• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.6
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• pp.130-137
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• 2003

Because of falling-off in power quality by harmonics, obstacles like lowering of capability, noise, vibration of power facilities and so on are occurred. Also generation of harmonics is inevitable and the point at harmonics is seriously gathering strength because energy saving installation using semiconductor circuit as countermeasures to enhance energy efficiency will be broadly spread and the use of energy conversion equipment like motor speed control contrivance, energy keeping installation and so on will increase, in the future. In order to eliminate harmonics obstacle, precision measurement and analysis on voltage, current, power factor, the each ingredient of harmonic order, the percentage of total harmonic distortion, and so forth are needed. In this paper, we developed low-cost measurement system to measure and analyze power quality connected with harmonics and verified it's performance by measuring and analyzing power quality in the three-phase and four-wire system.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.507-513
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• 2004

Microbiological safety investigation of 36 commercial salt-fermented shrimps revealed presence of coliform and Gram(+) cocci, whereas pathogenic bacteria such as Escherichia coli O26, Salmonella, Shigella, Staphylococcus aureus, Vibrio parahaemolyticus, and V. cholerae were not detected. When pathogenic bacteria were inoculated into 9, 18, and 27% salted shrimps, Salmonella so., E. coli O26, and S. aureus were not detected up to 13, 80, and 90 days of fermentation at $20^{\circ}C$, respectively, whereas up to 15 day in commercial salt-fermented shrimps.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.15 no.1
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• pp.17-23
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• 2009

Current status on consumption and packaging of sweet persimmons in USA was surveyed by visiting the market, and three sea shipments were conducted as model export trial from Korean to USA with measurement in ship container temperature and fruit quality. Strategy to promote the export of Korean persimmons was derived. There have been gradual decrease in the price of persimmons due to their increases production, but there seems potential growth in consumption of the fruits from Asian, Hispanic and American people. Compared to the fruits from other countries, Korean persimmons are desired to have higher soluble solid content with stronger red color, but too large sizes are not favored in American market. There has often been temperature fluctuation in shipment container during the sea transport to USA, resulting in surface blackening, skin black spotting and flesh softening. Plastic bag packages with inappropriate unitizing crimping were found to sometimes build up unproper modified atmosphere (high $O_2$ and low $CO_2$) giving high rate of physiological injury.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.75-80
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• 1987

We investigated physico-chemical properties of hard wheat flours for frozen yeast-raised breadmaking and freezing stability of frozen dough prepared by the straight no-time method. The general Composition of wheat flours were : moisture ; 14.0%, ash ; 0.48%. protein ; 13.15%, and dry gluten ; 13.43%. In farinograph data, development time and water absorption were 5.5 mimutes and 62 %, respectively. Amylograph maximum viscosity was 500 BU. Resistance to extention increased with the time and their extensibility decreased in the extensigraph data. From these results obtained from these physico-chemical properties, it was confirmed that the used wheat flours were most suitable for bread-baking. Considering effect of gassing power on cold storage period and fermentation time, it was effective that dough temperature should be adjusted to $20^{\circ}C$ in order to decrease freezing injury and maintain freezing stability.

• Horticultural Science & Technology
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• v.17 no.2
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• pp.118-122
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• 1999

Quality changes of fruit vegetables were investigated during simulated export and marketing to find out the optimum shipping temperature. Fruit vegetables were loaded into a small refrigerated-container and kept for four days at various temperatures, and fruit quality was assayed immediately after harvest, 4 days after storage and 4 days after marketing at ambient temperature. In 'Back Seong Ilho' cucumber fruits, fresh weight loss was further reduced at $13^{\circ}C$ and $11^{\circ}C$ than at $15^{\circ}C$ and room temperature. Soluble solid contents remained at relatively lower levels when cucumbers were stored at $13^{\circ}C$ and $11^{\circ}C$. In 'Chun Ryang' eggplant fruits, fresh weight loss was greatly increased at all the temperatures (room, $12^{\circ}C,\;9^{\circ}C,\;and\;6^{\circ}C$). However, flesh browning, a primary quality factor of eggplant fruit, was most effectively inhibited at $9^{\circ}C$, whereas chilling injury occurred in fruit flesh at $6^{\circ}C$. Water loss of 'Eals Seinu' melon fruits was most inhibited and soluble solid contents at harvest were maintained for the longest period at $4^{\circ}C$. In 'Pe Pe' cherry tomatoes, storage at $10^{\circ}C$ and $7^{\circ}C$ seemed to more effectively inhibit metabolic changes and the incidence of cracking, the severest disorder than room temperature. But the fruits stored at $10^{\circ}C$ contained higher level of soluble solids than those at $7^{\circ}C$. The overall results suggest that the optimum shipping temperature range is 11 to $13^{\circ}C$ for cucumbers, around $9^{\circ}C$ for eggplant fruit, $4^{\circ}C$ for melons, and $10^{\circ}C$ for cherry tomatoes.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.126-127
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• 2003

