• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.33-38
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• 1997

Criticality experiments with fixed neutron poison plates for water moderated and reflected low enriched(2.35 and 4.31 wt%) UO$_2$fuel rod clusters were evaluated to validate calculation techniques employed in analyzing fuel shipping and storage systems having steel, boral, or cadmium shield. Measurements were obtained for both the 2.35 wt% and the 4.31 wt% enriched rods in square pitched, water flooded lattices. The critical experiments with the 2.35 wt% enriched rods consists of three 20$\chi$ 16 or 20$\chi$ 17 fuel cluster. Critical separation were used in the experiments with the 4.31 wt% enriched fuel rods. In the experiments, the poison plates were placed on both sides of the centrally located fuel cluster. Critical separation between the three sub-critical fuel clusters were then measured for varying plate thicknesses and distances of the plates to the center fuel cluster. Calculations were performed for thirty eight critical configuration using KENO-V. a and MCNP. All of the results were within 1.23% in $\Delta$k when individually compared with the critical value of 1.0. Discrepancies of the code results are probably due to uncertainties in experiments and/or analytical modeling experiments. In general, MCNP predictions were observed to be in best agreement with the experiments.

• Agricultural and Biosystems Engineering
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• v.2 no.2
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• pp.63-68
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• 2001

The objective of this study was to develop a real-time soil moisture meter using RF impedance. The impedance suchas capacitance and resistance (or conductance) was analyzed using parallel cylinder type capacitance probe(C-probe) and Q-meter (HP4342). The capacitance and conductance of soil increased as volumetric water content increased. The 5 MHz of modified Colpitts type crystal oscillator was designed to detect the capacitance change of the C-probe with moist soil. A third order polynomial regression model was proposed to describe the relationship between RF impedance and volumetric water content. The prototype real time moisture meter consisted of the C-probe, sample container, oscillator, frequency counter and related signal processing units. The calibration equation for measurement of volumetric moisture content of soil was developed and validated. The correlation coefficient and root mean square error between measured volumetric water content by oven method and predicted values by prototype moisture meter for unknown soil samples were 0.984 and 0.032$cm^3$$cm\^3$, respectively.

• Journal of Ocean Engineering and Technology
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• v.10 no.1
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• pp.100-107
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• 1996

In this paper, we report the results of the experimental study on the flow and the mass transport around a square harbor driven by a tidal effect. The model harbor is composed of a uniform water-depth with a straight breakwater. The harbor is connected to the outer ocean by an entrance region having the same shape as the harbor. We investigated two cases, one having another breakwater in the place between the entrance region and the outer ocean, and the other without it, The surface and bottom flow patterns of the model container are visualized by using light particles and dye, respectively. It was shown that the inner harbor and the entrance region have well-organized, large vortical residual flows, and the material transport between the entrance and outer region is however significantly different for two cases; when the breakwater is built between the two regions, the transport is far better than that without it, which is clearly contrary to our common sense that the breakwater would block the dispersion of the materials between the harbor and the outer ocean.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.633-644
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• 2020

Rice paper is an element of Vietnamese cuisine that can be used to wrap vegetables and meat. Rice and starch are the main ingredients of rice paper and their mixing ratio is important for quality control. In a commercial factory, assessment of food safety and quantitative supply is a challenging issue. A rapid and non-destructive monitoring system is therefore necessary in commercial production systems to ensure the food safety of rice and starch flour for the rice paper wrap. In this study, fluorescence hyperspectral imaging technology was applied to classify grain flours. Using the 3D hyper cube of fluorescence hyperspectral imaging (fHSI, 420 - 730 nm), spectral and spatial data and chemometric methods were applied to detect and classify flours. Eight flours (rice: 4, starch: 4) were prepared and hyperspectral images were acquired in a 5 (L) × 5 (W) × 1.5 (H) cm container. Linear discriminant analysis (LDA), partial least square discriminant analysis (PLSDA), support vector machine (SVM), classification and regression tree (CART), and random forest (RF) with a few preprocessing methods (multivariate scatter correction [MSC], 1^st and 2^nd derivative and moving average) were applied to classify grain flours and the accuracy was compared using a confusion matrix (accuracy and kappa coefficient). LDA with moving average showed the highest accuracy at A = 0.9362 (K = 0.9270). 1D convolutional neural network (CNN) demonstrated a classification result of A = 0.94 and showed improved classification results between mimyeon flour (MF)1 and MF2 of 0.72 and 0.87, respectively. In this study, the potential of non-destructive detection and classification of grain flours using fHSI technology and machine learning methods was demonstrated.

