• Transactions of the Society of Information Storage Systems
• /
• v.2 no.3
• /
• pp.208-213
• /
• 2006

The present state of the design of swing arm actuators for optical disc drives is to obtain the high efficient dynamic characteristics within a very compact volume. As a necessary consequence, the need of the small form factor (SFF) storage device has been arisen as major interests in the information storage technology. In this paper, we suggest the miniaturized swing arm type actuator that has high efficient dynamic characteristics for SFF optical disk drive (ODD). For the operating mechanism, it uses a tracking electromagnetic (EM) circuit for a focusing motion together. Moreover, due to the size constraint, the thermal stability of optical head is important. Therefore, the actuator is designed to emit the heat, which is generated by optical pick-up, along the actuator body easily. Initial model is designed based on the topology optimization method considering the thermal conductivity. Then, the structural parts of the actuator are modified to maintain the high sensitivity and to have wide control bandwidth by the design of experiments method (DOE) and new concept of decreasing mass and inertia. Finally, a swing arm type actuator for SFF ODD is suggested and its dynamic characteristics are verified.

• The Korean Journal of Food And Nutrition
• /
• v.14 no.4
• /
• pp.300-304
• /
• 2001

The oxidative stability of salmon mince to which milk protein concentrate(MPC) added was investigated. Salmon mince was stored at 4$\^{C}$ for 21 days, at -18$\^{C}$ for 20 days and at -18$\^{C}$ for 20 days after cooking in an electric omen. At each storage point, peroxide values(POV) were determined. Salmon mince with 4% MPC increased greater oxidative stability than control (without MPC). Sensory evaluation for measuring the oxidative stability of salmon mince was accomplished. Sensory scares of salmon mince with 4% MPC were higher than those of control. The results indicate that MPC could be useful for oxidative stability, as stabilizing protein ingredient of salmon mince.

• Journal of Microbiology and Biotechnology
• /
• v.15 no.1
• /
• pp.29-34
• /
• 2005

W/O/W (water-in-oil-in-water) type multiple emulsion was applied to improve the storage stability of an antagonistic microorganism, Burkholderia gladioli. Encapsulation of microorganism into a W/O/W emulsion was conducted by using a two-step emulsification method. W/O/W emulsion was prepared by the incorporation of B. gladioli into rapeseed oil and the addition of polyglycerin polyriconolate (PGPR) and castor oil polyoxyethylene (COG 25) as the primary and secondary emulsifier, respectively. Microcrystalline cellulose was used as an emulsion stabilizer. To evaluate the usefulness of W/O/W emulsion formulation as a microbial pesticide for controlling the bacterial wilt pathogen (Ralstonia solanacearum), the storage stability and antagonistic activity of emulsion formulation were tested in vitro. The storage stability test revealed that the viability of formulated cells in emulsion was higher than that of unformulated cells in culture broth. At $4^{\circ}C$, the viabilities of formulated cells and unformulated cells at the end of 20 weeks decreased to about 2 and 5 log cycles, respectively. At $37^{\circ}C$, the viability of formulated cells decreased to only 2 log cycles at the end of storage. On the other hand, the viable cells in culture broth were not detected after 13 weeks. In activity test, formulated cells in emulsion were more effective in inhibiting the growth of pathogen than unformulated cells in culture broth. Unformulated cells completely lost their antagonistic activity during storage under similar conditions. The W/O/W multiple emulsion formulation was shown to be useful as the novel liquid formulation for biological control.

• Applied Biological Chemistry
• /
• v.35 no.4
• /
• pp.260-264
• /
• 1992

In present paper, we investigated the quality stability of sardine burgers during storage at $-20{\pm}2^{\circ}C$. During frozen storage of sardine burger, the PH were decreased, while volatile basic nitrogen contents were increased. The results of changes in peroxide values, thiobarbituric acid values, fatty acid compositions and color values during frozen storage showed that lipid oxidation and discolorization of antioxidant treated sardine burger and vacuum packed sardine burger could be effectively retarded. The changes in the taste compounds such as free amino acid, nucleotide and their related compounds, total creatinine, betaine and trimethylamine oxide, total amino acids and texture profile analysis of vacuum packed sardine burger were negligible during frozen storage. From the results of sensory evaluation and chemical experiments, the vacuum packed sardine burger could be preserved in good quality during frozen storage of 90 days.

• Food Science and Preservation
• /
• v.16 no.4
• /
• pp.590-593
• /
• 2009

The effect of gamma irradiation on the storage stability of Undaria pinnatifida was investigated. A three-log reduction in total aerobic bacteria in U. pinnatifida samples was obtained by irradiation with 3 kGy. During storage for 2 weeks, the viable counts of microorganisms in non-irradiated U. pinnatifida increased to 6 log CFU/g. However, irradiation of U. pinnatifida by 5 kGy eliminated microorganisms. The Hunter $L^{\ast}-value$ of U. pinnatifida was slightly increased after 5 kGy of irradiation. The hardness properties of U. pinnatifida decreased during storage, but were not changed by irradiation with up to 3 kGy. These results indicate that low-dose irradiation (3 kGy) could be effective for improvement of the storage stability of U. pinnatifida.

