• Journal of Radiation Protection and Research
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• v.42 no.4
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• pp.197-204
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• 2017

Background: X-ray imaging detectors for the nondestructive cargo container inspection using MeV-energy X-rays should accurately portray the internal structure of the irradiated container. Internal and external factors can cause noise, affecting image quality, and scattered radiation is the greatest source of noise. To obtain a high-performance transmission image, the influence of scattered radiation must be minimized, and this can be accomplished through several methods. The scatter rejection method using an anti-scatter grid is the preferred method to reduce the impact of scattered radiation. In this paper, we present an evaluation the characteristics of the signal and noise according to physical and material changes in the anti-scatter grid of the imaging detector used in cargo container scanners. Materials and Methods: We evaluated the characteristics of the signal and noise according to changes in the grid ratio and the material of the anti-scatter grid in an X-ray image detector using MCNP6. The grid was composed of iron, lead, or tungsten, and the grid ratio was set to 2.5, 12.5, 25, or 37.5. X-ray spectrum sources for simulation were generated by 6- and 9-MeV electron impacts on the tungsten target using MCNP6. The object in the simulation was designed using metallic material of various thicknesses inside the steel container. Using the results of the computational simulation, we calculated the change in the scatter-to-primary ratio and the signal-to-noise ratio improvement factor according to the grid ratio and the grid material, respectively. Results and Discussion: Changing the grid ratios of the anti-scatter grid and the grid material decreased the scatter linearly, affecting the signal-to-noise ratio. Conclusion: The grid ratio and material of the anti-scatter grid affected the response characteristics of a container scanner using high-energy X-rays, but to a minimal extent; thus, it may not be practically effective to incorporate anti-scatter grids into container scanners.

• 한국지구물리탐사학회:학술대회논문집
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• 1999.08a
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• pp.48-64
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• 1999

For quantitative evaluation of geotechnical engineering properties such as rippability and diggability, clear interpretation on the subsurface velocity structures should be preceded by figuring out top soil, weathered and soft rock layers, shape of basement, fracture zones, geologic boundary and etc. from the seismic refraction data. It is very important to set up suitable field parameters, which are the configuration of profile and its length, spacings of geophones and sources and topographic conditions, for increasing field data quality Geophone spacing of 3 to 5m is recommended in the land slope area for house land development and 5 to 10m in the tunnel site. In refraction tomography technique, the number of source points should be more than a half of available channel number of instrument, which can make topographic effect ignorable. Compared with core logging data, it is shown that the velocity range of the soil is less than 700m/s, weathered rock 700${\~}$1,200m/s, soft rock 1,200${\~}$1,800m/s. And the upper limit of P-wave velocity for rippability is estimated 1,200 to 1,800m/s in land slope area of gneiss. In case of tunnel site, it is recommended in tunnel design and construction to consider that tunnel is in contact with soft rock layer where three lineaments intersecting each other are recognized from the results of the other survey.

• Food Science and Preservation
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• v.14 no.3
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• pp.294-300
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• 2007

Three varieties of soy sauce were prepared using saps of bamboo, xylem and gorosoe, with sea salt and bamboo salt, in May. Soy sauce was fermented in the traditional manner. Homemade soy sauce was analyzed after 3 months of aging. The pH and amino-type nitrogen content of soy sauce fermented with xylem sap and sea salt were very high, and malic acid was dominant among four types of organic acid. The content of calcium in soy sauce fermented with bamboo sap and sea salt was fourfold greater than that of the control. The contents of total amino acids in the soy sauces fermented with xylem sap and gorosoe, with the addition of sea salt instead of water, were 2-fold and 1.4-fold greater than that of ordinary soy sauce, respectively. In the DPPH assay, the antioxidant effect of soy sauce fermented with bamboo sap and sea salt was higher than that of other samples. Sensory evaluation showed that the overall acceptability of soy sauce fermented with gorosoe and sea salt was best, among the samples tested.

