• Economic and Environmental Geology
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• v.53 no.1
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• pp.23-32
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• 2020

Geological CO₂ sequestration is a global warming response technology to limit atmospheric emissions by injecting CO₂ captured on a large scale into deep geological formations. The presented results concern mineralogical and hydrogeological investigations (FE-SEM, XRD, XRF, and MICP) of mudstone samples from drilling cores of the Pohang basin, which is the research area for the first demonstration-scale CO₂ storage project in Korea. They aim to identify the mineral properties of the mudstone constituting the caprock and to quantitatively evaluate the hydrogeologic sealing capacity that directly affects the stability and reliability of geological CO₂ storage. Mineralogical analysis showed that the mudstone samples are mainly composed of quartz, K-feldspar, plagioclase and a small amount of pyrite, calcite, clay minerals, etc. Mercury intrusion capillary pressure analysis also showed that the samples generally had uniform particle configurations and pore distribution and there was no distinct correlation between the estimated porosity and air permeability. The allowable CO₂ column heights based on the estimated pore-entry pressures and breakthrough pressures were found to be significantly higher than the thickness of the targeting CO₂ injection layer. These results showed that the mudstone layers in the Yeongil group, Pohang basin, Korea have sufficient sealing capacity to suppress the leakage of CO₂ injected during the demonstration-scale CO₂ storage project. It should be noticed, however, that the applicability of results and analyses in this study is limited by the lack of available samples. For rigorous assessment of the sealing efficiency for geological CO₂ storage operations, significant efforts on collection and multi-aspect evaluation for core samples over entire caprock formations should be accompanied.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.448-453
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• 2014

Influences of shading and irrigation in summer hot pepper cultivation on the plant growth and mesophyll tissue were investigated. Hot pepper plants were exposed to three shade levels (0, $30{\pm}5$ and $80{\pm}5%$) and irrigated or non-irrigated in greenhouse condition. Plant height and leaf area were highest in 30% shading and stem diameter and fresh and dry weights were highest in no shading. Plant growth was better in rain shelters with irrigation than in those without irrigation. The numbers of hot pepper fruits in the beginning of harvest were 49 in rain shelters without irrigation and shading, 22 in those with irrigation and without shading, 5 in those without irrigation with 30% shading, and 1 in those with irrigation and 30% shading. However, 80% shading showed lowest flower number and flower abscission, resulting in no fruit set, regardless of irritation. This is because carbohydrate translocation from leaves to reproductive organs may be not enough for developing fruits due to the lack of sunlight. The yield of hot pepper tended to be higher in rain shelter with irrigation than in those without irrigation. In optical microscopy observation, the thickness and development of mesophyll tissues decreased as increasing the degree of shading but no effect of irrigation on mesophyll tissues was observed. When stomata were observed with scanning electron microscope (SEM), the shape of stomata was normal but tissues surrounding stomata were slightly wrinkled in plants grown under 30% shading. The large number of abnormal stomata and wrinkled leaves was observed among plants grown in rain shelters with 80% shading. In plants grown in rain shelters without irrigation, tissues surrounding stomata were wrinkled and 10-20% decrease in the number of stomata was observed. Therefore, in hot pepper cultivation in summer with high temperature, shading was not effective for fruit yield and mesophyll tissue development; if shading is unavoidable, high degree of shading is not advisable. Further studies are needed for appropriate cultivar selection and environment-control techniques in hot pepper cultivation in summer with high temperature.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.490-495
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• 2013

Two chrysanthemum varieties, 'ARTI-purple' and 'ARTI-queen', were chronically irradiated with doses of 30, 50, 70, and 100 Gy for four weeks in gamma-phytotron, a long term irradiation facility. We investigated the growth, responses of antioxidant enzymes (ascorbate peroxidase, APX; catalase, CAT; peroxidase, POD; superoxidase dismutase, SOD) and malondialdehyde (MDA) contents under different doses of chronic-irradiation. The five plant growth measurements including plant height, number of leaves, internode length, stalk diameter and leaf thickness were investigated immediately after four week irradiation. The plant height (p<0.001), internode length (p<0.01), the number of leaves (p<0.001) and stalk diameter (p<0.05) were significantly decreased an increasing doses of gamma-ray. Among them, especially, the internode length was remarkably decreased showing the RD50 (Reduction Dose 50) at approximately 65 Gy. The antioxidant response after four weeks of recovery period, ascorbate peroxidase (APX) (p<0.01), superoxide dismutase (SOD) (p<0.01) and peroxidase (POD) (p<0.001) were significantly increased with an increasing dose of gamma-ray. And malondialdehyde (MDA) (p<0.01) contents showed the significant increase at the 70 and 100 Gy which means the oxidative stress was lasting for a considerable period. In this study, the 50 Gy irradiation as optimal dose showed higher growth than the $RD_{50}$, it also showed insignificant differences on the antioxidant responses and MDA contents. However, the 100 Gy dose showed lower growth than $RD_{50}$.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.407-414
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• 2013

