• Food Science and Preservation
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• v.18 no.3
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• pp.288-293
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• 2011

This study investigated the changes in the quality of fresh-cut lotus roots that were treated with hot water. Lotus roots were purchased from Daegu, Korea. They were washed, peeled, and cut into lcm-thick slices with a ceramic knife. The peeled and sliced lotus roots were dipped for 45 sec in water at 30, 55, and $80^{\circ}C$. After they were air-dried at room temperature, the slices were packed in polyethylene films and stored at $4^{\circ}C$ for 12 d. Then the changes in the weight loss, color, total viable cell, and sensory characteristics were measured. Generally, the weight loss of the lotus roots that were treated with hot water slightly increased. The application of the heat treatment delayed the browning of the lotus roots, especially the treatment with $55^{\circ}C$ hot water. The L and a values of the lotus roots that were treated with $80^{\circ}C$ hot water significantly increased during their storage, though. The heat treatment effectively inhibited the growth of microorganisms. The organoleptic quality of the lotus roots that were treated with $55^{\circ}C$ hot water was the best.

• Journal of Forest and Environmental Science
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• v.34 no.6
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• pp.461-471
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• 2018

In this study, the deforestation and forest degradation areas have been obtained in Myanmar using a land cover lamp (LCM) and a tree cover map (TCM) to get the $CO_2$ potential reduction and the strength of occurrence was evaluated by using the geostatistical technique. By applying a multiple criteria decision-making method to the regions having high strength of occurrence for the $CO_2$ potential reduction for the deforestation and forest degradation areas, the priority was selected for candidate lands for REDD+ project. The areas of deforestation and forest degradation were 609,690ha and 43,515ha each from 2010 to 2015. By township, Mong Kung had the highest among the area of deforestation with 3,069ha while Thlangtlang had the highest in the area of forest degradation with 9,213 ha. The number of $CO_2$ potential reduction hotspot areas among the deforestation areas was 15, taking up the $CO_2$ potential reduction of 192,000 ton in average, which is 6 times higher than that of all target areas. Especially, the township of Hsipaw inside the Shan region had a $CO_2$ potential reduction of about 772,000 tons, the largest reduction potential among the hotpot areas. There were many $CO_2$ potential reduction hot spot areas among the forest degradation area in the eastern part of the target region and has the $CO_2$ potential reduction of 1,164,000 tons, which was 27 times higher than that of the total area. AHP importance analysis showed that the topographic characteristic was 0.41 (0.40 for height from surface, 0.29 for the slope and 0.31 for the distance from water area) while the geographical characteristic was 0.59 (0.56 for the distance from road, 0.56 for the distance from settlement area and 0.19 for the distance from Capital). Yawunghwe, Kalaw, and Hsi Hseng were selected as the preferred locations for the REDD+ candidate region for the deforestation area while Einme, Tiddim, and Falam were selected as the preferred locations for the forest degradation area.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.1
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• pp.1-12
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• 2021

In the design of a tunnel boring machine (TBM), the excavation efficiency of the equipment depends on the design of the cutter head, which is directly in contact with the ground. Especially, the allocation of disc cutter is crucial issue. Disc cutters can be divided into center cutter zone, inner cutter zone and transition cutter zone depending on where they are placed. Many studies have been conducted to identify optimal cutting conditions for face cutters. However, research to determine the optimal cutting conditions for the transition cutter has been relatively incomplete. In this study, to identify the optimal cutting conditions for the transition cutter, numerical analysis using discrete element method was performed, and the specific energy curve according to the angle between the transition cutters was drawn to find out the optimum cutting conditions. The results show that the angle between the transition cutters showing minimum specific energy in the transition cutter zone is 9°. Transition cutter zone was divided into three sections according to the slope angle of the transition cutter. It is also found that, the greater the slope angle of the transition cutter. This finding shows good agreement with the present design of transition cutter zone.

• Korean Journal of Environmental Biology
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• v.18 no.2
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• pp.279-290
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• 2000

To alleviate the harmful effects from contamination, the Sihwa Lake waters have been regularly fluxed out into the ocean to mix and circulate with the oceanic waters, and then allowed to flow back into the lake. In the present study, eco-environmental impacts by the outflowing contaminated lake waters to the benthic communities of the coastal zones along Kyonggi Bay were examined at three separate areas. A total of 22 groups of meiobenthic animals were commonly found in the subtidal zones of the Bay. All groups of the meiobenthic animals on the 1st and 7th days after the outflow were remarkably reduced in numbers from the selected areas examined, as compared to those observed one day before the outflow. It was also found that the community structure of meiobenthos was changed drastically: At the station near the water gate, for example, where the immediate outflow of the lake water was encountered, the benthic harpacticoids, the group observed to be one of the predominant groups before the outflow, were found to have disappeared completely. For an area that was relatively far away from the water gate, the reduction rate of meiobenthos after the outflow events was slower and more gradual than the nearer sites. An area that is the farthest from the water gate, no reduction in any of the meiobenthos group was observed. The ratio between nematodes/copepods (N/C) was remarkably changed by the outflows at the station near the water gate: One day before the outflow, the ratio was 0.7 while the ratio was 19.0 at the station near the water gate. In contrast, at the stations relatively far from the water gate, the ratio decreased one day after the outflow event, but increasing trends were observed one week later. In the tidal flats, Station 1 exhibited the common observed regional values of the ratio whereas Station 2 showed a very high ratio of 191.3. The results suggested that the contaminated lake water outflows directly effect meiobenthos in a relatively short time period and thus the meiobenthos may be a good indicator animal group for examining the effect of pollution. [Lake Sihwa, contaminat water outflow, meiobenthic animals living]

