• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.786-793
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• 1999

To investigate the effects of medicinal plants on the shelf life of kakdugi, various kakdugies, added with hot water extract from 62 natural plants, were fermented at 20oC for 15 days. In case of control without the addition, the shelf life required to reach the acidity of 1%(as lactic acid) was 7 days. Morethan two fold extension of shelf life was observed with twenty seven extracts, of which six extracts maintained the hardness of kakdugi higher than that of control over the entire fermentation time. And the number of lactic acid bacteria in above kakdugies was not remarkably different from that of control, and the color(a value) of the liquid of kakdugi, added with Chaenomeles lagenaria, Moringa oleifera, Peaonia lactiflora or Citrus tangerina extract, was similar to that of control. In sensory test, the extracts from the above plants except Moringa oleifera were found to be acceptable. It is suggested that the addition of above three extracts may lead to extension of shelf life of kakdugi, based on the acidity, hardness, color and sensory test.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.1
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• pp.124-132
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• 2018

This paper presents a shelf life assessment for K-1 military gas masks in the Republic of Korea using test data of Chemical Materiels Stockpile Reliability Program(CSRP). For the shelf life assessment, over 2,500 samples between 2006 and 2015 were collected from field tests and analyzed to estimate a probability of proper and improper functionality using Bayesian estimation. For this, three stages were considered; a pre-processing, a processing and an assessment. In the pre-processing, major components which directly influence the shelf life of the mask were statistically analyzed and selected by applying principal component analysis from all test components. In the processing, with the major components chosen in the previous stage, both proper and improper probability of gas masks were computed by applying Bayesian estimation. In the assessment, the probability model of the mask shelf life was analyzed with respect to storage periods between 0 and 29 years resulting in between 66.1 % and 100 % performances in accuracy, sensitivity, positive predictive value, and negative predictive value.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.8
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• pp.1-11
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• 2008

The purpose of this study is to present the design guideline for an effective application of light shelf in office building. For this, the computer simulation using Daylighting System of 3Ds Studio Max was performed, and the optimal values related to design factors such as a depth, a surface reflectance and a installation angle of light shelf were obtained. Then daylighting performance of light shelf using the optimal values was analyzed, and the simulation results show that the installation of the optimal light shelf can improve a indoor lighting environment in office building.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1284-1290
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• 2007

This study was conducted to investigate the antibacterial activity and shelf-life extension effect of iceberg lettuce packed in BN/PE film. The BN/PE film has a strong microbial suppression effect on pathogenic bacteria such as Escherichia coli, Salmonella enteritidis, and S. typhimurium. The number of psychrophiles and mesophiles during 5 days of cold storage of fresh-cut iceberg lettuce at $10^{\circ}C$ packaged in BN/PE film was strictly suppressed in comparison with other tested films (OPP, PE, and PET film). When fresh processed iceberg lettuce was processed and stored under the current conditions, the shelf-life of the product was longer than 5 days in the BN/PE film package, whereas the shelf-life when using the other films tested, PE, OPP and PET, was no longer than 3-4 days. The decay rates of the iceberg lettuce packed in the BN/PE film was maintained at $29.8{\pm}2.1%$ on the 5th day of preservation. The samples packed in BN/PE film maintained an excellent visual quality during the 3 days of storage without significant differences in comparison with the initial visual quality. No browning was observed in the samples packed in BN/PE film for up to 3 days. The texture of shredded iceberg lettuce packaged in BN/PE film remained unchanged up to 3 days, and then a moderate decrease in texture was observed after 4 days of storage. In addition, the overall acceptability of fresh-cut iceberg lettuce packaged in BN/PE film did not change for up to 3 days, whereas the samples packaged in the other films were inedible by 3 days of storage. In conclusion, the shelf-life of fresh-cut iceberg lettuce packaged in the BN/PE film was extended to more than 5 days at $10^{\circ}C$, whereas that in the other films was 2 days at $10^{\circ}C$. Therefore, the shelf-life extension effect of the fresh-cut iceberg lettuce in BN/PE film packaging was very effective compared with the other films tested.

• Journal of Biosystems Engineering
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• v.40 no.4
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• pp.345-358
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• 2015

Southeast Asia, a typical tropical region, plays an important role in exporting a variety of fruits worldwide. The market for fresh fruits has been growing consistently, and this is a chance for Southeast Asian countries to increase their national income. However, export of tropical fruits has limitations such as a short shelf life and difficulty in maintaining the quality because of tropical climate conditions and undeveloped postharvest technologies in Southeast Asia. An important objective for developing postharvest technologies is to extend the shelf life of fresh fruits without deterioration in fruit quality. Therefore, it is essential to determine factors that affect the shelf life of fruits. The shelf life of tropical fruits is significantly dependent on the inherent properties of the fruits, extrinsic conditions, postharvest treatment, and microbial contamination. Recently, Southeast Asian countries have supported agricultural research groups for developing new postharvest technologies and minimizing postharvest losses and maintaining export fruit quality so that the total sales of tropical fruit farms can increase. This review introduces how the primary factors for extending the shelf life of tropical fruits can be determined and discusses the development of postharvest technologies for tropical fruits in Southeast Asian countries.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.5
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• pp.343-353
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• 2018

