• Journal of Environmental Science International
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• v.6 no.4
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• pp.379-384
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• 1997

The biodegradable characteristics of poly-$\beta$-hydroxybutyrate(PHB) film by fun맥 and soil burial are Investigated. As the results of the American Standards for Testing and Materials(ASTM) method, the you of Aspergillus niger was apparent on the PHB containing plate. This suggests that PHB was utilized as the sole carbon source by Aspergillus niger and ASTM method may have applications as measuring means of biome gradability of polyhydroxyalkanoic acid(PHA). PHB film was studied by monitoring the time-dependant changes in weight loss of PHB film under 30% and relative humidity 80 % during pot-test. As the results of pot-test, PHB film was decomposed about 87 % in 30 days by soul microorganisms. PHB film was more slowly degraded than PHB/HV film.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.2
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• pp.95-105
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• 2022

In this study, the fishery status of the octopus pot fishery in the east coastal sea were investigated, and the fishing performance of each pot shape was compared and analyzed. The fishery status survey was conducted through listening surveys at Jukbyeon Port, Uljin Port and Pohang Daebo Port in Gyeongbuk Province, and the amount of fishing gear used, fishing method, size and loss of octopus pot fishery was investigated. On the east coastal sea, octopus is one of the commercially important fish stocks and is caught in inshore pots, inshore combos, inshore gillnets and offshore pots. Among these fishing methods, pot fishing yields the highest catch. The shape of the pot differs depending on the region. In Uljin (Jukbyeon Port and Hupo Port), Gyeongbuk, rectangular type net pots are mainly used, and in Pohang (Daebo Port) in Gyeongbuk, drum-type pots are mostly used. Enteroctopus dofleini accounts for more than 90% of the catch of octopus. For the octopus fishing performance test by trap type, three types of traps (rectangular pot, drum pot and cylinder pot) were used on the coastal sea of Pohang Daebo. As a result, the total catch by pot shape was shown in the order of rectangular-type pot > drum-type pot > cylinder-type pot. The catch of octopus, the target species, was in the following order: rectangular-type pot > drum-type pot > cylinder-type pot. Such result shows a significant difference (Mann-Whitney test, p<0.05).

• Journal of Korean Society of Forest Science
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• v.46 no.1
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• pp.1-9
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• 1980

This study was carried out to examine the substitution possibility into fiber pot instead of Jiffy pot for the good transplanting. Fiber pot was made of fiber, wood waste particle, and bark powder (10% of the particle weight) and also latex was added into the furnish as a binder. The pots were sprayed with just enough urea solution to prevent nitrogen deficiency of pot media coming from the breakdown of wood fiber in the pot wan during the plant growing. The utility of fiber pot was compared with that of Jiffy pot in the service test of two tree species under a green-house condition. The results obtained can be summarized as follows ; 1. Fiber pot made of 30% wood fiber+70% particle including 10% of bark powder, and 3%-latex has shown a good results like that of Jiffy pot in the sp. gr., tear factor and burst factor. For water absorption, fiber pot made of 50% fiber+50% particle, and 3%-latex got the best result. In the consideration of the above physical and mechanical properties of the fiber pot for good root penetration through the pot wall and facile handling, fiber pot made of 30% fiber+70% particle, and 3%-latex may be seemed to be good. 2. There were no harms in sapling growth in fiber pot as well as in Jiffy pot. The root penetration ability through the fiber pot was slightly inferior to that of Jiffy pot, and yet the pot damage through transportation seemed to be slighter in fiber pot than in Jiffy pot.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.3
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• pp.191-198
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• 2008

Pot life of two-component adhesives such as epoxy resin used in saturating FRP composite is defined as a certain time periods which can guarantee the bond performance and workability of epoxy resin. Therefore, adhesion procedure in strengthening RC members should be completed before chemical hardening is going on at job site. It has been known that there are two types of test method to evaluate the pot life of structural adhesive based on apparent viscosity or temperature change. This study is to verify the test methods how to assess pot life of structural adhesive for FRP composites by means of changing in apparent viscosity and means of exothermic reaction temperature proposed in existing test standards. Results of each test method were compared and analyzed, and reasonable test and evaluation method were suggested.

• Journal of Environmental Health Sciences
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• v.24 no.3
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• pp.48-53
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• 1998

Chitin is known as biodegradable natural polymer. But, in spite of various application of chitin from waste marine sources, commercial use of chitin has been limited due to highly resistance to chemicals and the absense of proper solvents. We made various viscosity of chitosan from chitin by change of Mima's method through the deacetylation which is various condition of NaOH concentration, reaction time and temperature. Also, Polyvinyl alcohol/chitosan blend films were prepared by different solution blends containing the ratio of 5, 10, 15 and 20% chitosan and low, medium, high molecular weight of chitosan to find a more useful biodegradable polymer. Thermal and mechanical properties of PVA/chitosan blend films such as DSC, impact strength, tensile strength and morphological changes by SEM were determined. The 10-15% PVA/chitosan(low, medium) blend films were similar to PVA. Also, PVA/chitosan blend films at the laboratory soil test(Pot Test) were completely degraded in month with four kinds of soils by microorganisms.

