• Journal of the Korean institute of surface engineering
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• v.32 no.2
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• pp.157-164
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• 1999

In this study the effect of nickel addition on the coating weight of mini-mill steels containing silicon has been studied. It is shown that the pure zinc accelerated growth of the alloy layers occurred by a rapid growth of the zeta phase at 0.06%Si. The addition of 0.06%Ni to a pure zinc bath was found to be very effective in reducing the coating weight and promoting preferential development of the delta phase. The coating obtained by immersion in the Zn-Ni bath shows the presence of a nickel-rich region between the zeta phase and the eta phase. It is suggested that nickel prevents the rapid growth of the zeta phase due to the formation of the Zn-Ni-Fe ternary compound, which may act as a barrier to inward diffusion of zinc or iron at the zeta-eta boundary.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2371-2385
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• 2010

What are the success factors of IT venture entrepreneur that through initial phase and enter to the growth phase ? Both the duration of jobless growth and the economic recession are worsening employment market. Entrepreneurship is be proposed to a method for creating jobs and reducing the economic gap. Research on Entrepreneurship and the support of government policy has already been operated for a long time ago. Research on growth and duration of the entrepreneur in initial phase, compared with growth phase are insignificant in quantity or quality. Therefore, this study researches essential factors about growth and duration of the entrepreneur in the initial phase through cases related them. entrepreneur of this subject are classified the hardware development group and the software development group associated with manufacturing characteristic funded existence. There is a research on evaluation factors about selection and result evaluation of selecting Entrepreneur. And this can be investigated by studying to Entrepreneur's growth and duration in initial phase. There are affecting factors about growth and duration of first step. And they are divided by internal, external, synthetic, and characteristic factors of growth phase. The result of this study is be used to develop pre-established educational program, consulting guidelines and establish support policy.

• Korean Journal of Materials Research
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• v.19 no.11
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• pp.588-595
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• 2009

The knowledge of grain growth of carbide particles is very important for manufacturing micrograined cemented carbides. In the present study, continuous and discontinuous grain growth in WC-Co and WC-VC-Co cemented carbides is investigated using the Monte Carlo computer simulation technique. The Ostwald ripening process (solution/re-precipitation) and the grain boundary migration process are assumed in the simulation as the grain growth mechanism. The effects of liquid phase fraction, grain boundary energy and implanted coarse grain are examined. At higher liquid phase content, mass transfer via solid/liquid interfaces plays a major role in grain growth. Growth rate of the implanted grain was higher than that of the matrix grains through solution/re-precipitation and coalescence with neighboring grains. The results of these simulations qualitatively agree with experimental ones and suggest that distribution of liquid phase and carbide particle/carbide grain boundary energy as well as contamination by coarse grain are important factors controlling discontinuous grain growth in WC-Co and WC-VC-Co cemented carbides. The contamination by coarse grains must by avoided in the manufacturing process of fine grain cemented carbides, especially with low Co.

• Journal of Korean Society on Water Environment
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• v.26 no.5
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• pp.834-840
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• 2010

To find out the toxin production characteristics of Korean harmful cyanobacteria, we isolated 14 cyanobacterial strains from Korean lakes and rivers and analyzed the kinds and cellular content of microcystins (MCYSTs) of cyanobacterial isolates using cultured biomass. And we measured the MCYSTs production by growth phase of two representative toxic strains, Microcystis aeruginosa (HG-015) and Anabaena planktonica (HG-012). Among seven cyanobacteral species, Microcystis wesenbergii showed the highest cellular MCYSTs content. MCYST-RR was the most dominant toxin reaching more than 85% of MCYSTs produced by isolated cyanbacterial strains. During the mass culture, Microcystis aeruginosa (HG-015) showed the highest yield and accumulation of MCYSTs in the exponential growth phase. However the cellular content of chlorophyll a and MCYSTs of Anabaena planktonica (HG-012) showed higher value in the stationary and early death phase than in the exponential growth phase. Our results suggest that control and removal of harmful cyanobacterial bloom before exponential growth phase may be effective to prevent health risk of cyanobacterial toxins in the drinking water sources.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.480.1-480.1
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• 2014

In this study, we suggest the new emitter formation applied solid phase epitaxy (SPE) growth process using rapid thermal process (RTP). Preferentially, we describe the SPE growth of intrinsic a-Si thin film through RTP heat treatment by radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD). Phase transition of intrinsic a-Si thin films were taken place under $600^{\circ}C$ for 5 min annealing condition measured by spectroscopic ellipsometer (SE) applied to effective medium approximation (EMA). We confirmed the SPE growth using high resolution transmission electron microscope (HR-TEM) analysis. Similarly, phase transition of P doped a-Si thin films were arisen $700^{\circ}C$ for 1 min, however, crystallinity is lower than intrinsic a-Si thin films. It is referable to the interference of the dopant. Based on this, we fabricated 16.7% solar cell to apply emitter layer formed SPE growth of P doped a-Si thin films using RTP. We considered that is a relative short process time compare to make the phosphorus emitter such as diffusion using furnace. Also, it is causing process simplification that can be omitted phosphorus silicate glass (PSG) removal and edge isolation process.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.677-685
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• 2018