원예산물의 밀도나 비중은 내부성분, 숙도, 내부붕괴(internal breakdown)와 같은 생리장해에 큰 영향을 받기 때문에, 밀도를 측정함으로써 내부품질에 대한 간접적인 판정이 가능하다고 보고되고 있다. 이 연구는 수박의 밀도와 당도와의 상관관계를 구명하고자 수행하였으며, 이를 위해 밀도의 실시간 계측시스템을 개발하였다. 현재 농산물의 밀도를 어느 정도 측정 정밀도를 유지하면서도 신속하게 측정할 수 있는 방법은 부력법(platform scale method)이다. 이 방법은 일정 크기의 용기에 물을 가득 채운 후 대상물을 담가 배제된 물의 무게를 측정하여 밀도를 환산한다. 그러나 매번 측정할 때마다 물을 보충하고, 물을 계량해야하는 등 전처리과정이 복잡하고, 1회 측정하는데 3~5분 정도가 소요되는 단점이 있고, 또한 인력 측정시 반복간 오차가 클 것으로 예상된다. 따라서 이 연구에서는 이 같은 계측상의 번거로움을 해소하고 동시에 신속하고 반복간 측정정밀도를 높일 수 있도록 수박 밀도 실시간 계측시스템을 설계 제작하였다. 시스템은 투명아크릴 수조($\Phi$400$\times$500), 로드셀, 프레임, 채반, 전기모터, 제어장치 및 컴퓨터로 구성하였다. 밀도 계측은 인장형 로드셀(CAS SB-20L, Max. 20kg)을 사용하여 대기중에서와 수박을 완전히 물에 잠기도록 한 후 무게를 각각 측정하여 밀도를 환산하였다. 밀도 계측시스템에 이용한 AD변환기의 분해능은 12bit이고, 수박의 무게 측정범위를 4~10kg로 가정할 때 20kg 로드셀의 1 digit(1bit)로 발생되는 오차는 0.09~0.24%FS 이었고, 따라서 이 시스템의 밀도 해상도는 0.001g/㎤이하였다. 시스템 평가를 위해 탄력이 좋은 고무풍선에 수박 크기 정도로 물을 채워 고정채반에 넣고 밀도를 측정한 결과 1.002g/㎤을 나타냈다. 즉 물의 이론밀도인 1g/㎤에 근접한 값을 보여 정확한 밀도 계측이 가능한 것으로 판단되었다. 또한 밀도 계측시스템의 측정 반복간 정밀도를 파악하기 위해 수박 6개를 임으로 선정하여 3반복 측정 시험한 결과, 측정표준편차가 0.001~0.004g/㎤로 해상도보다는 다소 높았으나 대체로 양호한 결과를 나타냈다. 수박 35개를 이용하여 개발 계측시스템과 사람이 직접 부력법으로 밀도를 측정 비교한 결과, 계측시스템에 의해 측정된 수박 밀도가 사람이 측정했을 때 보다 낮게 측정되었다. 수박의 외관인자(무게, 길이, 직경, 체적), 밀도와 당도의 상관관계 구명시험을 위해 원예연구소 시험포장에서 재배된 삼복꿀수박 총 74개를 공시재료로 하였고, 시험은 출수일별로 10~14개씩 수확하여 외관인자, 밀도, 당도를 각각 측정하고, 이들 인자들간의 상관관계를 구명하였다. 외관인자들간에는 높은 상관관계를 보였으나, 외관인자들과 밀도, 외관인자들과 당도, 밀도와 당도와는 매우 낮은 상관관계를 나타냈다.

• Food Science and Preservation
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• v.18 no.2
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• pp.256-265
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• 2011

To investigate the effect of a solar salt on Kimchi fermentation, Chinese cabbages were brined with four-years aged solar salt (FS), one-year aged solar salt (OS), and purified salt (PS). The Kimchi was fermented at $7^{\circ}C$ for 33 days. The changes in pH and acidity of the Kimch brined with PS was slower than those of Kimchis brined with FS and OS. In the Kimchis with FS and OS, lactic acid bacteria (LAB) counts increased from 7.10~7.22 log CFU/mL at 0 day to 9.26~9.42 log CFU/mL at 12 days, after which counts slightly decreased to 8.04~8.75 log CFU/mL by 33 days of fermentation. The LAB counts of the kimchi with PS slowly increased from 7.24 log CFU/mL at 0 day to 8.99 log CFU/mL at 27 days, after then which counts sharply decreased to 7.92 log CFU/mL by 33 days of fermentation. Yellowness (b) color values of the kimchi with PS (59.10) was higher than the Kimchi with FS (53.68) and the Kimchi with OS (53.77). Hardness of the Kimchi with FS was more firm than the other Kimchis after 33 days storage. Sensory evaluation of the Kimchi with FS showed higher score than that of the other Kimchis.