This study was carried out to understand the physiological characteristics of 'Manpungbae' (Pyrus pyrifolia Nakai) pears through the seasonal changes of pericarp structure and anatomical differences between bagging and non-bagging treatment, and also fruit quality and peel coloration characteristics at the harvest time. The pericarp at full bloom was consists of outer epidermis, hypodermis, parenchyma cell, and inner epidermis from the exterior. The cell layers from the outer epidermis to vascular bundle increased rapidly 7-10 layers to 18-26 layers from full bloom (FB) to 77 days after full bloom (DAFB) and did not change significantly until maturity. Thus, the cell division period of 'Manpungbae' pear was until 77 DAFB and during this period, the thickness from hypodermis to vascular bundle increased from $73.1{\mu}m$ to $195{\mu}m$ in this period. Stone cells were formed from seven to 21 DAFB and stone cell clusters were formed around 49 DAFB. The cork cell layer was formed between 49 and 77 DAFB. 'Manpungbae' fruit pericarp was consists of 4.5 layers of the cork cell layers and seven layers of hypodermis which has the tannin at harvest time (161 DAFB). Comparison of the fruit enlargement and fruit structure development by bagging or non-bagging showed that 'Manpungbae' fruits without bagging had more than three cork cell layer than those with bagging at maturity. The size of stone cell clusters were varied in two treatments. Fruit weight was higher in the non-bagging treatment but there was no difference in soluble solid contents (SSC) between two treatments. The weight of the 'Manpunbae' fruit was distributed from 301 g to more 900 g and the average fruit weight was 677.2 g at harvest time, and fruits in the range of 551-800 g accounted for 71.6% of total production. The SSC, acidity and SSC/acidity ratio was $10.2-12.1^{\circ}Brix$, 0.10-1.24% and 9.76-14.31 respectively, and the SSC was higher in bigger fruit which had a very higher positive correlation with a fruit weight. However, the fruit firmness tended to be lower with fruit size which had a very higher negative correlation with the fruit weight and SSC. The cork cell layer numbers between yellowish brown and green pericarp were not different significantly, in 3.8 and 3.5 respectively.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.149-157
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• 2003

This study focused on relationships between Pb and Cd concentrations and the difference of success reproductive progress in urban (Seoul) and industrial complex (Ansan) areas. Results of the Pb analysis for the feral pigeons from Seoul (egg contents:1.64 $\mu\textrm{g}$ wet $g^{-1}$, adults in bones: 29.5 $\mu\textrm{g}$ wet $g^{-1}$ and the Ansan industrial complex (egg contents: 1.13 $\mu\textrm{g}$ wet $g^{-1}$, adults in bones: 10.5 $\mu\textrm{g}$ wet g-1) showed that the Pb level of eggs and adults is significantly different between the two colonies (p<0.05). Cd concentrations in liver and kidneys of adult pigeons were also significantly different between Seoul(liver: 0.24 ${\mu}g$ wet $g^{-1}$, kidney: 1.05 $\mu\textrm{g}$ wet $g^{-1}$ and the Ansan (liver: 0.14 $\mu\textrm{g}$ wet $g^{-1}$, kidney: 0.43 $\mu\textrm{g}$ wet $g^{-1}$ colonies (P<0.05). Clutch size of Feral Pigeons living in Seoul was similar between the two colonies, 1.9$\pm$0.3 in Seoul and 2.0$\pm$0.0 in Ansan. The length, breadth, and thickness of eggs were not significantly different between the two colonies (p>0.05). Incubation period in Seoul (17.8 days) did not differ from the Ansan (17.4 days). No difference in growth rate (body weight, wing length, and tarsus length) was found between the two test groups (p>0.05). In Seoul, 65.2% were hatching, and 42.1% fledging. The Proportion of hatching and fledging in the Ansan was 60.7% and 45.0%, respectively. The significant differences between the two colonies for reproductive sucess were not found (p>0.05). With regard to the reproductive effects to the heavy metals, the Pb and Cd concentrations feund in the two colonies were not as high as those considered in results of toxic effects in other species.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.103-109
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• 2016