Weaning pigs often face post-weaning challenges such as diarrhea, low feed intake, and body weight (BW) loss which affects the health and economic value of weaning pigs. Interestingly, the use of yeast cultures (YCs) as feed supplements for pigs has increased markedly in recent years. This study evaluated the effects of yeast cultures (Saccharomyces cerevisiae) on the growth performance, fecal score, and nutrient digestibility of weaning pigs. A total of 50 crossed healthy weaning pigs [(Yorkshire ${\times}$ Landrace) ${\times}$ Duroc] with an average BW of $7.46{\pm}1.60kg$ (28 day of age) were used in a 6-week experiment. The experiment was divided into 3 phases (Phase 1, 1 - 2 weeks; Phase 2, 2 - 4 weeks; Phase 3, 4 - 6 weeks). Dietary treatments were as follows: 1) CON: basal diet and 2) CON + 0.50% YC. During phase 1, the average daily gain (ADG) and average daily feed intake (ADFI) were significantly increased (p < 0.05) in the weaning pigs fed YC supplementation diets compared with the weaning pigs fed the CON diet. During phase 3 as well as overall, the gain/feed ratio (G/F) was significantly increased (p < 0.05) in the YC supplementation group compared with the pigs fed the CON diet. In conclusion, the supplementation of YCs in the diet positively affected the growth performance of weaning pigs during the first two weeks after weaning.

• Korean Membrane Journal
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• v.6 no.1
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• pp.61-69
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• 2004

Small angle light scattering (SALS) and field emission scanning electron microscope (FE-SEM) have been used to investigate the effects of alcohol on phase separation of chlorinated poly(vinyl chloride) (CPVC)/tetrahydrofuran (THF)/alcohol (9/61/30 wt%) solution during water vapor induced phase separation. A typical scattering pattern of nucleation & growth (NG) was observed for all casting solutions of CPVC/THF/alcohol. In the case of the phase separation of CPVC dope solution containing 30 wt% ethanol or n-propanol, the demixing with NG was observed to be heterogeneous. Meanwhile, the phase separation of CPVC dope solution with 30 wt% n-butanol was found to be predominantly homogeneous NG. Although the different phase separation behavior of NG was observed with types of alcohol additives, the resultant surface morphology had no remarkable differences. That is, even though the NG process by water vapor is either homogeneous or heterogeneous, this difference does not play a main role on the final surface morphology. However, it was estimated from the result of hydraulic flux that the phase separation by homogeneous NG provided the membrane geometry with lower resistance in comparison with that by heterogeneous one.

• Journal of Microbiology and Biotechnology
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• v.21 no.6
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• pp.652-658
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• 2011

The growth kinetics of Streptomyces noursei NRRL 5126 was investigated under different aeration and agitation combinations in a 5.0 l stirred tank fermenter. Poly-${\varepsilon}$-lysine biosynthesis, cell mass formation, and glycerol utilization rates were affected markedly by both aeration and agitation. An agitation speed of 300 rpm and aeration rate at 2.0 vvm supported better yields of 1,622.81 mg/l with highest specific productivity of 15 mg/l.h. Fermentation kinetics performed under different aeration and agitation conditions showed poly- ${\varepsilon}$-lysine fermentation to be a growth-associated production. A constant DO at 40% in the growth phase and 20% in the production phase increased the poly-${\varepsilon}$-lysine yield as well as cell mass to their maximum values of 1,992.35 mg/l and 20.73 g/l, respectively. The oxygen transfer rate (OTR), oxygen utilization rate (OUR), and specific oxygen uptake rates ($qO_2$) in the fermentation broth increased in the growth phase and remained unchanged in the stationary phase.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.671-674
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• 2004

BSCCO thin films have been fabricated by epitaxy growth at an ultra-low growth rate. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 655 and 820 $^{\circ}C$ and the highly condensed ozone gas pressure(PO3) in vacuum chamber was varied between $2.0{\times}10^{-6}$ and $2.3{\times}10^{-5}$ Torr. Bi 2212 phase appeared in the temperature range of 750 and 795 $^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785\;^{\circ}C$. Whereas, $PO_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$(onset) of about 90 K and $T_c$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as $CaCuO_2$ was observed in all of the obtained films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.54-54
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• 2010

This article reports a spontaneous method for controlling the growth mode from vertically arrayed ultra-slim MgZnO nanowires to nanowalls through the Zn random motion of seeds formed by surface phase separation by Mg injection near an evaporation temperature of Zn. The random motion of single crystal MgZnO seeds with relative Zn rich phase played a vital role in the growth of the MgZnO nanowalls. The seeds were networked with increasing Zn flux compared with Mg flux and closing to the evaporation temperature of Zn on phase separation layers. We achieved fabrication of MgZnO nanowalls on various non- and conducting substrates by this advanced growth method. The MgZnO nanowalls hydrogen sensor showed an improved sensing performance compared to the MgZnO nanowires grown under the similar conditions. Based on the microstructural characterizations, the growth procedure and models for the evolution of the structure transition from MgZnO nanowires to nanowalls on the Si substrates are proposed for phased growth times.