• Korean Journal of Human Ecology
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• v.14 no.2
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• pp.321-330
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• 2005

The antimicrobial activity of PHB/chitosan films and the quality of white bread packaged with the films were investigated. Chitosan film showed the highest antimicrobial activity and PHB(L) film also showed high antimicrobial activity against Fusarium solani KCTC 6636 and Penicillium citreonigrum KCTC 6927. White bread packaged with chitosan film had good moisture retention. $L^*\;and\;b^*$ of white bread increased but $a^*$ did little change during storage regardless of the film kind. The TBA values of white bread packaged with chitosan or PHB(L) film slowly increased during storage. The springiness of white bread packaged with PHB(M), PHB(L) and chitosan film was high. The colony forming units of microorganisms for white bread packaged with chitosan film were low during storage. Therefore, PHB(M), PHB(L) and chitosan films were superior to PHB(H) and PHB films as package material for white bread.

• Journal of the Korean Dietetic Association
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• v.15 no.1
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• pp.69-76
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• 2009

To determine the salinity of packaged Kimchi, bulk Kimchi and other common foods, we collected samples of foods from the Gyeonggi province area in October 2006 and determined the salinity levels in one serving portion. The average salinity of all foods was 0.226${\pm}$0.212%. The average salinity of all Kimchi samples was 0.401${\pm}$0.260. The average salinities of soups, stews, protein containing side dishes, vegetable side dishes and drinks were 0.153${\pm}$0.085%, 0.691${\pm}$0.213%, 0.151${\pm}$0.102%, 0.209${\pm}$0.121% and 0.080${\pm}$0.016%, respectively. The average salt intake of one serving of Kimchi was 0.125${\pm}$0.041 g, while the average salt intakes of one serving of the soups, stews, protein containing side dishes, vegetable side dishes and drinks were 0.306${\pm}$0.170 g, 1.382${\pm}$0.426 g, 0.094${\pm}$0.061 g, 0.146${\pm}$0.089 g, and 0.159${\pm}$0.152 g, respectively. The salinity of packaged Kimchi was significantly higher than the salinity of the bulk Kimchi (p < 0.01). In addition, the salinity of the liquid and solid stem portions of the packaged Kimchi was significantly higher than the salinity of the same sized portions of the bulk Kimehi (p<0.01). Furthermore, the salinity in the liquid and solid stern portions of the packaged mustard leaf Kimchi were significantly higher than the salinities of other types of Kimchi (p < 0.0001). The salinity of all Kimchi is higher than that of soup, protein containing side dishes, vegetable side dishes or drinks, but the salt content of one serving of Kimchi is lower than those of the soups or stews or vegetable side dishes or drinks (because one serving size of Kimchi is usually smaller than that of the other foods).

• Applied Biological Chemistry
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• v.48 no.2
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• pp.120-127
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• 2005

Electron beam irradiation was applied to examine the microbial growth and qualities of vacuum-packaged chicken breasts. Chicken breast samples were irradiated at dose of 2, 4, 8, 12, and 16 kGy, respectively. After irradiation, chicken breast samples were individually vacuum-packaged and stored at $4^{\circ}C$. Microbiological change of irradiated vacuum-packaged chicken breasts showed that populations of total bacteria, yeast and mold, total coliform, and salmonella spp. in chicken breasts were significantly reduced with increasing irradiation dose. The pH values of vacuum-packaged chicken breasts were not significantly changed among treatments. Lipid oxidation measurements showed that TBARS values of vacuum-packaged chicken breasts increased with increase of irradiation dose, and gradually increased during storage. Color measurements showed that irradiation reduced Hunter a value of vacuum-packaged chicken breasts with increasing irradiation dose. However, Hunter L and b values of vacuum-packaged chicken breasts were not significantly altered among treatments. Sensory quality results of vacuum-packaged chicken breasts showed that there were no significant changes among the samples irradiated. These results indicate that irradiation can be used to improve the microbial safety and qualities of poultry products.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.62-67
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• 1994

