• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.4
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• pp.358-365
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• 2019

An agrivoltaic systems (AVS) is mixed systems associating photovoltaic panels (PVPs) and crop cultivation at the same time on the given land area. It is receiving attention to improve rural economy. However, it is likely that, the crop yield should be decreased due to the reduced absorption of solar radiation by leaves. Thus, before popularizing the AVS, it is necessary to comprehend the degree of shading by PVPs in AVS. In this study, the change of radiation condition under AVS mimic shading net was investigated. The minimum and maximum of difference of photosynthetically active radiation (PAR) between under and outside shading net were 3.03 mol/㎡/day on a cloudy day and 17.08 mol/㎡/day on a sunny day. This difference decreased when the ratio of diffuse irradiance to global irradiance increased. Such a shading effect resulted in the increase of rice height and decrease of rice tillering.

• KSBB Journal
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• v.20 no.2 s.91
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• pp.93-99
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• 2005

Polyunsaturated fatty acids, that is PUFAs, are important constituents of membranes particularly found in the retina and central nervous system. In microorganism-based PUFAs biosynthesis, the genus Thraustochytrids is well evaluated for their potential as a promising candidate in the practical production of PUFAs, such as AA and DHA. In this study, we attempted to optimize a method of total nucleic acid extraction from this microorganism as a preliminary experiment. Using the extracted nucleic acid and degenerated primers for direct PCR, we isolated a $\Delta5$ desaturase gene that contained 1320-nucleotide and encoded 439 amino acids. This gene exhibited an expected function, when expressed in P. pastoris in the presence of appropriate exogenous substrate, as an evidence for $\Delta5$ desaturase activity (conversion of DGLA to AA). These results and information could provide a basis for the construction of engineered strains suitable for the practical production of PUFAs.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.1
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• pp.1-9
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• 2020

ABL (Airborne Bathymetric LiDAR) is an advanced survey technology that uses green lasers to simultaneously measure the water depths and oceanic topography in coastal and river areas. Seabed point cloud extraction is an essential prerequisite to further utilizing the ABL data for various geographic data processing and applications. Conventional seabed detection approaches often use return waveforms. However, their limited accessibility often limits the broad use of the bathymetric LiDAR (Light Detection And Ranging) data. Further, it is often questioned if the waveform-based seabed extraction is reliable enough to extract seabed. Therefore, there is a high demand to extract seabed from the point cloud using other sources of information, such as geometric information. This study aimed to assess the feasibility of a ground filtering method to seabed extraction from geo-referenced point cloud data by using CSF (Cloth Simulation Filtering) method. We conducted a preliminary experiment with the RIGEL VQ 880 bathymetric data, and the results show that the CSF algorithm can be effectively applied to the seabed point segmentation.

• Applied Biological Chemistry
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• v.19 no.2
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• pp.99-103
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• 1976

The experiment was tested with fruits of eight varieties which were produced in Kyung Pook and Kyung Nam District and was carried out to investigate the changes of sobuble tannin content, hardness and sugar content during the removal of astringency, and, further more, the changes of quality after the removal of astringency. The results were as follows: 1. Soluble tannin content of Sagoksi was most in eight varieties and than was Euisung-Bansi and Chungdo-Bansi in that order. The time required of the removal of astringency tools 2.5 days in Dansungsi, 4.5days in Sagoksi. 2. Hardness was the firmest in Sagoksi and Chungdo-Bansi and it was gradually decreased as the harvest time of fruits was delayed. 3. In content of sugar, Gojongsi was most amount and Sagoksi was least amount in all varieties. Changes of sugar content showed a gradual decrease during the removal of astringency. 4. Quality of fruit after the removal of astringency was of a very superior quality in Chungdo-Bansi, Sagoksi and Euisung-Bansi.