Polyethylene pipes has useful benefits which are anti-corrosive and flexible material, so it is used to gas pipes but also class 3 water pipes of nuclear power plant, process pipes of petrochemical plant and chemical plant. So the usage of polyethylene pipes is widely increased. But it has been limited for the usage of polyethylene, because it can not be directly detected to fusion joints by using non destructive evaluation. Polyethylene pipes are connected by two methods, one is butt fusion and the other is electrofusion. Butt fusion is widely used to connecting the pipes. It is proposed to method for determining the reliability of joints in this study that is detection of the melt flow zone at fusion joints. In this study, middle density polyethylene is used, outside diameter of the test specimen is 225mm and thickness is 20.5mm. Speed of ultrasonic of this test specimen is 2,200m/s. Test specimens were fabricated by varying the heating time which means from 0% to 130% applying time through heating plate to polyethylene for detecting melt flow zone. Also 4 additional test specimens were made, one was made that not scrapping attached surface of pipes but applying 100% of the proper heating time and the others were made to include of soil, gravel and vinly tape paper at fusion joints, that were also applied 100% of proper heating time. Ultrasonic testing to measure the melt flow zone of 20 test specimens was conducted by using 3.5MHz and 5.0MHz ultrasonic probes and melt flow zone measuring was conducted to three times at different point to one specimen. To differentiate the melt flow zone signal, post image processing was equally conducted to all test results and image levels, contrast, sharpen, threshold were adopted to all teat results and the test results were displayed gray scale. From the results, for the shorter heating times the reflection area of multiple echo have been increased, so the data was obtained from the position where it can be eliminated as much as possible. At 80% of proper heating time(168 sec.), the signal of melt flow zone was obtained clearly, so measuring could be conducted. From 7% of proper heating time(15 sec.) to shorter heating times. we could not obtain the signal because test specimen was not fused. From the result, we can verify that measuring of melt flow zone by using phased array ultrasonic imaging method is possible. And we can verify to complete and incomplete butt fusion by measuring the melt flow zone.

• Ecology and Resilient Infrastructure
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• v.7 no.3
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• pp.208-217
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• 2020

A biopolymer based on microorganism-derived β-glucan and xanthan gum is being studied as a new eco-friendly material that stabilizes the riverbank slope, and also promotes vegetation growth. However, it is still inconclusive whether biopolymers have a positive effect on plant performance in the riverbanks which are subjected to various climatic factors and plant competitions. For a practical ecological evaluation of the biopolymers, their effect on plant growth promotion was studied in a natural environment. Considering the relationship between competition and plant community formation, the effects of biopolymers on competition were also investigated. For four plant species (Echinochloa crus-galli, Pennisetum alopecuroides, Leonurus japonicus, and Coreopsis lanceolata), the biopolymer effects under intra/interspecific competition were tested at the riverbank (20 m × 10 m) near Samjigyo Bridge in Damyang-gun, Jeollanam-do. A biopolymer powder was mixed with water and commercial soil following the manufacturer's recommendations. The soil mixed with the biopolymer was filled in a pot or applied to the surface of the commercial soil with a thickness of 3 cm. Across the competition treatments, the biopolymer treatment promoted root growth of the target plant species and decreased the specific leaf area. The total biomass and shoot dry weight of P. alopecuroides increased in response to the biopolymer treatment. The competition treatment decreased the total biomass and shoot dry weight compared to the case without competition. Notably, such a competitive effect was similar in all the biopolymer treatments. Thus, biopolymers, when mixed with soil, promote the growth of some plant species, but do not appear to affect the competitive ability of plants.

• Korean Journal of Poultry Science
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• v.18 no.1
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• pp.33-42
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• 1991