• Food Science and Preservation
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• v.14 no.3
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• pp.233-238
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• 2007

To develop a new quality control method for evaluation of Korean instant noodle soups, the chemical characteristics of roasted red pepper powder(RRP), mixed with red pepper seasoning oil, were investigated during storage at $65^{\circ}C$ for 6 weeks. The chemical composition was not significantly changed after 6 weeks of storage(P>0.05). The pH value decreased gradually while the acid value increased during storage. Both the American Spice Trade Association(ASTA) value that indicates redness of red pepper, and the CIE $L^*,\;a^*,\;and\;b^*$ values decreased remarkably during storage. The fatty acids of the RRP oil were mainly linoleic acid(55.1%), oleic acid(24.3%), and palmitic acid(13.9%). The composition of fatty acids was not significantly changed after 6 weeks of storage(P>0.05). In the free fatty acid(FFA) composition of the RRP oil, linoleic acid(32.4%) was the principal component. The total amount of FFA and the amount of each individual FFA increased remarkably during storage. The ratio of free unsaturated fatty acids to free saturated fatty acids increased during storage.

• Food Science and Preservation
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• v.14 no.3
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• pp.256-262
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• 2007

Grape juice, one of the most valuable fruit derived product has large amounts of phenolic compounds which provide many of the health benefits. Campbell grape juice, divided into Sample A(without seeds and stems), Sample B(with seeds only), Sample C(with seeds and stems) were processed and assessed for its components, sensorial attributes and functional properties as influenced by the addition of seeds and stems. The presence of seeds and stems in the processing of Campbell grape juice has significant effects on pH and total soluble solids($^{\circ}Brix$) but showed no significant effects on other physicochemical and color properties and corresponds to an increase in total phenolics, radical scavenging activity, total anthocyanin and total flavonoid The sensory evaluation showed that there is no significant differences among the samples but were all liked moderately to very much by the panelists. The result of this study demonstrated that seeds and stems can be included in the processing of Campbell grape juice as it enhances the juice functional properties without altering its physicochemical and sensorial properties.

• Food Science and Preservation
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• v.22 no.5
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• pp.768-777
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• 2015

Persimmon contains high levels of vitamins and phenolic compounds, as well as soluble solids, necessary for the fermentation of persimmon wine. Co-fermentation of persimmon wine was carried out using a mixed culture of Pichia anomala JK04, a Korean indigenous yeast that improves wine quality and flavor, and Saccharomyces cerevisiae Fermivin, an industrial wine yeast, in the following ratios: 9:1 (v/v), 5:5 (v/v), 1:9 (v/v) and 0:10 (v/v). During fermentation, the alcohol contents increased more slowly in samples of mixed culture than in samples of the single culture of S. cerevisiae Fermivin. The alcohol contents of all samples reached 12~13% (v/v) after 15 days. All samples of the mixed culture showed greater variety in flavor and taste than S. cerevisiae Fermivin only. In the sensory evaluation, mixed culture samples had higher scores in terms of flavor and overall preference than the single culture samples. Therefore, P. anomala JK04 is thought to improve the wine flavor of Korean domestic persimmon wine.

• Food Science and Preservation
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• v.17 no.6
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• pp.807-813
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• 2010

Muscat Bailey A grapes, one of the major grape varieties in Korea, contain 18-20% (w/w) sugars, which is less than the amount required to make red wine. In the present study, fermentation of freeze-concentrated Muscat Bailey A grape juice to $24^{\circ}Brix$ was performed using several industrial wine yeasts, including Saccharomyces cerevisiae $OC_2$, S. cerevisiae Fermivin and S. cerevisiae W-3. During fermentation, changes in the levels of soluble solids, alcohols, and yeast viable counts were monitored. Wine quality parameters including organic acid, minor alcohol, sensory score, etc. were also analyzed. Alcohol contents reached maximal levels after 9 days of fermentation, and were 12.6% (v/v) when Fermivin was used and 13% (v/v) when strains $OC_2$ and W-3 were used. No major difference between strains was apparent, except that Fermivin fermentation was somewhat slower in terms of both alcohol production and sugar consumption. Similar levels of soluble solids and total phenols were measured in wines fermented by each of the three strains. The total acid level of W-3 wine was high, whereas the alcohol content of Fermivin wine was low. Although the wines were variable in terms of acetaldehyde and minor alcohol contents, the levels of these materials were much lower than the limits set by the Korean National Tax Service. Upon sensory evaluation, $OC_2$ wine obtained the highest scores in terms of color, flavor, and overall acceptance. However, the best taste score was awarded to the Fermivin wine, which had the same flavor score as $OC_2$ wine but a slightly lower overall acceptance score.