• Korean Journal of Food Science and Technology
• /
• v.20 no.4
• /
• pp.569-575
• /
• 1988

Storage stabilities of ramyons fried in palm oil and beef tallow with added antioxidants and their synergists were investigated by comparing the changes in physicochemical parameters and n-hexanal concentrations of oils extracted from ramyons during storage. Ramyons fried in palm oil and beef tallow with added ${\delta}-tocopherol$ $({\delta}-toc)$ showed an enhanced storage stabilities when compared to those fried in the oils with ${\alpha}-tocopherol$ $({\alpha}-toc)$. Ascorbyl palmitate was found to be a better synergist than citric acid for the antioxidant activity of both ${\delta}-toc\;and\;{\alpha}-toc$. Phenolic antioxidants gave a better storage stability than tocopherol when ramyon was fried in beef tallow, while a mixture of BHA and BHT gave an inferior storage stability than${\alpha}-toc$ when ramyon was fried in palm oil. The effectiveness of the antioxidants tested on storage stability of stored ramyon had a close relationship to the n-hexanal concentration. On the other hand, the paramenters such as peroxide value, carbonly value, and conjugated diene concentration showed inconsistency during the course of the storage experiment.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.05a
• /
• pp.314-317
• /
• 2002

The sloshing phenomenon sometimes happens to be occurred in the liquid storage tank due to the unexpected and/or inevitable vibrating conditions and may result in severe effects on the structural stability. This study deals with the development of experimental techniques for the evaluation of sloshing behavior in the liquid storage tank and for the identification of natural frequencies and mode shapes by varying with various vibrating conditions. In addition, suitable method is suggested to minimize the sloshing effect on the liquid storage tank and its validity is experimentally investigate d.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2009.10a
• /
• pp.258-263
• /
• 2009

This paper describes an analysis of the stability and performance of a large-capacity flywheel energy storage system (FESS) supported by active magnetic bearings. We designed and manufactured the system that can store up to 5kWh of usable energy at the maximum speed of 18,000 rpm. In order to analyze the stability of the systems accurately, we derived a rigid body rotor model, flexible rotor model using finite-element method, and a reduced-order model using modal truncation. The rotor model is combined with those of active magnetic bearings, amplifiers, and position sensors, resulting in a system simulation model. This simulation model is validated against experimental measurements. The stability of the system is checked from the pole locations of the closed-loop transfer functions. We also investigated the sensitivity function to quantify the robustness of the systems to the disturbances such as mass imbalance and sensor noises.

• Korean Journal of Food Science and Technology
• /
• v.20 no.6
• /
• pp.868-872
• /
• 1988

The oxidation behaviour of Pinenut(Pinus Koraiensis S & Z) oil during storage were studied. And the oxidative stability of different oil samples by refining stage were also measured. The oil in whole pinenut or mashed pinenut was very stable during the storage at $35^{\circ}C$ for 10 weeks however, the oxidation rate was enhanced when pinenut oil was extracted and isolated from nut cake. On the other hand, crude oil was most stable and the highly purified pinenut oil was least stable, with other samples being intermediate in stability. The changes of fatty acid composition of various pinenut oil samples during storage were also discussed.

• YAKHAK HOEJI
• /
• v.43 no.6
• /
• pp.793-797
• /
• 1999

Salmonella typhi Ty21a is an attenuated strain of S. typhimurium and used for oral typhoid vaccine. In an attempt to increase the stability of Ty21a manufacturing typhoid vaccine, we studied about the stability of freeze-dried Th21a including additives at various temperature conditions. In order to investigate the freeze-drying rate of Ty21a according to various absorbance, we lyophilized Ty21a by using 8% sucrose as a stabilizer. The optimal freeze-drying rate of Ty21a was appeared when OD (optical density) value of the growth was between 2.5 and 3.0. To investigate the stability of Ty21a at various temperature, the viability was measured after storaging the freeze-dried Ty21a at the room temperature, cold and freezing condition for 1 week. The viability of Ty21a in cold and freezing storage condition was 5 times more stable than in room temperature. To search the most stable additives for the freeze-dried Ty21a, the viability of Ty21a including additives at the various storage condition was estimated. Mannitol and loctose were the most stable additives. Theses results suggest that the OD value of Ty21a growth, low temperature, mannitol and lactose are important factors for the optimal freeze-drying rate, the stable storage and the most stable additives, respectively.