Ocean tides in Antarctica are not well constrained mostly due to the lack of tidal observations. Especially, tides underneath and around ice shelves are uncertain. InSAR (Interferometric Synthetic Aperture Radar) data has been used to observe ice shelf movements primarily caused by ocean tides. Here, we demonstrate that it is possible to estimate tidal constituents underneath the Sulzberger ice shelf, West Antarctica, solely using ERS-1/2 tandem mission DInSAR (differential InSAR) observations. In addition, the tidal constituents can be estimated in a high-resolution (~200 m) grid which is beyond any tidal model resolution. We assume that InSAR observed ocean tidal heights can be derived after correcting the InSAR data for the effect of atmospheric loading using the inverse barometric effect, solid earth tides, and ocean tide loading. The ERS (European Remote Sensing) tandem orbit configuration of a 1-day separation between SAR data takes diminishes the sensitivity to major tidal constituents including $K_1$ and $S_2$. Here, the dominant tidal constituent $O_1$ is estimated using 8 differential interferograms underneath the Sulzberger ice shelf. The resulting tidal constituent is compared with a contemporary regional tide model (CATS2008a) and a global tide model (TPXO7.1). The InSAR estimated tidal amplitude agrees well with both models with RMS (root-mean-square) differences of < 2.2 cm and the phase estimate corroborating both tide models to within $8^{\circ}$. We conclude that fine spatial scale (~200 m) Antarctic ice shelf ocean tide determination is feasible for dominant constituents using C-band ERS-1/2 tandem mission InSAR.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.937-943
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• 1996

The biggest Problem of low-salted Jeot-gal is the reduction of its shelf-life. Chitosan, glucono $\delta-lactone, $ and sykeeper were added to extend the shelf-life of low-salted Myungran-jeot, and various chemical and microbiological analyses were carried out during fermentation at $10^{\circ}C.$ Sykeeper inhibited the increase in pH, and production of lactic acid, VBN, TMA, TBA, and the microbial growth, whereas enhanced the production of amino-N. But, chitosan and glucono $\delta-lactone$ had no significant difference from the control. The estimated shelf-life periods of low-salted Myngran-jeot fermented at $10^{\circ}C$ for control, chitosan, glucono $\delta-lactone, $ and sykeeper were about 14, 12, 16, and 19 days, respectively.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.940-946
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• 1996

One of the biggest Problems in making jeotkal is the reduction of its shelf-life when lowering the salt content from 20-30% to below 10%. Therefore, in order to extend the shelf-life of the low-salted jeotkal, prior to setting the minimum allowance value of sulfiting agents as food additives for fermented fish products, the preservative effects of sulfite salts on the low-salted myungranjeot (soused roe of Alaska pollack) were studied through various chemical and microbial analyses. The pHs of the low-salted Myungranjeot treated with bisulfite and metasulfite salts rapidly decreased in the biginning of fermentation, while the lactic acid contents increased constantly. Sodium bisulfite and metasulfite enhanced the production of $NH_2-N$ after 10 day-fermentation, whereas they inhibited the production of VBN, TMA and TBA, and the growth of microorganisms including fungi during fermentation. The estimated shelf-lives of low-salted myungranjeot treated with control, sodium sulfate, sodium bisulfite, and sodium metasulfite on the basis of VBN 50 mg% were about 16, 14, 20 and 24 days, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.443-456
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• 1992

For a linear double shelf bottom topography as in the Yellow Sea, the dispersion relation of coastally trapped waves is derived for the general case Including high-frequency and short waves and for the case of low-frequency and long waves. With linear bottom topography, the governing equation is Bessel's equation for the latter case but Hummer's equation for the former case. Hypergeometric Functions, which are the solutions of Hummer's equation, are derived and converted to various special functions for the limiting cases. On a double shelf topography, the divergence effects of horizontal flow are important for the wave dynamics, irrespective of cross-shelf dimensions, while on a single shelf they are usually neglected when the cross-shelf dimension is much smaller than the Rossby deformation radius. The divergence effect allows the existence of Kelvin wave and reduces the phase speeds of continental shelf waves. Finally, the frictionless eigenfunctions are proved to be orthogonal.

• The Korean Journal of Quaternary Research
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• v.4 no.1
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• pp.15-26
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• 1990

Narrow (10-20 km wide) and steep (0.3-$2.4^{\circ}$) continental shelf off the eastern coast of Korea is covered with terrigenous clastic sediments reflecting the Holocene fluctuation of sea level. Surface sediments on the inner shelf consist of muddy sand and sandy mud with some gravels near the coast. However, sand or muddy sand, shell fragments and well rounded gravels occur near the edge of continental shelf at the depth of about 130-l50m. The coarse sediments near the shelf edge seem to be the relict or palimpsest sediments deposited under the nearshore environment during the low-stand or sea level due to so-called the Wisconsinan glaciation. Distribution of recent sediments near the coast and the inner shelf may reflect the affect of waves and currents precluding the deposition of fine sediment near the coast and on the shallow portion of shelf. Eastern Korean Warm Current also nay have played an important role to the transport and distribution of fine sediments from the south.