• Food Science and Preservation
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• v.17 no.6
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• pp.826-834
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• 2010

We investigated the temperature changes during processing and quality characteristics of seven preparations of Byeok-hyang-ju described in ancient documents. During fermentation, treatments with intervals longer than 7 days to the second mashing kept temperatures below room temperature. The process with the shortest interval (2 days) between the second and third mashings maintained a preparation temperature above $28^{\circ}C$ for the longest period. As fermentation proceeded, the pH gradually decreased. Titratable acidities increased prior to the second mashing, and then decreased. Amino acid levels increased gradually during all fermentations except for that of method 5 (the lowest level of raw material addition). Ethanol content increased rapidly to the time of second mashing with all methods except method 2. This method featured a short interval between the first and second mashing. Upon sensory evaluation, the best overall acceptability was provided by method 3.

• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.51-59
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• 1998

When the contents of the constituents such as total amino acids, free amino acids, volatile organosulfuric compounds and steroidal saponins among three origins in the aerial-and underground parts of Allium victorialis, it was suggested that the characteristic components regarding to quality evaluation could be differed according to the purpose of utilization. For the utilization of amino acids, underground parts of this plant was shown to be better than aerial part. In addition, Ulung island origin was found to contain the highest amino acids content among the three origins though the difference was small. The amino acids showing remarkably high contents were appeared to be arginine, glutamine and asparagine. In the volatile organosulfuric compounds, the origina of Mt. Odae and Mt. Chiri positioned in inland showed higher contents than Ulung island origin geographically positioned in the ocean. Inland origins were shown to contain higher organosulfurie component contents in aerial parts than in underground parts while those of Ulung island origin were higher in underground parts than aerial parts. Underground parts, regarding to saponin constituents, showed higher contents than aerial parts. Underground parts of Ulung island origin were shown to contain more saponins than those of other two origins and the sequence of the contents was in the order of Ulung island>Mt. Chiri>Mt Odac.

• Fire Science and Engineering
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• v.34 no.3
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• pp.43-48
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• 2020

The purpose of this study is to develop an earth leakage alarm circuit breaker, equipped with a leakage alarming function (JER-E2S, ETECKOREA Co., Korea), and to analyze its characteristics. The developed mechanism is exclusively used for single-phase and 220 V circuits, with a rated current of 32 A, 20 A, 20 A (for restrooms), 16 A, etc. It satisfies all characteristics of existing earth leakage circuit breakers (ELB). If a fire current, which is a resistive leakage current (Igr), flows through an electric line, the device detects the leakage current in real time and warns against the leakage through a blinking LED lamp. Since the developed device displays a tolerance to a capacitative leakage current (Igc) that inevitably occurs in LED lamps, communication devices, etc., it ensures a stable power supply. In addition, the earth leakage alarm circuit breaker protects against power failure due to a momentary ground fault. Therefore, it can supply power without the risk of the circuit breaker malfunctioning due to a momentary ground fault caused by water droplets, leaves, etc. Moreover, with a standby power of less than 0.1 W, the developed earth leakage alarm circuit breaker exhibits a power saving performance that is 3~8 times greater than that of other ELBs. Installation of approximately 10 earth leakage alarm circuit breakers in one apartment household, with an area of 120 ㎡, can save 2~5 kWh per month. Therefore, the developed earth leakage alarm breaker not only satisfies the characteristics of existing earth leakage breakers, but also exhibits outstanding power supply quality since it has the functions of electric fire prevention and malfunction prevention. Therefore, this device can innovatively contribute to electric fire prevention.