• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.197-208
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• 2003

This paper is to determine the possibility of re-using waste concrete from Incheon city area. The strength test was conducted with five aggregate compounds which was replaced a natural aggregate with recycled aggregate. After checking the physical characteristics of recycled aggregate compounds, the mix design of recycled concrete was conducted. For the relatively comparison between natural and recycled compounds, while the unit aggregate weight was changed, other conditions were fixed. The freezing and thawing test which included fly-ash and super-plastezer were performed to check the durability and workability when recycling waste concrete. In the physical characteristics of recycled aggregate, it was found that the specific gravity of recycled coarse aggregate and recycled fine aggregate satisfied the first grade of recycle specification(KS), and all compounds of recycled aggregate also satisfied the second grade of absorption specification, Especially up to the 50% substitution of recycled aggregate is equal to or a bit lower than that of convention aggregate. In comparison with conventional concrete, the recycled concrete is lower than maximum by 7% in compressive strength decreasing rate after freezing-thawing test. From now, although most of recycled concrete was used to the building lot, subgrade, asphalt admixture, through the result. It was proved that possibility of re-using recycled aggregate as the substructure of bridge, retaining wall, tunnel lining and concrete structure which is not attacked the drying shrinkage severely.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.1
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• pp.1-12
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• 1985

In an attempt todetermine the optimum heat treatment, the changes in TIS content and in vitro protein digestibility of squid, shrimp, oysterand pollock under various heating conditions were studied. The effect of drying method and cold storage on the in vitro digestibility and TIS content were also studied. Optimal boiling conditions were 1 min, for squid, 0.5min. for oyster(eviscerated), 1 min. for whole oyster, and 5 min. for pollock. Steaming times that yieled products with the highest in vitro digestibility value were: 1 min. at $100^{\circ}C$ for squid, 1 min, at $88^{\circ}C$ for oyster and $1{\sim}2.5min$. at $100^{\circ}C$ for pollock. All of freeze dried samples showed the highest in vitro digestibility value and sundried one were comparble to freeze dried samples except high fat level or noneviscerated samples. Fat content was the nain inhivbitory factor of the seafood enzymic digestion during processing and storage. The multi-enzyme assay, used to predict the quality change of dried seafoods stored in a cold room for long periods of raw seafoods treated with various heating methods, offers many advantages over the convetional methods of determining protein quality.

• International Journal of Highway Engineering
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• v.10 no.3
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• pp.149-158
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• 2008

This study was estimated on performance of deicers, corrosion inhibitors and low corrodible deicer used for removal of snow or ice on the road and on influence on structure. The weight loss rate after freezing and thawing of low corrodible deicer is lower than one of deicer, corrosion inhibitors and these combination. Relative dynamic elastic modulus of all except water, low corrodible deicer and NaCl+JF-1004 was radically reduced after freezing and thawing 150 cycles. And concretes after freezing and thawing were showed severe surface damage. It was found that individual use of low corrodible deicer and corrosion inhibitors had a problem of field application because of lack of early ice melting effect and considerably low durability. Products combined with NaCl was showed rapid weight loss by metal corrosion. Therefore, It will need to circumspectly select combination of deicers having low effect on concrete pavement and bridge if possible.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.109-112
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• 2006

Social and environmental pressures draw greater significance on the recycling of the waste. Particularly, waste concrete is particularly crucial among the construction wastes in terms of conservation of natural construction resources as well as disposal crisis. The technology to recycle the waste concrete has been improved. This study has various replacement levels of natural fine aggregate with recycled fine aggregate while coarse aggregate is completely replaced with the recycled coarse aggregate and herein fundamental properties investigated include compressive strength, shrinkage and dynamic modulus of elasticity. As a result, it is anticipated that the recycled aggregate concrete can be successfully applied to structural concrete members provided a proper recycling process, mix design and curing method are practiced.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.105-106
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• 2011

The present tests examined the resistance to freezing and thawing of alkail-activated (AA) slag concrete having compressive strength between 30~56 MPa. To enhance the compressive strength and resistance to freezing and thawing of AA slag concrete, Na ions were used for an activator. Test results revealed that the resistance to freezing and thawing of AA slag concrete is comparable to that of cement concrete when compressive strength is more than 50 MPa.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.18-25
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• 1990

Paralytic Shellfish Poison (PSP) is mainly produced by marine dinoflagellates such as Protogonyaulax sp. and Pyrodinium sp.. The PSP was known to be accumulated in digestive gland of shellfish as result of feeding toxic dinoflagellates. PSP illness when occurs when one eats PSP intoxicated shellfish. Therefore PSP is becoming as serious problem in food hygiene and shellfish cultivation industry. The purpose of this study was to develop detoxification method for utilization of PSP intoxicated sea mussel and prevent from PSP illness. The PSP was extracted with 0.1 N HCl solution from the submitted sea mussel, then the toxicity was measured by mouse assay according to Official Methods of Analysis of the Association of Official Analytical Chemists. No detoxification effect was observed by adding extracted juice of garlic and ginger. When the sea mussel homogenate was heated at various temperatures, the PSP toxicity was not changed significantly at below $70^{\circ}C$ for 60 minutes but it was decreased as the heating temperature was increased. For example, when the sea mussel homogenate was heated at 100, $121^{\circ}C$ for 10 minutes, the toxicity was decreased about 67 and 90%, respectively. When the sea mussel containing 645 $\mu$g PSP per 100g of edible meat was processed according to general shellfish canning procedure, the toxicity was decreased as the level of PSP undetected by mouse assay.