• Food Science and Preservation
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• v.16 no.2
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• pp.238-245
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• 2009

The antioxidant effects of chungkukjang, a popular fermented soybean paste in Korea, prepared with solar salt were investigated in vitro. DJI chungkukjang(DJIC) was prepared using 3%(w/w) solar salt or 3%(w/w) refined salt, and fermented by Bacillus subtilis DJI. All of DJIC with no salt, DJIC with 3%(w/w) solar salt, DJIC containing 3%(w/w) refined salt, and commercial chungkukjang were extracted with ethanol, hexane, and water. Antioxidative activities were measured by 1,1-diphenyl-2-picryl hydrazyl(DPPH) free-radical generation, nitrite scavenging activity, peroxide value in the presence of linoleic acid, and the Rancimat test, in comparison with the commercial antioxidant butylated hydroxytoluene(BHT). Ethanol chungkukjang extracts showed the highest antioxdative capacities, whereas DPPH free-radical generation and scavenging activities, and linoleic acid peroxide values of DJIC extracts prepared using solar salt, and salt-free DJIC, showed the greatest values. In addition, extracts of DJIC prepared using solar salt had the highest antioxidant indices. Antioxidative activities were higher in DJIC extracts than in those of commercial chungkukjang. However, the antioxidative capacities of DJIC prepared using solar salt and DJIC with no added salt were less than those of BHT. In conclusion, these results suggest that extracts of chungkukjang prepared using solar salt are useful nutritional antioxidants and that dietary supplementation with such materials would decrease oxidative stress.

• Journal of Bio-Environment Control
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• v.6 no.2
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• pp.71-79
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• 1997

Commercial Bio- Green(B.G.) functional water was manufactured through a series of processes : water - ultra-purification - adding catalysts - energy imprinting fermenting with energized water ＋ zeolite and others ＋ photosynthetic bacteria in fermenter longrightarrow filtering. Control(0), 5 or 10 liters per plant of B.G. functional water were supplied to the orchard soil under canopy of 10 year- old ‘Tsugaru’/M26 apple trees on March 20, May 20 and June 20, 1995, respectively. pH and content of Ca and Mg of orchard soil were increased by supply with B.G. functional water. However, P$_2$ $O_{5}$, K, and B contents were not influenced by the treatment. At harvest time soluble solid content of flesh tissue and anthocyanin of fruit skin were increased by the treatment. B.G functional water treatment showed higher root activities, and photosynthesis of leaves than that of control. Also B.G. functional water treatment enhanced Ca content in fruit skin and flesh tissues, whereas not affected N, K, and Mg contents. During storage at 4$^{\circ}C$ cold room, the more volume of B.G. functional water supply showed lower bitter pit symptom. Respiration and ethylene evolution in fruit decreased, while fruit firmness increased by the treatment during storage.

• Food Science and Preservation
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• v.19 no.5
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• pp.757-766
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• 2012

The SSH100-10 bacterial strain, which exhibits strong antifungal (anti-mold and anti-yeast) activity, was isolated from traditional korean soysauce aged 100 years. The strain was identified as Bacillus velezensis based on Gram-staining, the biochemical properties and 16S rRNA gene sequence determination. B. velezensis SSH100-10 showed strong proteinase activity and NaCl tolerance, but did not produce enterotoxin. Two-antifungal compounds from B. velezensis SSH100-10 were purified using SPE, preparative HPLC, and reverse phase-HPLC. The purified antifungal compounds were identified as $C_{14}$ and $C_{15}$ iturin through MALDI-TOF-MS and amino acid composition analysis. The stability characteristics of the antifungal compounds after temperature, pH, and enzyme treatments suggested that B. velezensis SSH100-10 produced more than two antifungal compounds; pH-stable $C_{14}$ iturin A and $C_{15}$ iturin A, and unidentified pH-unstable compounds. The results suggested that B. velezensis SSH100-10 can be used in soybean fermentation as a starter. Moreover it has potential as a biopreservative in the food and feed industry and as a biocontrol agent in the field of agriculture.