• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.204-209
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• 2001

The effects of size distribution of oil particles on the emulsion stability of mayonnaise were studied as follows; The stability of mayonnaise has concerned closely with the viscosity and the size distribution of oil particles. Mostly, if the viscosity was increased, the stability was improved, and the distribution of oil particles was uniform and the less the variation, the more the stability. 75% of oil concentration of sample showed the highest viscosity, also the size of sample was the most uniform, compared to other concentration. Mayonnaise prepared with whole egg was unstable, and the size of oil particles was double larger than the case prepared with only the yolk. Addition of xanthan gum increased, the viscosity and the stability by centrifuge so that the more stable mayonnaise could be prepared. The result of using log-normal density function by Heldmann represented that the normal size of sample adding 0.6%-soluble starch and sample N in non-adding control was increased, while those of sample adding xanthan gum and soluble starch at the same time didn't change.

• Particle and aerosol research
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• v.13 no.3
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• pp.133-139
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• 2017

In this paper, we proposed an emulsification method without using an emulsifier and investigated the effects of particle size distribution in fluids on dispersion stability. Surfactant-free oil in water emulsion was prepared with 1 % (w/w) of olive oil by using high speed agitation, high pressure and ultrasonic dispersion methods. The particle size, microscopic observation, and dispersion stability of each sample were evaluated and dispersion stability according to various dispersion methods was compared. As a result, the emulsion dispersed by the ultrasonic dispersion method showed the smallest particle size and uniform distribution of $0.07{\sim} 0.3{\mu}m$ and was the most stable in a 7 days stability evaluation. In the above experiment, four olive oil emulsions having different particle sizes were prepared using ultrasonic dispersion technology that was capable of producing stable emulsions. The dispersion stability of each samples with oil droplet sizes of (A) 0.1 to $0.5{\mu}m$, (B) 0.3 to $4{\mu}m$, (C) 1 to $10.5{\mu}m$ and (D) 2 to $120{\mu}m$, was observed for 7 days, and the relationship between the stability and performance was studied. Emulsion (A) with particle size less than $0.5{\mu}m$ displayed the dispersion stability showing below 5 % change in a 7 days stability evaluation. In the case of (B), (C), and (D) that had larger particle than $0.5{\mu}m$, the changes of dispersion stability were 10 %, 13 % and 35 % respectively. From these results, it was proved that dispersion stability of emulsion with uniform particle size of $0.5{\mu}m$ or less was confirmed to be very stable.

• Journal of Korean Society of Rural Planning
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• v.23 no.1
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• pp.97-112
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• 2017

Stability of labor market in rural areas was analyzed in this paper with categories of industrial group, employment scale, surviving period, and founder group. The stability of each classified labor market was compared with each other to figure out the stable business class and the unstable class in rural areas. The results of rural areas were compared with those of urban areas. The stability was analyzed with average and coefficient of variation (C.V.) of annual total employees' change rates. It was revealed that labor market of 'primary industry', including agriculture, is unstable. Especially, labor market of 'mid-size' and 'primary industry' businesses founded as 'incorporated company' in rural areas is vulnerable. While labor market of 'large-size' is proved to be unstable, it is confirmed that 'small-size' or 'mid-size', and 'over-ten-year survived' businesses have positive contribution to the stable labor market in rural and urban areas. The results show that the stability of labor market is different in each category of business and in each region of rural or urban area. It is expected that the results can be utilized for the regional development policies, of labor and industry part.

• Journal of the Korea Society of Computer and Information
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• v.3 no.3
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• pp.129-137
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• 1998

A position of small and medium size business is increasing in the national economic. On the other hand, there are many difficulties in the small and medium size business. The most difficult problem is the financial supply for the small and medium size business. This study is analzing the financial stability ratios of the small and medium size business in comparision with financial ratios of a large enterprise and industrial average ratio. As the result, the degree of financial stability ratio of small and medium size business is lower than industrial standard ratio. While the degree of financial stability and liquidity ratios of the small and medium size business is higher than industry average ratio. the degree of dependence of borrowing of the small and medium size business is lower. Therefore, it is necessary for nation and administration organization to supply financing for the small and medium size business.

• Fashion & Textile Research Journal
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• v.4 no.1
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• pp.86-91
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• 2002

To estimate dispersion stability of particles, suspending power and particle size were examined as functions of pHs, surfactants, electrolytes and ionic strengths using ${\alpha}-Fe_2O_3$ particle as the model of particulate soil. Suspending power and particle size were determined by UV-Vis spectrumeter and by light scattering using the polarization ratio method, respectively. The suspending power was relatively high with polyanion electrolytes and was low with neutral salts. The suspending power was biphasis, minimum pH 6~7, and the effect of surfactant on the suspending power was insignificant. Generally suspending power increased with decreasing the particle size governed aggregation of dispersed particles regardless of solution conditions. Hence the suspending power was inversely related to the particle size.