Quality change of Kimchi packaged with Ny/PE, Ny/CPP (PPtray+Ny/CPP cover), Cryovac BK-1, BK-4, and PET/Al/PE film was observed during storage at $5^{\circ}C$ (97%RH) and $20^{\circ}C$ (76%RH). To evaluate quality change of Kimchi, gas composition of package, pH, acidity, color, growth of lactic acid bacteria, and sensory score were measured periodically. Regarding to gas composition of package, Kimchi packaged with PET/Al/PE showed higher oxygen concentration at the beginning of storage than the others; carbon dioxide concentration was almost 100% at the end of storage. Carbon dioxide concentration of Kimchi packaged with Cryovac BK-1 and BK-4 which has higher gas permeability than the others, was increased to a maximum and then decreased due to permeation of gas during storage; oxygen concentration was increased. Unlike Kimchi packaged with Ny/PE, Ny/CPP, and PET/Al/PE, package swelling was not observed in Kimchi packaged with Cryovac BK-1 and BK-4 during storage. Although pH change was not significant depending on the packaging material, Kimchi packaged with Cryovac BK-1 and BK-4 showed lower pH value and higher acidity than those of the others. Color change of Kimchi was different depending on the packaging material during storage. Difference of the growth of lactic acid bacteria and sensory evaluation were not significant among Kimchi packaged with different packaging material during storage at either temperature. In conclusion, the effect of packaging materials on the quality change of Kimchi was not significant; however, to prevent from swelling of packaged Kimchi which is one of the most serious problem during storage and distribution, might be avoided by using relatively high $CO_2$ permeable film than high gas barrier film.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.944-950
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• 1996

The purpose of our study is to investigate the changes of physico-chemical properties according to packaging methods(vacuum packaged with polyamide/polyethylene, air packaged with polyvynyl-chloride) and illumination on the properties of Hanwoo beef. pH value in vacuum packaged beef tended to be decreased, but pH value in air packaged beef tended to be increased during storage for 21 days, irrespective of illumination. Contents of volatile basic nitrogen(VBN) and thiobarbituric acid(TBA) values were increased, regardless of packaging methods. However, vacuum packaged beef showed lower VBN, TBA values than those of air packaged beef. Red color(CIE a value) was also decreased. Regardless of packaging method, saturated fatty acids(SFAs) were increased, but unsaturated fatty acids(UFAs) were relatively decreased. And in the ratio of the UFA/SFA, vacuum packaged beef had lower UFA/SFA ratio than that of air packaged beef. In this study, the effect of illumination did not change on physico-chemical properties in Hanwoo beef. In conclusion, the results indicate that the vacuum packaging treatment was more important to prolong the shelf-life of Hanwoo beef than air packaging method.

• Journal of Life Science
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• v.19 no.4
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• pp.486-491
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• 2009

This study was conducted to investigate microbial distribution in the processing steps and to estimate quality index and shelf life of packaged Tofu (soybean curd). Sanitation and safety of Tofu were analysed in aspects of total viable counts (TVCs) and coliforms. Organoleptic deterioration was observed from some packaged Tofu when their TVCs were over $10^6\;CFU/g$. The controlled simply packaged Tofu and sterilized Tofu with TVCs of under $10^5\;CFU/g$ were 32.0% and 86.9% of the total samples, respectively. Also, the controlled simply packaged Tofu and sterilized Tofu with negative coliforms were 12.0% and 83.7% of the total samples, respectively. TVCs and coliforms increased in some processing steps, which include washing and soaking of raw soybeans, and formation and 1st cooling of packaged Tofu. Increases of TVCs and coliforms in the washing and soaking step were due to contamination from the soaking tank and airborne bacteria, whereas increases of TVCs and coliforms in the grinding step were due to contaminations from the grinder, line and reserving tank. TVCs and coliforms increased in the formation and 1st cooling step of packaged Tofu due to contaminations from filter wools, trays, employee's hands, cooling water, formed products and filter wools.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.361-368
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• 2011