• Clinics in Shoulder and Elbow
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• v.4 no.2
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• pp.166-172
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• 2001

Purpose: To evaluate effectiveness of arthroscopic capsular release combined with manipulation in frozen shoulder. Material and Method: 15 patient who had failed to respond to physical therapy were evaluated, which were treated with arthroscopic capsular release combined with manipulation, from July 1998 to March 2000. Result: At a mean of fifteen months(range, six to twenty four) after the combined procedure, the improvement in the score of Constant and Murley averaged 45 points. The mean improvement in motion was 76 degrees for abduction; 40 degrees and 65 degrees for external rotation in adduction and abduction. Conclusion : Arthroscopic capsular release with manipulation is useful method to treatment the frozen shoulder which was not respond to conservative treatment.

• Asian Journal of Turfgrass Science
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• v.4 no.1
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• pp.49-55
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• 1990

Experiments were conducted to investigate the relationships between the soil freezing depth and the accumulated degree-day of temperature below $0^{\circ}C$ at 17 locations during 1989-1990 winter season in kangwon province. The observed results are as follows : 1.When accumulated degree-day of temperature below at was 141t at late January soil freezing depth of sunny place was 46.5cm, that of shaded lot was 59 cm, and that of marginal place sunny or shaded area was 55cm, in Chun cheon. 2.Accumulated degree-day of temperature below at of Dae gwangryong area was more than that of Un-du, whereas soil freezing depth of Dae gwangryong was lower that of Un-du. It was considered that snow covering worked as heat insulator. 3.Soil freezing depth of vinyl mulching on Zoysia turf was less by around 2Ocm than that of non-vinyl mulching. Rice hulls covering of 4Ocm showed the great heat insulation effects with the soil freezing depth of 1.5cm at sunny place and 6.5cm at shaded lot compared to that of 47cm at sunny and 59.5 cm at shaded place bare ground. 4.Among investingated areas, Dunae, Honeg seong gun was the deepest soil freezing, 89cm with $569^{\circ}C$ of accumulated degree-day of temperature below $0^{\circ}C$ at late February. 5.dehydration of Juniperus C. var. Kaizuca, Euonymus japonica, and Chamaecyparis pisifira at winter season was around 5 %, however dehydration of Vinca minor was more than 10 %. A Studies on the Soil Freezing Depth and Change of Moisture contents in evergreen Plants upon subzero Temperature in Kangwon area.(2)

• Journal of the Korean Geotechnical Society
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• v.37 no.12
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• pp.107-116
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• 2021

In this study, a set of laboratory liquefaction test has been conducted using undisturbed samples collected from Songlim-park, Pohang where liquefaction phenomenon had been observed in 2017. Soil samples were frozen right after tube sampling to minimize the disturbances during transport, storage, and test preparation. Cyclic triaxial test has been carried out to evaluate the liquefaction resistance ratio of undisturbed soil samples. As a result, the liquefaction resistance ratio of samples collected from 8.0~8.8 m and 11.0~11.8 m were almost similar, and these values were approximately 0.04~0.07 larger than values estimated by simplified assessment method using field test results. It is expected that the application of undisturbed sample for the evaluation of liquefaction resistance could contribute to the economical design of geotechnical structures.

• Korean Journal Plant Pathology
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• v.3 no.3
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• pp.180-186
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• 1987

Cell suspensions of two isolates of Pseudomonas syringae. PS8401 from sweet persimon and PS8402 from tea plant, were active in ice nucleation at -2.5 and $-3.8^{\circ}C$, respectively. Ice nucleation at those temperature was, using micropipette method, detected in suspensions ($10^8$ olony forming unit/ml of distilled water) of cells that had been grown on nutrient agar supplemented with $2.5\%$ glycerol. Using the same method, on the other hand, the freezing temperature of distilled water only was approx. $-21.8^{\circ}C$, and those of various plant saps including corn were lower than $-11.6^{\circ}C$. Corn seedlings sprayed with cell suspensions $(10^8\;cfu/ml)$ of nutrient broth) of PS8401 began to be damaged at $-2^{\circ}C$ and were almost completely damaged at $-4^{\circ}C$, whereas seedlings sprayed with nutrient broth only were not injured until the temperature down to $-9^{\circ}C$. Amounts of frost damage measured 48 hr after application of PS8401 suspensions increased as applied bacterial cell densities were increased. Ice-nucleation activity of the cell suspensions in vitro increased with increasing the number of cells in suspension. The activity also affected by growth-medium composition or growth-temperature. Ice nucleation thus occured at -4.0, -4.4 and $-7.2^{\circ}C$ in suspensions $(10^2\;cfu/ml)$ of PS8401 that had been grown at$25\%$ nutrient agar with $2.5\%$ glycerol, nutrient agar with $2.5\%$ glucose and nutrient agar only, respectively, and occured at -4.0 and $-7.6^{\circ}C$ in suspensions $(10^2\;cfu/ml)$ of PS8401 hat had been grown on nutrient agar with $2.5\%$ glycerol at $15\~25^{\circ}C$ and $30^{\circ}C$, respectively.