• Korean Journal of Environment and Ecology
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• v.28 no.3
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• pp.357-364
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• 2014

This study aimed to determine effects of the use of water-retention additive, hydrophilic polymer, for extensive green roofs on growth of Juniperus chinensis var. sargentii and Euonymus fortunei 'Emerald and Gold' for woody plants, and Carex kobomugi and Carex pumila for herbaceous plants. Five different contents of hydrophilic polymer including 0% (Control), 1.0%, 2.5%, 5.0%, and 10% (polymer: medium (w/w), dry weight basis) were added to each of the container filed with a 100 kg of growth medium. Ten of plants were transplanted in each of square container ($1m(L){\times}1m(W){\times}0.3m$ (H)) built on the roof platforms in randomized complete block design in the $20^{th}$ of May, 2013. In results, excessively high volumetric soil water content, about 97-98%, was found in the substrate under elevated hydrophilic polymer concentration of at least 2.5%, during the entire growing period. The moisture content of the substrate containing 1.0% of hydrophilic polymer was higher about 20% in the range between 70% and 80%, compared tho that of Control substrate in the range between 50% and 60%, for 27 days after transplanting prior to abundant rainfall, indicating that the application of hydrophilic polymer to the extensive green roof substrate is effective to eliminate drought condition by retaining water in the substrate. Euonymus fortunei 'Emerald and Gold' and Carex kobomugi resulting in higher plant growth with 2.5% than those of the other treatment plants. Juniperus chinensis var. sargentii was observed the highest growth under 1.0% hydrophilic polymer treatement, and Carex pumila was founded the best growth with Control respectively. Plants that grown in both the 1.0% and 2.5% hydrophilic polymer survived all, while the plants that grown in the 5.0% and 10% hydrophilic polymer died after 3 months. These results suggest that advantage of the addition of hydrophilic polymer may be greater in drought-tolerant plants, but the mixture proportion of hydrophilic polymer should be determined according to the different features of the plant species being grown.

• Journal of Chest Surgery
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• v.17 no.1
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• pp.157-166
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• 1984

These biologic test procedures are designed to test the suitability of P.V.C. made in Korea intended for parenteral preparation, which were based on the U.S. Pharmacopeia XIX "Biologic Test-Plastic Container", Official from July 1, 1975. Healthy adult human blood and rabbits weighing 2\ulcorner.2Kg were used for test materials. Sample P.V.C. were sampled from the medical equipments made in Korea randomly and Control P.V.C. were sampled from the standardized Cobe and Polystan P.V.C. tubes. P.V.C. extract was prepared from a homogeneous P.V.C. samples by incubating 60 square centimeters of the sample per 20 millimeters of sterile pyrogen-free saline at 70\ulcorner for 72 hours or autoclaving at 120\ulcorner for 1 hour. The Implantation Test was designed to evaluate the reaction of living tissue to the plastic by the method of the implantation of the Sample itself into animal tissue. The Systemic Injection Test, the Intracutaneous Test, and the remainders were designed to determine the biological response of animals to plastics by the single-dose injection of specific extracts prepared from a Sample. The results are as follows; 1.Implantation Test - No significant difference for reactions was noted between the Sample treated animal and the Control after 72 hours of implantation. 2.Systemic Toxicity Injection Test - No sign of toxicity and/or death immediately after injection and at 4, 24, 48 hours respectfully after injection. 3.Intracutaneous Test - None of the animals treated with the Sample showed a significantly greater reaction than the observed in the animals treated with Blank. 4.Pyrogen Assay-Only one animal treated with the Sample showed the maximal rise of rectal temperature about 0.2\ulcorner after 3 hours of injection, but remainders showed no change. 5.Hemolytic Index - The positive Control tube of distilled water exhibited complete hemolysis while the negative Control tube and P.V.C. extract were negative demonstrating no hemolysis. 6.Cell Morphology of Erythrocytes and Leukocytes on Stored, Heparinized Human Blood -- There was no significant difference in the morphology of either the Control or Sample extract. 7.Clotting Mechanism of Human Blood in vitro - After allowing to the P.V.C. extract at room temperature for 5 Hours and at 10\ulcorner for 24 hours, there was no appreciable difference in Prothrombin Time under these conditions. 8.Clotting Mechanism of Rabbit in vivo - At the termination of 5 days after intraperitoneal injection of the P.V.C. extract, no significant changes in Clotting Time were observed. According to the above results, it could be concluded that the P.V.C. made in Korea was acceptable for parenteral preparation, especially treated with physiologic saline and/or human blood.man blood.