This study aims to examine the consumer preference for packaged bean curd that takes a growing public interest. Specifically, this study tried to examine which is more important - the place of origin of the raw bean or the environmental-friendliness of the raw bean. Surveys were conducted to obtain information, such as the consumer evaluation for food safety on imported food products from China and the consumer perception of Chinese organic food products, Using the binary probit model, the relationship between consumer's choice of packaged bean curd and potentially important factors that can affect the consumer's choice was analyzed. A summary of this research and some policy implications follow. The results of this study can be used as the basic guideline as to how to extend the safety of imported food products, in general, and how to further develop the packaged bean curd industry in Korea, in particular.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.632-639
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• 2014

Mechanical stress and the vacuum level are the two main factors dominating the quality factor of a resonator operated in the vacuum range 1 mTorr to 10 Torr. This means that if the quality factor of a resonator is very insensitive to the mechanical stress in the vacuum range, it is sensitive to mainly the ambient vacuum level. In this paper, a wafer-level packaged MEMS resonator with a highly vacuum-sensitive quality factor is presented. The proposed device is characterized by a package with out-of-plane symmetry and a suspending structure with only a single anchor. Out-of-plane symmetry helps prevent deformation of the packaged device due to thermal mismatch, and a single-clamped structure facilitates constraint-free displacement. As a result, the proposed device is very insensitive to mechanical stress and is sensitive to mainly the ambient vacuum level. The average quality factors of the devices packaged under pressures of 50, 100, and 200 mTorr were 4987, 3415, and 2127, respectively. The results demonstrated the high controllability of the quality factor by vacuum adjustment. The mechanical robustness of the quality factor was confirmed by comparing the quality factors before and after high-temperature storage. Furthermore, through more than 50 days of monitoring, the stability of the quality factor was also certified.

• Transactions of the Korean hydrogen and new energy society
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• v.31 no.1
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• pp.73-81
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• 2020

For the fault tree analysis (FTA) analysis of the packaged hydrogen filling station, the composition of the charging station was analyzed and the fault tree (FT) diagram was prepared. FT diagrams were created by dividing the causes of events into external factors and internal factors with the hydrogen event as the top event. The external factors include the effects of major disasters caused by natural disasters and external factors as OR gates. Internal factors are divided into tube tailer, compressor & storage tank, and dispenser, which are composed of mistakes in operation process and causes of accidents caused by parts leakage. In this study, the purpose was to improve the hydrogen station. The subjects of this study were domestic packaged hydrogen stations and FTA study was conducted based on the previous studies, failure mode & effect analysis (FMEA) and hazard & operability study (HAZOP). Top event as a hydrogen leaking event and constructed the flow of events based on the previous study. Refer to "Off shore and onshore reliability data 6th edition", "European Industry Reliability Data Bank", technique for human error rate prediction (THERP) for reliability data. We hope that this study will help to improve the safety and activation of the hydrogen station.

• Journal of Biosystems Engineering
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• v.34 no.6
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• pp.454-461
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• 2009

The purpose of this study is to analyze the RFID recognition performance by level of water. A 13.56 MHz RFID management system for packaged liquid food logistics is consisted of antenna, reader, passive type tags, and embedded controller. The tests were conducted at different level of water, distances between tag and antenna, and position of attached tags. To analyze the RFID recognition performance, maximum recognition distances for a container and recognition rates for a logistics made of 27 containers were measured and analyzed. The maximum recognition distance for a container was different depending on position of attached tags, and attached tag at upside position showed a good performance. But, the recognition rate of 27 containers showed a good ability for attached tags at front side position, 30~35 cm distance to antenna, and water level 1. Therefore, to manage packaged liquid food logistics using RFID system, position of attached tag, distances between tag and antenna, and level of water should be considered.