• Journal of Powder Materials
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• v.20 no.6
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• pp.479-486
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• 2013

In the present work, physicochemical treatments were introduced for de-aggregation and stable dispersion of detonation nanodiamonds (DND) in polar solvents. The DNDs in water exhibited a particle size of 138 nm and high dispersion stability without particular treatment. However, the DNDs in ethanol were severely aggregated to several micrometers in size and showed poor dispersion stability with time. To break down aggregates of DNDs and enhance the dispersion stability of them in ethanol, mechanical force and chemical surfactant were introduced as functions of zirconia ball size, kind of surfactant and amount of surfactant added. From the analyses of average particle size and Turbiscan results, it was suggested that the size of DNDs in ethanol can be reduced by only mechanical force; however, the DNDs were re-aggregated due to high surface activity. The long-term dispersion stability can be achieved by applying mechanical force to break down the aggregates of DNDs and by preventing re-aggregation of them using proper surfactant.

• Steel and Composite Structures
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• v.36 no.6
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• pp.631-642
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• 2020

This paper studies nonlinear stability behavior of a nanocrystalline silicon curved nanoshell considering strain gradient size-dependency. Nanocrystallines are composite materials with an interface phase and randomly distributed nano-size grains and pores. Imperfectness of the curved nanoshell has been defined based on an initial deflection. The formulation of nanocrystalline nanoshell has been established by thin shell theory and an analytical approach has been used in order to solve the buckling problem. For accurately describing the size effects related to nano-grains or nano-pores, their surface energies have been included. Nonlinear stability curves of the nanoshell are affected by the size of nano-grain, curvature radius and nano-pore volume fraction. It is found that increasing the nano-pore volume fraction results in lower buckling loads.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.145-148
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• 2011

The thermal behavior of lithiated Si anodes has been investigated using differential scanning calorimetry (DSC). In particular, the effect of Si particle size on the thermal stability of a fully lithiated Si electrode was investigated. For DSC measurements, a lithiated Si anode was heated in a hermetically sealed high-pressure pan with a polyvinylidene fluoride (PVDF) binder and a 1 M $LiPF_6$ solution in an ethylene carbonate (EC)-diethyl carbonate (DEC) mixture. The thermal evolution around $140^{\circ}C$ increases with lithiation and with decreasing particle size; this phenomenon is attributed to the thermal decomposition of the solid electrolyte interface (SEI) film. Exothermic peaks, following a broad peak at around $140^{\circ}C$, shift to a lower temperature with a decrease in particle size, indicating that the thermal stability of the lithiated Si electrode strongly depends on the Si particle size.

• Journal of the Korean Applied Science and Technology
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• v.32 no.3
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• pp.536-545
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• 2015

This study aimed to investigate the effect of various emulsifiers on the formation of nanoemulsions and their stability properties. MCT (medium chain triglyceride) nanoemulsions were prepared (10 wt% oil, 10 wt% emulsifiers, 20 mM bis-tris, pH 7) with emulsifier such as Tween 20 (Polyoxyethylene(20) sorbitan monolaurate), Almax 3800 (Sorbitan monooleate), soy lecithin, and SSL (sodium stearoyl lactylate) and changes in fat globule size with respect to storage period and stability properties by Turbiscan were investigated. In case of control nanoemulsion with 10 wt% Tween 20, the initial fat globule size was 89.0 nm and 113.4 nm after 28 day of storage and this large increase (ca. 24 nm) was thought to be caused by Ostwald ripening. When Tween 20 was partially replaced with Almax 3800, lecithin and SSL in nanoemulsions, their physicochemical properties (i.e., fat globule size and stability) were changed accordingly. In general, the intial fat globule size was decreased with increasing the concentration of the emulsifiers and the stability against Ostwald ripening increased. The most stable nanoemulsions against Ostwald ripening could be prepared with emulsifiers of Tween 20 and Almax 3800 or lecithin in the ratio of 6:4 (wt%), which was verified with Ostwald ripening rate (${\omega}$). In addition, the emulsion stability by Turbiscan was observed to be consistent with results of changes in fat globule size with storage period.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.3
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• pp.205-212
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• 2012

This paper proposes the fuzzy logic based variable step-size MPPT (Maximum Power Point Tracking) method for the stability at the steady state and the improvement of the transient response in the wind power system. If the change value of duty ratio is set on stability of the steady state, MPPT control traces to maximum power point slowly. And if the change value is set on improvement of the transient response, the system output oscillates at the maximum power point. By adjusting the step size with fuzzy logic, it can be improved the MPPT response speed and stability at steady state when MPPT control is performed to track the maximum power point. The effectiveness of the proposed method has been verified by simulations and experimental results.