• Food Science and Preservation
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• v.24 no.2
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• pp.168-180
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• 2017

This study was performed to determine the rapid thawing method for reducing the thawing time of frozen pork loins and to examine the effects of supercooling on the microbiological, physicochemical, and sensory qualities of fresh and frozen-thawed pork during storage at -1.5, 4, and $15^{\circ}C$. Forced-air thawing at $4^{\circ}C$ was the most time-consuming process, whereas radio frequency thawing time was the shortest by dielectric heating. The supercooling storage temperature was chosen to be $-1.5^{\circ}C$ because microstructural damages were not observed in the pork sample after cooling at $-1.5^{\circ}C$ for 24 h. Fresh or frozen-thawed pork loins stored at $-1.5^{\circ}C$ had lower drip loss and total volatile base nitrogen, thiobarbituric acid-reactive substance, and Hunter b* levels than loins stored at 4 and $15^{\circ}C$. In addition, the least degree of increase in preexisting microorganisms counts of the fresh or frozen-thawed pork loin samples was obtained during supercooled storage at $-1.5^{\circ}C$. Sensory quality results of fresh and frozen-thawed pork loin samples stored at $-1.5^{\circ}C$ showed higher scores than the samples stored at 4 and $15^{\circ}C$. These data indicate that supercooling at $-1.5^{\circ}C$ in the meat processing industry would be effective for maintaining the quality of pork meats without ice crystal nucleation and formation.

• The Journal of the Petrological Society of Korea
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• v.23 no.3
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• pp.239-247
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• 2014

The (U-Th)/He dating utilizes the production of alpha particles ($^4He$ atoms) during natural radioactive decays of $^{238}U$, $^{235}U$ and $^{232}Th$. (U-Th)/He age can be determined from the abundances of the parent nuclides $^{238}U$, $^{235}U$ and $^{232}Th$ and the radiogenic $^4He$. Because helium is one of the noble gases (non-reactive) with a relatively small radius, it diffuses rapidly in many geological materials, even at low temperatures. Therefore, ingrowth of $^4He$ during radioactive decay competes with diffusive loss at elevated temperatures during the geologic time scale, determining the amount of $^4He$ existing today in natural samples. For example, He diffusion in apatite is known to be very rapid compared to that in most other minerals, causing a significant diffusive loss at ${\sim}80^{\circ}C$ or higher. At ${\sim}40^{\circ}C$, He diffusion in apatite becomes slow enough to preserve most $^4He$ in the sample. Thus, an apatite's (U-Th)/He age represents the timing when the sample passed through the temperature range of $80-40^{\circ}C$. The crustal depth corresponding to this temperature range is called a "partial retention zone." Normal closure temperatures for a typical grain size and cooling rate are ${\sim}60-70^{\circ}C$ for apatite and ${\sim}200^{\circ}C$ for zircon and titanite. Because the apatite He closure temperature is lower than that of most other thermochronometers, it can provide critical constraints on relatively recent or shallow-crustal exhumation histories.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.5
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• pp.394-402
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• 2021

The entry of an aging society and the extension of human life expectancy, the increasing interest in women's social advancement and men's appearance, and the natural interest in K-culture through media media, while receiving worldwide attention, Focus on K-Bueaty. Recently, looking at the occupation of the medical tourism field, in the case of aesthetic medicine tourism such as molding and dermatology, it has gained popularity not only in Asia such as China and Japan, but also in North America and Europe. The first external confirmation of human aging is the wrinkles on the skin of the face. Clean, wrinkle-free, elastic and healthy skin is a desire of most people. Skin condition and condition such as focused ultrasonic stimulation (HIFU: High Intensity Focused Utrasound) and low frequency, high frequency (RF: Radio Frequency), galvanic therapy using microcurrent, cryotherapy using rapid cooling, etc. Depending on the method of management, the effect of the treatment differs depending on the output and the stimulation site, etc., even in the treatment of medical equipment and beauty equipment using the same mechanism. In this research, in order to develop invasive high-frequency dermatological devices using a large number of beauty medical devices and microneedles of beauty devices, the international standards IEC 60601-2 (standards for individual medical devices) and MFDS (Ministry of) We designed and developed a high-frequency output device in compliance with the high-frequency stimulation standard announced in the Food and Drug Safety (Ministry of Food and Drug Safety). The circuit design consists of an amplifier (AMP: Amplifier) using Class-A Topology and a power supply device using Half-Bridge Topology. As a result of measuring the developed high-frequency output device, an average efficiency of 63.86% was obtained, and the maximum output was measured at 116.7W and 50.67dBm.

