• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.342-347
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• 2006

Korean pear juice heat-treated at various temperatures (110, 120, 130, 140, and $150^{\circ}C$) and times (1, 2, 3, 4, and 5 hr) was analyzed to determine total polyphenol, total flavonoid, free sugar, and 5-HMF contents, and DPPH free radical-scavenging activity. Total polyphenol, total flavonoid, and 5-HMF contents, and antioxidant activities increased, whereas fructose content decreased with increasing heat treatment temperature and time ($p\;{\pm}\;0.007\;mg/g$ with treatment at $150^{\circ}C$ for 1 hr (unheated pear juice: $0.233\;{\pm}\;0.024\;mg/g$). Highest total flavonoid content was $561.49\;{\pm}\;16.93\;{\mu}g/g$ with treatment at $150^{\circ}C$ for 4 hr (unheated pear juice: $1.50\;{\pm}\;0.20\;{\mu}g/g$). $IC_{50}$ value was highest, $1.93\;{\pm}\;0.01\;mg/g$, at $150^{\circ}C$ for 2 hr, whereas that of unheated pear juice was $64.58\;{\pm}\;0.99\;mg/g$. Glucose content was not affected by treatment conditions, whereas fructose content decreased with treatment at $140^{\circ}C$ for 3 hr. Highest 5-HMF content was $5,594.93\;{\pm}\;6.43\;ppm$ at $150^{\circ}C$ for 5 hr (unheated pear juice: $2.04\;{\pm}\;0.21\;ppm$). Correlation coefficients were observed among total phenolic, total flavonoid, and antioxidant activities, and between fructose and 5-HMF at significance level (p<0.001).

• Journal of the East Asian Society of Dietary Life
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• v.25 no.6
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• pp.1007-1017
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• 2015

This study compared the physicochemical characteristics, proximate composition, taste compound, and antioxidant properties of Sikhye prepared with berries. Proximate composition and color were significantly different depending on the type of berry, whereas crude fat content and pH were not. The highest brix degree was $18.92^{\circ}Bx$ in strawberry Sikhye. Total free sugar, glucose, and fructose contents were highest in blueberry Sikhye. Titratable acidity, total acidity, and organic acid contents were highest in raspberry Sikhye. Analysis of relative antioxidative properties indicated that bokbunja Sikhye had the highest total polyphenol, flavonoid, and anthocyanin contents, highest DPPH radical scavenging ability, and highest reducing power and ferric reducing abilities in plasma. Principal component analysis suggests that bokbunja Sikhye has strong antioxidant and sweetness properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.267-273
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• 1996

열풍건조 전 전처리로서 $50^{\circ}C의$ 2%(w/v)가용성 전분용액에서 20분간 침지를 한 처리구와 건조 후 분말 입자크기가 $40^{\circ}C,$ 90%RH의 저장 중 분말양파의 물리적 성질에 미치는 영향을 조사하였다. 저장 중 수분흡수는 처리구와 대조구 모두 분말양파의 입자 크기에 관계없이 저장 초기에 빠르게 이루어진 후 저장시간이 지남에 따라서 둔화되었다. 처리구가 대조구에 비하여 저장중 수분흡수가 작게 나타났다. 처리구의 경우 분말입자가 큰 -24+60 mesh의 수분흡수는 저장 6시간 후 처리구와 대조구의 덩어리 형성 정도는 각각 12.26과 60.1%이었다. 입자 크기에 다른 덩어리 형성 정도는 처리구에서 저장 1시간 후 2.28%과 23.6%로 나타났다. 겉보기 밀도에서는 처리구가 대조구에 비하여 전반적으로 높은 값을 나타내었으며 처리구의 경우 수분흡수가 0.03에서 0.12g수분/g고형분으로 늘어남에 따라서 겉보기 밀도는 입자가 큰 분말은 0.49에서 0.38g/㎤이였으며 입자가 작은 분말은 0.31에서 0.29g/㎤로 나타났다. 압축성에서는 입자 크기가 크고, 수분흡수가 많이 이루어진 분말일수록 도한 대조구가 처리구 보다 응집성질을 가지게 되므로 높은 값을 나타내었다. 이완상수에서는 입자가 큰 처리구의 경우 수분흡수가 3.0과 12.1%이루어 진 것을 비교하면 각각 2.45와 2.01로 나타났다. 이는, 수분흡수가 높아짐에 따라서 고체 성질이 줄어들게 됨으로써 이완상수값이 낮아지기 때문이다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.5
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• pp.687-697
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• 1998

In spite of increasing public concern about the human exposure to electric and magnetic fields(EMFs), there is little information about the EMF levels in the vicinity of power facilities and of home appliances. To provide such information, a nationwide survey for EMFs near overhead transmission lines has been conducted. The median values of the electric fields and magnetic fields of 153 transmission lines were 0.47 kV/m and 11.6 mG, respectively. The maximum values were 3.16 kV/m and 125 mG. These were low values in comparison with any EMF guidelines or standards of advanced contries. Measurements of the magnetic fields of typical home appliances and daily human exposure records have been also conducted. These magnetic field values were comparable to those of the transmission lines.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.2 s.105
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• pp.221-227
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• 2006

The SAR evaluation system with 9 stationary probes inserted into the object to be surveyed can calculate area SAR value based on the 9 measured electric field data. The results can be acquired in a few seconds by converting obtained area SAR to the volume SAR. The system can be very useful tool in the stages of handset development for mobile communication as well as in the handset production line because of its rapid SAR measurement ability. The validity of the measurement system is checked by showing that the measured SAR values agree well with reference SAR values suggested in the reference documents.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.575-581
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• 1990

The existence of the equivalent point for a thermal processing system was demonstrated using arbitrarily chosen ideal direct heating curves. i.e. isothermal heating curves at $120^{\circ}C$ for 10min and at $135^{\circ}C$ for 10sec. Under these conditions, G-values and F-values were calculated at various values of Ea- and z-values by applying the Arrhenius and the Bigelow models respectively. The equivalent time and equivalent temperature were determined by both line intersection and linear regression methods. The equivalent points estimated by both the line intersection and the linear regression methods were consistent and their values were the same as the heating time and temperature of the ideal direct heating curves.