• Food Science and Preservation
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• v.20 no.3
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• pp.296-303
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• 2013

This study was conducted to assess the possibility of preserving frozen vegetables (Aster scaber, soybean sprouts, Chinese cabbage, green pumpkin, and Welsh onion) for a long period and of using them after such storage by measuring changes in quality due to their preservation. Various freshly harvested vegetables were blanched under optimal conditions (that were determined in a preliminary experiment), quick-frozen at $-40^{\circ}C$ for 24 h, and stored at $-20^{\circ}C$. The change in the chromaticity of the frozen A. scaber, soybean sprouts, Chinese cabbage, green pumpkin, and Welsh onion did not vary. The hardness of the frozen A. scaber, green pumpkin, Chinese cabbage and Welsh onion did not change during the preservation period, whereas the hardness of the cotyledon and hypocotyl of the soybean sprouts significantly increased on the sixth month of their storage. The total bacterial counts of the A. scaber during the preservation period remained constant at $10^3$ CFU/g, whereas those of soybean sprouts, Chinese cabbage, green pumpkin, and Welsh onion decreased slightly to $10^2$ CFU/g. Coliform was not detected in any of the samples. The sensory evaluation showed that the preservation period that was used in this study did not significantly affect the marketability of the frozen vegetables. Therefore, it was considered that A. scaber, soybean sprouts, Chinese cabbage, green pumpkin, and Welsh onion can be safely preserved by freeze-storing them for up to 12 months.

• Food Science of Animal Resources
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• v.34 no.3
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• pp.387-394
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• 2014

This study was conducted to determine the effect of duck feet gelatin concentration on the physicochemical, textural and sensory properties of duck meat jellies. Duck feet gelatin was prepared with acidic swelling and hot water extraction. In this study, four duck meat jellies were formulated with 3, 4, 5, and 6% duck feet gelatin, respectively. In the preliminary experiment, the increase in duck feet gelatin ranged from 5 to 20%, resulting in a significant (p<0.001) increase in the color score, but a decline in the hardness and dispersibility satisfaction scores. An increase in the added amount of duck feet gelatin contributed to decreased lightness and increased protein content in duck meat jellies. Regarding the textural properties, increase in the added amount of duck feet gelatin highly correlated with the hardness in the center (p<0.01, $R^2=0.91$), and edge (p<0.01, $R^2=0.89$), of duck meat jellies. Meanwhile, the increase in duck feet gelatin decreased the score for textural satisfaction; duck meat jellies containing 6% duck feet gelatin had a significantly lower textural satisfaction score, than those containing 3% duck feet gelatin (p<0.05). Furthermore, a significant difference in the overall acceptance of duck meat jellies formulated with 5% duck feet gelatin was observed, as compared to those prepared with 3% duck feet gelatin. Therefore, this study suggested that duck feet gelatin is a useful ingredient for manufacturing cold-cut meat products. In consideration of the sensory acceptance, the optimal level of duck feet gelatin in duck meat jellies was determined to be 5%.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.1
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• pp.12-19
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• 1999

CERES-rice, a rice growth simulation model, was used in conjunction with daily weather data to figure out the spatial variation of the phenology and yields of paddy rice at 168 rice cultivation zone units(CZU) of Kyunggi Province in 1997. Two sets of cultivar specific coefficients, which represent early and mid-season maturing varieties, were derived from field experiments conducted at two crop experiment stations. The minimum data set to run the model for each CZU (daily maximum and minimum temperature, solar irradiance, and rainfall) was obtained by spatial averaging of existing 'Digital Map of Korean Climate'(Shin et al., 1999). Soil characteristics and management information at each CZU were available from the Rural Development Administration. According to a preliminary test using 5 to 9 years field data, trends of the phasic development(heading and physiological maturity), which were obtained from the model adjusted for these coefficients, were in good agreement with the observed data. However, the simulated inter-annual variation was somewhat greater than the reported variation. Rough rice yields of the early maturing cultivar calculated by the model were comparable with the reported data in terms of both absolute value and inter -annual variation. But those of the mid season cultivar showed overestimation. After running the simulation model runs with 1997 weather data for 168 CZU's, rough rice yields of the 168 CZU's calculated by the model were aggregated into corresponding 33 counties by acreage-weighting to facilitate direct comparison with the reported statistics from the Ministry of Agriculture and Forestry. The simulation results were good at 22 out of the 26 counties with reportedly increasing yield trend with respect to the past 9 years average.