• Journal of Chest Surgery
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• v.2 no.1
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• pp.85-104
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• 1969

This experiment was carried out to study the effect of rapid hemorrhage on cardiopulmonary hemodynamics of the cooled dogs. Hypothermia was induced by means of body surface cooling with ice water. Lowest esophageal temperatures ranged from 24 to 26 degree. Dogs were bled via the femoral artery into a reservoir in amount of the equivalent blood volume of 3% of body weight of the dogs. Some dogs were reinfused with the same amount of blood which they lost and others infused with 5% dextrose solution. Fourty adult mongrel dogs were divided into three groups: group I[15 dogs]; dogs were bled in normothermic state. Five dogs had no further treatment, but five dogs were reinfused with blood and five infused with 5% dextrose solution 30 minutes after bleeding. GroupII[10 dogs]; dogs were bled as group I after having been cooled. Five dogs were reinfused with blood as group I. Group III[15 dogs]; dogs were first bled and then cooled. Reinfusion procedures were the same as in group l Results were as follow: 1. The heart rate showed a slight decrease after bleeding in group I and then increased over the control level after 60 minutes. After reinfusion and infusion, the heart rate was also increased gradually and after three hours almost returned to the control level. In group II and groupIll, the heart rate decreased remarkably and after reinfusion showed a light increase but after infusion tended to decrease cotinually. 2. The stroke volume showed remarkable decrease after bleeding in group I., and recovered to control level after reinfusion and infusion,and then gradually decreased again. In group III, the stroke volume showed no remarkable change after hypothermia, and tended to decrease after reinfusion. In group III, the stroke volume decreased remarkably after bleeding and hypothermia,and clearly increased after reinfusion and infusion and then returned to control level. 3. Femoral mean pressure declined very rapidly and significantly right after bleeding and showed a remarkable prompt rise after reinfusion and infusion in group I [67% recovery]. On the other hand, it declined remarkably after hypothermia and bleeding and showed a slight rise after reinfusion and infusion in group II[46% recovery] and III [41% recovery]. 4. Venous pressure declined slightly after bleeding and tended to return to the control level after reinfusion and infusion,in group I. In group II, it did not change significantly during hypothermia but showed a slight decline after bleeding and returned toward control level after reinfusion. In group III, it declined slightly after bleeding and showed no significant change after hypothermia and rose over the control level after reinfusion and infusion. 5. Right ventricular systolic pressure decreased markedly after bleeding and then increased progressively after 30 minutes. It increased after reinfusion and infusion as well, approaching the control level in group I. In group II, it showed no significant change during hypothermia, but decreased remarkably after bleeding and then returned to near control level after reinfusion. In group III, it was decreased markedly after bleeding but did not change significantly during hypothermia and showed a slight increase after reinfusion. 6. The respiratory rate increased gradually after bleeding and decreased gradually after reinfusion but did not return to the control level, whereas it decreased near to the control level after infusion,and tended to increase in group I. In group II, it decreased significantly after hypothermia and bleeding but returned near to the control level after reinfusion. In group III, it showed a remarkable decrease after hypothermia and increased slightly after reinfusion and infusion but did not returned to the control level. In group I, the tidal volume decreased slightly after hemorrhage, and increased gradually to near the control level after 3 hours following reinfusion.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47
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• pp.15-32
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• 2002

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s-1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great progress and success was obtained in development of high-quality japonica cultivars and quality evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice cultivars and special rices adaptable for food processing such as large kernel, chalky endosperm, aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer, Recently, new special rices such as extremely low-amylose dull or opaque non-glutinous endosperm mutants were developed. Also, a high-lysine rice variety was developed for higher nutritional utility. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and texture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak, hot paste and consistency viscosities of viscosities with year difference. The high-quality rice variety "IIpumbyeo" showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic microscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high probability of determination. The $\alpha$-amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were IIpumbyeo, Chucheongyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tonsil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice breed. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large grain rices showed better suitability far fermentation and brewing. The glutinous rice were classified into nine different varietal groups based on various physicochemical and structural characteristics of endosperm. There was some close associations among these grain properties and large varietal difference in suitability to various traditional food processing. Our breeding efforts on improvement of rice quality for high palatability and processing utility or value-adding products in the future should focus on not only continuous enhancement of marketing and eating qualities but also the diversification in morphological, physicochemical and nutritional characteristics of rice grain suitable for processing various value-added rice foods.ice foods.