• Food Science and Preservation
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• v.19 no.1
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• pp.47-53
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• 2012

UV light irradiation is known to give beneficial effects on fresh produce preservation. A container system equipped with UV-LED was fabricated for storing cherry tomatoes under computer-controlled conditions of intermittent on-off cycles (1 hour on/1 hour off). Wavelength (365 and 405 nm) and physical location of the LED (2 and 5 cm above fruit) were studied as variables affecting the respiration, ethylene production and quality preservation of the fruits at 10 and $20^{\circ}C$. 365 nm wavelength gave much higher radiation intensity than 405 nm, and intensity on surface decreased in inverse proportion to square of distance from LED. When compared to non-irradiated control, UV-LED irradiation decreased the respiration by 5-10% at $10^{\circ}C$ while there was no obvious effect at $20^{\circ}C$. Ethylene production was reduced when the fruits were placed at 5 cm distance, while there was no significant difference from control at 2 cm location. The reduction of ethylene production at 5 cm was more pronounced at $20^{\circ}C$. UV-LED irradiation was shown to have delayed increase or lower concentration in carotenoids compared to control treatment. Any negative effect of UV-LED irradiation on ascorbic acid content and firmness was not observed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.4
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• pp.39-47
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• 1982

Geotextile effects as reinforcement and vertical drain materials are studied through the laboratory model embankments on weak clays. The experiments are carried out in four stages; no woven fabrics between clay-crushed stone boundary, fabrics between boundary with no initial pretensioning of fabrics, and fabrics between boundary with two different initial pretensionings of fabrics. In all stages, vertical drains utilizing non-woven fabrics are installed in the clay layer in square pattern to accelarate the consolidation. The experimental model has plane dimensions of $32cm{\times}330cm$. The height for the clay container is 60 cm. The 47 cm height of crushed stone embankment is constructed over the 50 cm deep clay layer. The time dependent pore pressures are measured utilizing the 8 piezometers installed symmetrically on both sides of the wall at different heights. The time dependent deformations are measured utilizing the LED indicating lamp matrix inserted in the crushed stone embankment and the dialgauges put on top of the clay layer where the crushed stones are not laid. The measurements are carried out for 10 days which is equivalent to the time required for the primary consolidation. Through the experimental study, an analytical procedure is developed to predict the time dependent embankment settlement even if the top of the clay layer is reinforced with woven fabrics. This can be done through measuring the maximum pore pressures developed in the clay layer and comparing with the theoretical maximum pore pressures when no reinforcing fabrics are employed.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.670-676
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• 2016

In this study, we analyzed the utensils, covers and mats that were used for making meju, the shape of meju, and the heating method used for making meju from the 225 ways of preparing jang mentioned in the 32 volumes of the ancient cook books from 530 AD to 1950. The heating method of traditional meju bean and starch included 57 kinds of steaming, 59 of boiling, 21 of roasting + boiling, and 2 of cooking. The shape of meju included 41 kinds of egg, 27 of ball, 22 of lump, a kind of doughnut, 8 kinds of hilt, 6 of flat, 4 of chip, and a kind of square. Among the 72 gochoojang meju, the heating method of bean included 9 kinds of boiling, and 6 kinds of steaming; whereas the heating method of starch included 19 kinds of steaming of dough, 11 of rice cooking, and 5 of boiling of dough. The utensils for molding of bean meju were 49 kinds of straw sack, 14 of round straw container, 11 of heating bed, 7 of large straw bowl or Japanese-snailseed, 5 of jar, 4 of ditch, 3 of straw bowls, 2 of pottery steamer of dough, 2 of gourd, and a kind of long round bamboo bowl and sack of straw. The cover and the mat used for molding of meju included 36 kinds of straw, 17 kinds of paper mulberry leaf, 15 of wide straw seat, 14 of mugwort, 11 of pine tree leaf, 10 of soybean leaf, 6 of cocklebur leaf, 6 of sumac leaf, 6 of barley straw, 6 of mulberry leaf, 5 of fallen leaf, 5 of cogon grass, 4 of reed seat, 3 of scrap of cloth, 2 of Indian bean tree leaf, a kind of reed. There were only 5 kinds of hanging.

• Korean Journal of Food Science and Technology
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• v.52 no.5
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• pp.560-563
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• 2020

Cold plasma has been applied to improve quality of food product; however, studies on its effects on microbial and physicochemical qualities of rice noodles are rarely conducted. In this study, changes in the quality characteristics of rice noodles treated by cold plasma were determined. Cold plasma was generated in a square-shaped plastic container (250 W, 15 kHz, ambient air), and dielectric barrier discharge plasma treatments were applied to rice noodle samples for 0, 10, or 20 min. Rice noodles inoculated with either Bacillus cereus or Escherichia coli O157:H7 were subjected to plasma treatment for 20 min, and the approximate bacterial count reduction were 4.10 and 2.75 log CFU/g, respectively. The Hunter color values of the sample were increased after cold plasma treatment. Peroxide values and thiobarbituric acid reactive substance (TBARS) were increased with an increase in cold plasma treatment time. Futhermore, lipid oxidation was enhanced. Although further studies are warranted to evaluate changes in chemical qualities, such as lipid oxidation of rice noodles, induced by cold plasma, the results suggest that cold plasma can improve the microbial and physical qualities of rice noodles.