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.275-280
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• 1992

Sensory evaluation and Instron test were carried out to study me effect of different cooking methods on the quality of soybean jeolpyon. Cooking methods studied were rice cake steamer, steaming pot, pressure cooker and microwave oven. 1. There were no significant difference in color and flavor between samples cooked by various methods. Moistness of samples by steaming pot and rice cake steamer was similar. Tenderness of samples by rice caker and pressure cooker was better man others. 2. After 24 hours elapsed, me quality of soybean jeolpyon showed me order of by rice cake steamer, steaming pot, pressure cooker and microwave oven. 3. It showed mat soybean ieolpyon by microwave oven was harder man others through Instron test. 4. Hardness of jeolpyons were increased as storage time increased. The rate was higher by pressure cooker and microwave oven man by rice cake steamer and steaming pot.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.99-108
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• 2001

The study was carried out to evaluate characteristics of inorganic phosphate fractions in cultivating soil with paper mill sludge comport(PMSC). The experiment were conducted in cultivating corn by a pot test. The place of the pot test was a plastic house. The pot size was 1/5000a and PMSC was added at rates of 0, 30, and 100 Mg/ha. The pot experiment was divided to two treatments, one in which corn was cultivated and the other which was not. The items of measurement was pH and inorganic phosphate fractions which were determined for the pot tests for 80 days. The results can be concluded as follows, pH increased depending on the higher rates of PMSC application to the soil during the Pot tests, because calcium content was high and contents of nutrient were high. When the application rates of PMSC were increased, Saloid-P and Fe-P decreased, while Al-P and Ca-P in soil increased during the pot tests. According to the increase of PMSC application rates, the growth and the yield of com significantly increased Such results seem to be associated with the higher nutrient level from PMSC application. Although uptake of phosphorus in corn decreased in the corn with increased application of the PMSC, phosphate deficiency didn't appear in the pot test.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.2
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• pp.319-325
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• 2018

Pot-holes are steadily increasing due to abnormal climate such as heavy rainfall and frequent snowfall. Pot-hole related to traffic accidents cause injuries, car damage and distress of road facilities. To reduce pot-holes, the use of an anti-stripping agent is mandatorily recommended to asphalt concrete mixture. Hydrated lime is commonly used as anti-stripping agent due to the convenience and economics. Byproduct ash from circulating fluidized bed boiler was reviewed as an anti stripping agent. According to the test results, the byproduct ash is satisfied with TSR specification using 1% to 3% by weight of the asphalt mixture. The byproduct ash was examined under various condition changes of aggregate and asphalt concrete mixture considering quality movement. According to the results, using the byproduct ash was measured average 0.87 of TSR and coverage rates of 60% after rolling bottle test. Test results also revealed that the byproduct ash showed stable performance. Using the byproduct ash to decrease pot-hole in asphalt concrete pavement is suitable for demonstrating stable performance as anti-stripping agent.

• Journal of Environmental Science International
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• v.24 no.10
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• pp.1253-1264
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• 2015

This study assessed the fertilizing value of struvite deposit recovered from swine wastewater in cultivating Chinese cabbage. Struvite deposit was compared with commercial fertilizers: complex, organic and compost to evaluate the fertilizing effect of struvite deposit. Laboratory pot test obviously presented that the struvite deposit more facilitated the growth of Chinese cabbage than organic and compost fertilizers even though complex fertilizer was the most effective in growing Chinese cabbage. It was revealed that the growth rate of Chinese cabbage was simultaneously controlled by phosphorus (P) and potassium (K). Also, the nutrients such as nitrogen (N), P, K, calcium (Ca) and magnesium (Mg) were abundantly observed in the vegetable tissue of struvite pot. Specifically, P was the most abundant component in the vegetable tissue of struvite pot. Meanwhile, the utilization of struvite as a fertilizer led to the lower accumulation of chromium ($Cr^{6+}$) than other pots, except for compost fertilizer pots, and no detection of cadmium (Cd), arsenic (As) and nickel (Ni) in the Chinese cabbage. The experimental results proved that the optimum struvite dosage for the cultivation of Chinese cabbage was 2.0 g struvite/kg soil. On the basis of these findings, it was concluded that the struvite deposits recovered from swine wastewater were effective as a multi-nutrient fertilizer for Chinese cabbage cultivation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.3
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• pp.204-213
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• 2010

Test fishing was carried out using six kinds of different mesh sizes (20, 22, 24, 28, 35, 40mm) for springnet-pot to study bycatches according to the mesh size and catches survey was done for another one (mesh size : 22mm, entrance round : 350mm) in Geo-je & Tong-young waters of Korea. On the first sea experiment, it was thought that suitable mesh size of spring-net-pot catching conger-eel over 35cm with decreasing the catches of conger-eel (Conger myriaster) below 35cm was 24mm. On the second sea experiment, commercial catches were crabs (Charybdis bimaculata), octopus minor (Octopus variabilis) and others including conger-eel, and catches proportion was 60% of total catches weights. There was no big difference for the monthly catches. Self-consumption catches were 9 species including conger-eel below 35cm holding 50% of catches in the side of weights. There were 40% of bycatches for the catches weights and 63% for catches numbers in the 22mm mesh size of spring-net-pot having entrance round over 140mm. It showed that 50% of catches weights were discarded.