• Food Science of Animal Resources
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• v.27 no.2
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• pp.216-221
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• 2007

This experiment was carried out to investigate characteristics of pork quality according to various producing district. The results of whole component analysis of pork according to diverse producing district were showed high level of fat content in Jeju island-belly and shoulder loin than other pork samples. And saturated fatty acid contents of Jeju island-belly and shoulder loin of pork were showed 46.6 and 41.6%, respectively, and unsaturated fatty acid contents of Jeju island-belly and shoulder loin of pork were showed 50.3 and 58.4%, respectively. Chungbuk-pork was relatively showed high level of cholesterol content than other pork samples. On the other hand, cholesterol contents of Jeju island-belly and shoulder loin of pork were showed 565.6 and 507.6 ${\mu}g/g$, respectively. Skatole contents of Jeju island-belly and shoulder loin of pork were showed low level(0.013 and 0.065 ${\mu}g/g$) than other pork samples. This results mean that Jeju island-belly and shoulder loin of pork have less order than other pork samples. The chewiness of texture that consumers feel the biggest difference in palatability of meat showed significantly high level(376.5 g) in Jeju island-belly of pork(p<0.05). This result represent that Jeju island-belly of pork have the best sense of the texture than other pork samples. $L^*$(lightness) value of ground pork was generally showed high value in belly than shoulder-loin of pork. However, $a^*$(redness) value of ground pork showed high value in shoulder-loin than belly of pork. And there was no significant difference in $b^*$(yellowness) value among the samples(p>0.05). The results of sensory test(taste, flavor, texture and palatability) from pork according to various producing district showed good flavor and palatability in Jeju island-belly of pork but there was no significant difference among the samples(p>0.05).

• Research in Plant Disease
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• v.12 no.1
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• pp.32-39
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• 2006

This study has been conducted to investigate the responses of various isolates of four Colletotrichum species such as C. gloeosporioides, C acutatum, C. coccodes, and C. dematium isolated from infected tissues of several crops to fungicides such as carbendazim, carbendazim+diethofencarb, four protective fungicides, and three ergosterol biosynthesis-inhibiting (EBI) fungicides. All the isolates of C. acutatum showed $EC_{50}$ values in a range of 0.001-3.040 ${\mu}g/ml$ against carbandazim, a benzimidazole fungicide. As for the response to carbendazim, the isolates of C. gloeosporioides obtained from pepper, apple, and strawberry were clearly divided into two groups, resistant or sensitive isolates. All the resistant isolates showed $EC_{50}$ values above 1000 ${\mu}g/ml$, whereas the sensitive isolates had lower $EC_{50}$ values than 0.550 ${\mu}g/ml$. The isolates of C. gloeosporioides exhibited a negative cross resistance between carbendazim and diethofencarb (a N-phenylcarbamate fungicide), but isolates of C. acutatum did not. Toward carbendazim, C. coccodes and C. dematium isolates showed a similar response to C. acutatum isolates and the sensitive isolates of C. gioeosporioides, respectively. As for response of Protective fungicides, all the isolates of C. acutatum showed a more resistant reaction than all the isolates of C. gloeosporioides. However, there was no difference among 4 species of Colletotrichum against EBI fungicides.

• Analytical Science and Technology
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• v.19 no.3
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• pp.203-210
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• 2006

The determination of trace selenium in milk powder has been studied by octopole reaction cell(ORC)-ICP-MS. The interferences by polyatomic ions and other concomitant molecular species could be removed remarkably by using $H_2$ as reaction gas in ORC. Compared to the normal mode (no cell gas), the $H_2$ cell gas mode improved the accuracy and precision. The quantitative result was average 102.7% and it was slightly higher than certified standard value of milk powder and the RSD was 7.6%.

• Korean journal of applied entomology
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• v.32 no.2
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• pp.139-150
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• 1993

This study was conducted to investigate the effect of 20-hydroxyecdysone on diapausing pupae of Hyphantna cunea. Treatment of 20-HE at the dosage of 5 $\mu$ g or higher/g live weight terminated diapause in about 50% of Hyphantna cunea pupae treated, and some malformed adult emerged at dosages of 10 or 12.5 $\mu$g of 20-hydroxyecdysone/g live wt. The maximum concentration of 20-hydroxyecdysone in the whole body of normally developing pupae was about 3.2 $\mu$g/g on the 6th day after pupation, and in that of diapausing pupae treated with 20 -HE about 4.1 $\mu$g/g on the 6th day after the treatment. But diapausing pupae showed a low level( 1.7 $\mu$g/g) of maximum 20-HE concentration. In diapausing pupae treated with 20- HE, glycongen content was lower than in normally developing pupae, but the changing pattern was similar to that observed in normally developing pupae. Glucose(and/or sorbitol) and trehalose content of 20-HE-injected pupae reached the maximum value on the 6th day after the injection, which were higher than those of normally developing pupae. The amount of soluble haemolymph proteins was lower but the total soluble protein content of haemolymph-rernoved whole body was higher in 20-HE-injected pupae than that in normally developing pupae.