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.671-683
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• 1995

This study was aimed to provide understanding on the eco-physiological response of barley tillers as affected by sowing depth. Yield and yield contribution rate of tillers were investigated with the data of field experiments in the former Wheat and Barley Research Institute of Suwon, Korea from October 1983 to July 1984. When barley was sowed in various depth of 1, 3, 5, 7 and 9cm below the ground surface, 13 mainstem leaves appeared by 3 and 5cm treatments, and 11 leaves by 1, 7 and 9cm treatments. The effective tillers were observed from 8/0 in lcm depth, while 10/0 in 3-5cm depth and 9/0 in 7cm depth. There was no coleoptile tiller in 7cm depth sowing. Deep and shallow sowings produced fewer leaves and tillers, as early growth was hindered by deep sowing whereas cold damage was apparent in shallow sowing. Accordingly, more effective tillers per plant and higher grain weight per ear were observed in 3∼5cm depth sowing. Yield contribution by the tillers with various sowing depth was as follows: mainstem, 1, 2, 11, 3, 21, 4 and 12. The contribution of 1P, 13, 2P, 23 and 31 varied with the treatments.

• Korean Journal of Weed Science
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• v.18 no.3
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• pp.205-213
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• 1998

This experiment was carried out to produce herbicide resistant potatoes hawing only chimeric phosphinothricin acetyltransferase (PAT) genes without using antibiotic selectable marker. The pDY502 vector having only PAT gene was reconstructed for transformation of potato. The reconstructed vector was introduced to Agrobacterium tumefaciens MP90 disarmed, and they were used for potato transformation. Hormonal requirement for plant regeneration from leaves and stem explants of potato was investigated. From this experiment, MS medium treated with IBA 0.1 mg/L + BA 0.5 mg/L was the best for potato regeneration, and the ratio of shoot regeneration was 54% for leaf and 46% for stem in that condition. For transformation, explants of potato leaves and stems were cocultured with A. tumefaciens MP90 containing reconstructed vector harvoring only PAT gene. When the potato explants were placed on various concentrations of bialaphos and all the potato explants were dead on medium with over 5.0mg/L bialaphos. By this selection methods, the explants cocultured with Agrobacterium produced the putative transgenic shoots on medium with 5mg/L bialaphos treatment after 3-4 weeks. Second selection was performed by transferring the shoot tips of putative transgenic to medium containing 20mg/L of bialaphos. The shoot tips grew well on the second selection medium, indicating the production of successful transgenic plants. But normal shoots were dead in same cytotoxic medium. Incorporation of the PAT gene into transgenic potatos were confirmed by PCR analysis of DNA and Southern hybridization. These results show that the PAT gene can serve as a selectable marker and herbicide resistant genes for transformation of potato.

• Progress in Medical Physics
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• v.9 no.2
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• pp.65-71
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• 1998

The aims are to evaluate the effects of an 1.0 cm acrylic plate and SSD on the dose profile and depth dose distribution of 9 MeV electron beam and to analyse adequacy for using an acrylic plate to reduce energy of electron beams. An acrylic plate of 1.0 cm thickness was used to reduce energy of 9 MeV electron beam to 7 MeV. The plate was put on an electron applicator at 65.4 cm distance from x-ray target. The size of the applicator was 10${\times}$l0cm at 100 cm SSD. For 100cm, l05cm and 110cm SSD, depth dose on beam axis and dose profiles at d$\_$max/ on two principal axes were measured using a 3D water phantom. From depth dose distributions, d$\_$max/, d$\_$85/, d$\_$50/ and R$\_$p/, surface dose, and mean energy and peak energy at surface were compared. From dose profiles flatness, penumbra width and actual field size were compared. For comparison, 9 MeV electron beams were measured. Surface dose of 7 MeV electron beams was changed from 85.5% to 82.2% increasing SSD from 100 cm to 110 cm, and except for dose buildup region, depth dose distributions were independent of SSD. Flatness of 7 MeV ranged from 4.7% to 10.4% increasing SSD, comparing 1.4% to 3.5% for 9 MeV. Penumbra width of 7 MeV ranged from 1.52 cm to 3.03 cm, comparing 1.14 cm to 1.63 cm for 9 MeV. Actual field size increased from 10.75 cm to 12.85 cm with SSD, comparing 10.32 cm to 11.46 cm for 9 MeV. Virtual SSD's of 7 and 9 MeV were respectively 49.8 cm and 88.5cm. In using energy reducer in electron therapy, depth dose distribution were independent of SSD except for buildup region as well as open field. In case of using energy reducer, increasing SSD made flatness to deteriorate more severely, penumbra width more wide, field size to increase more rapidly and virtual SSD more short comparing with original electron beam. In conclusion, it is desirable to use no energy reducer for electron beam, especially for long SSD.