In order to study effects of the 9round charcoal and organic acid on the egg production, White Leghorn strain(Hyline) layer of 113 week-old were fed control diet during a week of previous feeding and subsquent experimental diets during 12 weeks of experimental feeding . The experimental diets were the basal (control) diet composed of mainly corn-soybean meal, diet (CPB) substituted 0.5％ of ground charcoal with the defatted rice bran of the control, diet (PWV) added 0.1 mM(based on the acetic acid) of wood vinegar in the CPD and diet(PFA) added 0.1 mM (based on the acetic acid) of fermented acetic acid in the CPD. During experimental feeding period, birds (ed control, CPD and PWV diets showed similar feed intake which was shown a decreasing tendency in birds fed PFA diet as the passage of experimental feeding period. Birds fed experimental diets containing ground charcoal were tended to increase egg weight (g/egg) , while which of birds fed CPD was higher(P＜0.05) than that fed control diet. Chicks fed the control, CPD and PWV diets produced 75.9, 75.0 and 75. 9％ of egg, respectively, which were significantly(P＜0.05) higher than those of birds fed PFA. Daily egg mass(g/bird) were reached to 48.6, 49.9 and 49.5g i,1 layer fed the control, CPD and PWV diets, respectively, showing an increasing tendency in layer fed CPD and PWV compared with those of birds fed control, which were significantly (P＜0.05) higher than those of birds fed PFA . Although the effect of experimental diets on the feed efficiency (egg/feed) was not found, which was shown an increasing tendency in layer fed CPD compared with those in control diet. Compared with the incidence of cracked or shelless eggs in birds fed control diet, which were lowered to 37％ in birds fed CPD diet and 70％ in PWV-fed birds and increased to two times in birds fed PFA . The contents of cholesterol in egg was not affected by experimental diets, while birds fed CPD diet increased significantly(P＜0.05) the daily biosynthesis of egg protein and showed a trend to increase the thickness of eggshell and eggshell contents per eggs compared with that of control diet-fed birds. The results indicated that the ground charcoal powder improved the performance of layer.

• Korean Journal of Poultry Science
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• v.30 no.1
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• pp.1-10
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• 2003

The objects of this study were to develop a new strain which has resistance to fowl typhoid, high performance in laying, and producing brown shell eggs favored by domestic consumers. Several White Leghorn (WL) breeds known as possessing genetic resistance to fowl typhoid and several brown shell egg breeds such as susceptible to the disease were used to produce the controlled strains with cross mating between the strains within the breeds and the experimental strains with crossbreeding between the breeds. The crossbred strains were Chungnong(CN) 21, 22, 23, 24, 25 and 26. The controlled strains were ISA brown CC, Hyline brown CC and Lohman brown CC. The survival rates were 99.95% for chicks of age 0∼l7 weeks and 91% for adult chickens of age 18∼72 weeks. There was no difference in survival rate between the crossbred and the controlled strains. The means of age of lst egg laying were 147 to 148 days and no difference was observed between the crossbred and the controlled. The egg Production rates of a9e 18∼72 weeks were 83.76% far the crossbred strains and 77.82% for the controlled strains, which is significantly higher in the crossbred than controlled strains by 6%. The numbers of the hen housed egg Production of age 18∼72 weeks were 292.33 eggs for the crossbred strains and 271.31 eggs fur the controlled strains. The difference of 21 eggs more produced by the crossbred than by the controlled was statistically significant. The mean egg weights of age 18∼72 weeks were 64.32g for the crossbred strains and 60.73g for the controlled strains, and the difference of 3.59g was statistically significant. The feed conversion rates during the age of 18 to 72 weeks were 2.297 for the crossbred strains and 2.454 for the controlled strains. The crossbreds were reduced feed consumption by 157g for 1kg of egg Production which was statistically significant. Haugh unit(H$.$u) at the age of 72 weeks were 82.20 for the crossbred strains and 77.82 for the controlled strains. The crossbred strains were superior quality by 4.38 H$.$u. There were no significant differences in the yolk color and the eggshell thickness between the crossbred strains and the controlled strains. The eggshell color of the crossbred strains was light brown which is the medium color of the white eggshell strains and the brown eggshell strains. The body weights at the ages of 8, 12, 18, 42 and 71 weeks were not different between the crossbred strains and the controlled strains.

• Korean Journal of Poultry Science
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• v.21 no.1
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• pp.1-19
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• 1994

This study was carried out to investigate the effects of shperical surface of eggs tray and eggshell on breaking strength of eggs for the development of a new egg tray design to prevent eggshell breakage. The results obtained were as follows: 1. According to the results obtained from investigation on the types of 22 egg trays collected from 9 countries(USA, Italy, France, Thailand, Japan, Netherland, Russia, Korea and Swiss), all egg trays except those from Korea were different in their types. 2. According to the determination of breaking strength for 4 pilot egg trays, type B and D were high in breaking strength. Trays B and D which would fit with the spherical surface of egg so that they could increase breaking strength were most recommendable. Breaking strength was not increased even though egg tray was strong. Thickness of eggshell of experimental eggs used in this experiment have no significance (P>0.05). 3. When eggs are packed and transported in egg tray, the breaking strength will depend on how much spherical surface of egg are covered by the spherical surface of the egg tray. Therefore, the inner spherical surface of egg tray must fit to the outer spherical surface of eggs when the egg tray is manufactured. 4. At present, there is only one type of egg tray being used in Korea despite the various egg sizes. In order to minimize the eggshell breakage, however, proper sizes or types of egg trays should be developed for each different categories of the egg size.