• Journal of Periodontal and Implant Science
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• v.38 no.1
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• pp.59-66
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• 2008

Purpose: It has been shown that the inorganic polyphosphate is effective for the regeneration of bones through the preliminary animal test of rabbits. The most effective concentration of the polyphosphate, however, is not known yet. Moreover, the effectiveness of carriers inside human body is not confirmed.. Materials and Methods: In this study, we examined the effect of the concentration of the inorganic polyphosphate on the process of the bone regeneration using the 6 weeks old rabbits with the weight of 2.0 kg in average. We performed the experiment using TR-ePTFE membrane(membrane) filled with collagen immersed in 4%, 8% of inorganic polyphosphate, respectively, following removal of the proper sized cortical bones from the rabbit calvaria. The experimental results were compared with the one of the following four groups: The negative control group for membrane only, the positive control group for membrane filled with collagen, the first experimental group for membrane filled with collagen immersed in 4% of inorganic polyphosphate, and the second experimental group for membrane filled with collagen immerse in 8% of inorganic polyphosphate. The fragments of the tissue with membrane obtained from each group of the sacrificed rabbits for 8 or 16 weeks sustained after surgery were then prestained by the Hematoxylin-Eosin stain and coated by resin to form non-decalcified specimens for the histologic examination and analysis. New bone formation was assessed by histomorphometric and statistical analysis. Results: 1. All groups have shown better bone regeneration at 16weeks than 8weeks. 2. Negative control group has shown more bone regeneration relative to the other groups at 8 and 16 weeks. 3. All experimental groups have shown better bone regeneration relative to positive control group. 4. At 16 weeks, the first experimental group has shown more bone regeneration compared to the second experimental group. Exophytic bone formation is not good at the first and the second experimental groups compared with negative control group. But, the use of 4% inorganic polyphosphate was more effective to bone formation than the use of 8% inorganic polyphosphate. Conclusion: With above results, it is suggested the use of inorganic polyphosphate with vehicle under TR-ePTFE membrane.

• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.81-97
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• 1987

Two nozzles with different size (Figure 2) were particularly designed to supply air through the swirl core into the central part of the liquid stream in the same parallel direction to produce a well-mixed air and water in the whirl chamber as spray liquid in bubble formation. Atomization was attempted to improve by using both the preliminary break-up process with less viscosity and less surface tension in the whirl chamber and the effects of increased frequency of the band of drops with the raised ambient air density in front of the nozzle orifice. The volumetric ratio between spray liquid and air on four levels was used to investigate the effects of air as a component of the mixture on atomization. The results of the experiment were summarized as follows; Droplet size became progressively finer as the operating pressure was increased in the range of $0.70kg/cm^2$ to $6.33kg/cm^2$, which was similar to the previous works. The new atomizing mechanism so-called 'air-center nozzle' gave a narrower range in droplet size distribution with smaller volumetric median diameter (VMD) than that of the existing spray system at a given pressure, which showed the possibility of improvement of atomization in a certain limit. The volumetric median diameter produced by the new atomizing mechanism was decreased from the central region toward the exterior edges across the spray pattern.

• Korean Journal of Agricultural Science
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• v.28 no.2
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• pp.70-77
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• 2001

A preliminary experiment was conducted to produce fowl-typhoid resistant egg type breeds, using three brown egg layer breeders (ISA, Hyline, and Lohman) and two white egg layer breeders (ISA and Lohman). Various economic parameters were measured from day-old to mature stages using parent stocks of each breed. No significant difference in viabilities of mature hens from 34 to 66 wk of ages was found between brown(93.3%) and white(93.5%) egg layer breeders (P>0.05). Also, there was no difference in viabilities of mature cockerels. Although not significant, the mature body weights of brown egg layer breeders tended to be heavier than those of the white egg layer breeders both in hens and cockerels. No difference in feed intakes of mature brown and white hens were detected. Ages of sexual maturity of white and brown egg layer hens were 147.7 and 140.5 d, respectively (P<0.05). Egg production of white egg layer hens during 23-66 weeks age was significantly higher than their counterpart (81.4% vs. 75.0%). Comparisons of Haugh Unit, egg shape index, yolk color, and egg weight between brown and white eggs were not significantly different; however, the brown eggshells were thicker and stronger than those of white eggs (P<0.05).