica aerogel beads with low thermal conductivity and high porosity were prepared using a cost-effective sodium silicate as a silica source via an ambient-pressure drying process. Monolithic wet gels were first prepared by adjusting pH (~5) of a diluted sodium silicate solution. The silica aerogel beads (0.5~20 mm) were manufactured by breaking the wet gel monoliths under a simultaneous solvent exchange/surface modification process and an ambient-pressure drying process without using co-precursors or templates. Dried silica aerogel beads exhibit a comparable porosity ($593m^2/g$ of surface area, 34.9 nm of pore size, and $4.4cm^3/g$ of pore volume) to that of the aerogel powder prepared in the same conditions. Thermal conductivity of the silica aerogel beads (19.8 mW/mK at $20^{\circ}C$) is also identical to the aerogel powder.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.131-137
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• 2010

Recently, many domestic golf course have showed interest in introducing new cultivars into existing putting greens without reconstruction. But, any report and survey method for interseeding substitute ratio haven't been published. Therefore, this study was conducted to evaluate the effectiveness for interseeding by investigating how many interseeding plants were introduced into existing putting green by using molecular biologic tool. The Woo Jung Hills Country Club was one time introduced penn A4 into penncross putting green. The Lake Side Country Club was three times introduced CY-2 into penncross putting green. The interseeding substitute ratio using SCAR markers was 20% in the Woo Jung Hills Country Club and 35.5% in Lake Side Country Club. The interseeding putting green in Lake Side Country Club was investigated to three site, strong pressure, middle pressure and weak pressure. These substitute ratios were strong pressure 27.1%, middle pressure 37.3%, and weak pressure 47.2%. The data indicated that an interseeding substitute ratio was more increased three times than one time to introducing new cultivar into existing putting green. A long-term program should be made in order to exchange existing cultivar in putting green without reconstruction.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.404-409
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• 2014

In this study, the effects of high-pressure homogenizer treatment on the physicochemical properties of wheat bran from different areas were evaluated. The results showed that the high-pressure homogenizer process could effectively decrease particle size and loosen the microstructure of the wheat bran matrix. As the particle size decreased, the bulk density of wheat bran was significantly decreased (p<0.05) and the water-holding capacity, swelling capacity, oil-holding capacity, and cation-exchange capacity were substantially increased. In addition, microscopic analysis revealed the gradual disintegration of the original cell wall structure and the dissociation of bran tissues over the course of high-pressure homogenization treatment. Scanning electron micrographs showed that the process could also effectively separate out the structural components of wheat bran. These results suggest that the high-pressure homogenizer process is an effective method to modify the physicochemical properties of wheat bran and likely other cereal brans, which might provide potential fiber-rich ingredients for use in functional foods.

• Tuberculosis and Respiratory Diseases
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• v.73 no.4
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• pp.197-203
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• 2012

Recent advances in bronchoscopy have led to changes in clinical diagnostics and therapeutics in pulmonary medicine. In diagnostic bronchoscopy, there have also been new developments in endobronchial ultrasound technology which may be incorporated into clinical practice in the near future. Functional bronchoscopy, which evaluates information such as airway pressure, airflow, or gas exchange, suggests promising clinical advances in the near future. In therapeutic bronchoscopy, bronchoscopic volume reduction is a novel approach for the treatment of severe emphysema. In this review, seven recently published articles representing current advances in bronchoscopy are summarized and discussed.

• Korean Journal of Artificial Intelligence
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• v.7 no.1
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• pp.13-16
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• 2019

While the Chinese banks have started the impact of foreign banks. At the same time, rising pressure on foreign exchange reserves and appreciation of the renminbi has prompted Chinese banks to go abroad and diversify their risks. The financial crisis of 2008 has caused the continued turbulence of the major financial markets around the world, and the valuation of foreign financial institutions has been drastically shrinking, providing opportunities for Chinese banks to carry out overseas M&A. Based on the overseas M&A status of Chinese commercial banks, this paper sums up the characteristics of the overseas M&A. Then taking a series of overseas M&A conducted by ICBC from 2006 to 2011 as an example, it analyzes the relationship between M&A and performance growth using grey incidence model. The test shows: there is a positive correlation between both overseas M&A and interest rate differential with performance growth of ICBC, and overseas M&A transactions role in promoting the performance growth is significantly higher than the interest rate differential.

• YAKHAK HOEJI
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• v.29 no.3
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• pp.144-151
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• 1985

Cathodic stripping voltammetric determination of traces of selenium in plant samples was studied. Stripping peak of selenium (IV) from Cu-Se intermettalic deposit in acidic media containing copper (II) ion is specific, highly sensitive and well defined, is successfully used for the quantitative determination of selenuin down to the level of 1ng/ml. Sample is burnt in a calorimeter bomb under the oxygen pressure of 40atm. and the selenium is absorbed in 0.1M NaOH. After the solution is filtrated, concentrated and acidified with HCl, then passed through a column of cation exchange resin in the $H^{+}$ form(Dowex 50X-8). The column eluate is analyzed for selenium by differential pulse cathodic stripping voltammetric method. Analytical results of selenium for NBS SMR is well agreement with the certified values. Results are given for a series of plant materials.

• Journal of the korean Society of Automotive Engineers
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• v.12 no.3
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• pp.30-40
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• 1990

The computer program for the prediction of the volumetric efficiency of 4-cycle single cylinder diesel engine was developed using the characteristic method which considers the effects of friction, heat transfer and specific heat. The results of calculation by this program are as follows; 1. The back flowing was arised at the beginning and the closing stage of inlet valve, and the back flowing mass and velocity decrease as the engine speed increases. 2. The volumetric efficiency varies with the engine speed and the length of inlet manifold. There was an optimum length of inlet manifold for each specified engine speed. 3. The pressure fluctuation and friction effect in the inlet manifold became very important factors for the determination of the volumetric efficiency.

• 한국전산유체공학회:학술대회논문집
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• 2004.03a
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• pp.161-165
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• 2004

In the vortex particle method based on the vorticity-velocity formulation for solving the Wavier-Stokes equations, the unsteady, incompressible, viscous laminar flow over a NACA 0012 foil is simulated. By applying an operator-splitting method, the 'convection' and 'diffusion' equations are solved sequentially at each time step. The convection equation is solved using the vortex particle method, and the diffusion equation using the particle strength exchange(PSE) scheme which is modified to avoid a spurious vorticity flux. The scheme is improved for variety body shape using one image layer scheme. For a validation of the present method, we illustrate the early development of the viscous flow about an impulsively started NACA 0012 foil for Reynolds number 550.