• Journal of Sericultural and Entomological Science
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• v.8
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• pp.11-25
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• 1968

Various formulae for estimation of leaf production in mulberry trees were investigated and obtained. Four varieties of mulberry trees were used as the materials, and seven characters namely branch length. branch diameter, node number per branch, total branch weight, branch weight except leaves, leaf weight and leaf area, were studied. The formulae to estimate the leaf yield of mulberry trees are as follows: 1. Varietal differences were appeared in means, variances, standard devitations and standard errors of seven characters studied as shown in table 1. 2. Y$_1$=a$_1$X$_1$${\times}$P$_1$......(l) where Y$_1$ means yield per l0a by branch number and leaf weight determination. a$_1$.........leaf weight per branch. X$_1$.......branch number per plant. P$_1$........plant number per l0a. 3. Y$_2$=(a$_2$${\pm}$S. E.${\times}$X$_2$)+P$_1$.......(2) where Y$_2$ means leaf yield per l0a by branch length and leaf weight determination. a$_2$......leaf weight per meter of branch length. S. E. ......standard error. X$_2$....total branch length per plant. P$_1$........plant number per l0a as written above. 4. Y$_3$=(a$_3$${\pm}$S. E${\times}$X$_3$)${\times}$P$_1$.....(3) where Y$_3$ means of yield per l0a by branch diameter measurement. a$_3$.......leaf weight per 1cm of branch diameter. X$_3$......total branch diameter per plant. 5. Y$_4$=(a$_4$${\pm}$S. E.${\times}$X$_4$)P$_1$......(4) where Y$_4$ means leaf yield per 10a by node number determination. a$_4$.......leaf weight per node X$_4$.....total node number per plant. 6. Y$\sub$5/= {(a$\sub$5/${\pm}$S. E.${\times}$X$_2$)Kv}${\times}$P$_1$.......(5) where Y$\sub$5/ means leaf yield per l0a by branch length and leaf area measurement. a$\sub$5/......leaf area per 1 meter of branch length. K$\sub$v/......leaf weight per 100$\textrm{cm}^2$ of leaf area. 7. Y$\sub$6/={(X$_2$$\div$a$\sub$6/${\pm}$S. E.)}${\times}$K$\sub$v/${\times}$P$_1$......(6) where Y$\sub$6/ means leaf yield estimated by leaf area and branch length measurement. a$\sub$6/......branch length per l00$\textrm{cm}^2$ of leaf area. X$_2$, K$\sub$v/ and P$_1$ are written above. 8. Y$\sub$7/= {(a$\sub$7/${\pm}$S. E. ${\times}$X$_3$)}${\times}$K$\sub$v/${\times}$P$_1$.......(7) where Y$\sub$7/ means leaf yield estimates by branch diameter and leaf area measurement. a$\sub$7/......leaf area per lcm of branch diameter. X$_3$, K$\sub$v/ and P$_1$ are written above. 9. Y$\sub$8/= {(X$_3$$\div$a$\sub$8/${\pm}$S. E.)}${\times}$K$\sub$v/${\times}$P$_1$.......(8) where Y$\sub$8/ means leaf yield estimates by leaf area branch diameter. a$\sub$8/......branch diameter per l00$\textrm{cm}^2$ of leaf area. X$_3$, K$\sub$v/, P$_1$ are written above. 10. Y$\sub$9/= {(a$\sub$9/${\pm}$S. E.${\times}$X$_4$)${\times}$K$\sub$v/}${\times}$P$_1$......(9) where Y$\sub$7/ means leaf yield estimates by node number and leaf measurement. a$\sub$9/......leaf area per node of branch. X$_4$, K$\sub$v/, P$_1$ are written above. 11. Y$\sub$10/= {(X$_4$$\div$a$\sub$10/$\div$S. E.)${\times}$K$\sub$v/}${\times}$P$_1$.......(10) where Y$\sub$10/ means leaf yield estimates by leaf area and node number determination. a$\sub$10/.....node number per l00$\textrm{cm}^2$ of leaf area. X$_4$, K$\sub$v/, P$_1$ are written above. Among many estimation methods. estimation method by the branch is the better than the methods by the measurement of node number and branch diameter. Estimation method, by branch length and leaf area determination, by formulae (6), could be the best method to determine the leaf yield of mulberry trees without destroying the leaves and without weighting the leaves of mulberry trees.