• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.393-396
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• 2005

This paper presents the results of drying shrinkage of concrete using shrinkage-reducingadmixture(DSRA) studied by the authors through mock-up test. DSRA is proportioned by expansive admixture and shrinkage reducing agent(SRA). Flowing concrete method is also applied to assist the concrete to reduce drying shrinkage by decreasing water content at the same time. The use of EA and SRA does not affect fluidity, bleeding and setting time. Compressive strength of concrete using EA along with SRA exhibited less than that of plain concrete. However, The compressive strength with combination of EA-SRA along with flowing concrete method shows comparable to that of plain concrete. The application of developed method can contribute to reducing drying shrinkage by as much as 30-40$\%$ compared with that of plain concrete.

• Journal of Haehwa Medicine
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• v.9 no.1
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• pp.461-467
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• 2000

After analyzing the datas to propose the rightful recognition and research direction for the long used charcoal, the following conclusions are obtained. 1. The 'soot' is pure Korean which has the meaning of 'fresh power' and is translated in English as charcoal which is composition of china and cool meaning good. 2. The main dispositions of the charcoal are 85% of carbon, 10% of water, 4% of minerals and 2% of essential so that the understanding of properties and effects of carbon are essential. 3. It is usually appeared that there are purifying and detoxifying effects of the woods and the room in practical use of charcoal. 4. In everyday life, it removes the odors, regulates the humidity and prevents the decaying. 5. It is often used medically for activating liver fuctions, regulating digestive fuctions and for diseases with inflammations, fever or bleeding. 6. The charcoal is used in medical treatment internally as well as externally. Above conclusions shows that the objective research is needed for clinical use considering the physical and chemical properties in future.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.1
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• pp.163-169
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• 1999

The object of this study is to compare properties of massive fly-ash concrete with plain concrete. Two concrete mixtures comprising two batch each $1.0m^3$ in volume, were made from ready mixed concrete batch plant. The water-to-cementitious materials ratio was kept constant at 51.4%. Therefore, massive concrete specimen($W800{\times}D800{\times}H800mm$) was cast from ready mixed concrete to analyze history of temperature and core strength properties. Bleeding, time of slump loss and time of setting of the fresh concrete were measured. In order to estimate the properties of massive fly-ash concrete in hardened concrete, non-destructive tests such as rebound hardness, ultrasonic pulse velocity and maturity were performed and analyzed.

• YAKHAK HOEJI
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• v.58 no.5
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• pp.322-327
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• 2014

In this study, we investigated whether the mixtures of onion water extract and aloe ethanol extracts have antiplatelet activities. The mixtures inhibited collagen- and thrombin-induced rat platelet aggregation in vitro. Additionally, the oral administration of the mixtures inhibited platelet aggregation induced by collagen ex vivo but not prolonged mouse tail vein bleeding time in vivo. These results suggest that the combination of onion and aloe extracts has a potential to be a preventive agent against platelet-mediated disorders.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.4
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• pp.73-81
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• 2010

Objectives : The purpose of this study is to establish literatural evidence about thermotherapy and cryotherapy for Korean medicine through literatural review. Methods : Applicable paragraphs which were related to the thermotherapy and cryotherapy of cutaneous and muscle meridian were phrased from in "Yibujicheng(醫部集成) and "Dongyibaojian(東醫寶鑑)" where were archiving of Oriental or Korean medicine literatures. Searched paragraphs were analysed for establishing historical and theoretical bases of thermotherapy and cryotherapy in Korean medicine. Results : Thermotherapy of cutaneous and muscle meridian(經皮經筋溫熱療法) such as hot pack, warm water therapy, paraffin bath, ultrasound is originated from yu(慰) warm water(溫水) hot water(熱水). Matching indications are various pain conditions(caused by coldness(寒), hard-work(僗若), extravasated blood(瘀血), inflammatory skin disease, frostbite and several internal diseases. It also treats gynecological diseases and facial palsy. Diathermic therapy on acupuncture points(穴位照射溫熱療法) such as infra-red, microwave, shortwave is originated from huolu(火爐), wenlu(溫爐), xianglu(香爐), lamp light(燈火). Its objective is to improve the effects of herb medicine by aiding sweating or to treat the residual symptoms of fever disease or to care skin disease and pain from bone fracture, contusion. Cryotherapy of cutaneous and muscle meridian(經皮經筋溫寒冷療法) such as ice pack, ice spray, iced whirpool, cool water bath is originated from lengfu(冷敷), lengtie(冷貼), lengshiyu(冷石熨). Matching indications are contusions, animal bite injury, corn(肉刺) and (淋病), eye disease, nasal bleeding, hemorrhoid, inflammatory skin disease and chicken pox. Conclusions : Thermotherapy and cryotherapy of cutaneous and muscle meridian(經皮經筋溫冷療法) are the treatments which were used in Korean medicine from the ancient Korean medicine. As scientific equipments were originated from yu(慰), huolu(火爐), wenlu(溫爐), xianglu(香爐), lamp light(燈火). lengfu(冷敷), lengtie(冷貼), lengshiyu(冷石熨). It can be said that these are elements of Korean medicine. More rigorous studies are needed to establish clinical evidence about not only thermotherapy and cryotherapy but also the other physiotherapy of Korean medicine.

• Advances in concrete construction
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• v.7 no.2
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• pp.87-96
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• 2019

Self-compacting concretes (SCC) are highly fluid concrete which can flow without any vibration. Their composition requires a large quantity of fines to limit the risk of bleeding and segregation. The use of crushed sand rich in limestone fines could be an adequate solution for both economic and environmental reasons. This paper investigates the influence of quarry limestone fines from manufactured crushed sand on rheological, mechanical and durability properties of SCC. For this purpose, five mixtures of SCC with different limestone fines content as substitution of crushed sand (0, 5, 10, 15 and 20%) were prepared at constant water-to-cement ratio of 0.40 and $490kg/m^3$ of cement content. Fresh SCC mixtures were tested by slump flow test, V-funnel flow time test, L-box height ratio, segregation resistance and rheological test using a rheometer. Compressive and flexural strengths of SCC mixtures were evaluated at 28 days. Regarding durability properties, total porosity, capillary water absorption and chloride-ion migration were studied at 180 days. For the two test modes in fresh state, the results indicated compatibility between slump flow/yield stress (${\tau}_0$) and V-funnel flow time/plastic viscosity (${\mu}$). Increasing the substitution level of limestone fines in SCC mixtures, contributes to the decrease of the slump flow and the yield stress. All SCC mixtures investigated achieved adequate filling, adequate passing ability and exhibit no segregation. Moreover, the inclusion of limestone fines as crushed sand substitution reduces the capillary water absorption, chloride-ion migration and consequently enhances the durability performance.

• Advances in concrete construction
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• v.15 no.5
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• pp.333-348
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• 2023

Fast infrastructure development boosts the demand for shotcrete. Despite sand and stone being the most common coarse and fine aggregates for shotcrete, excessive exploration of these materials challenges the ecological environment. This study utilized an industrial solid waste, high-titanium heavy slag, blended with steel fibers to form Wet Shotcrete of Steel Fiber-reinforced High-Titanium Heavy Slag (WSSFHTHS). It investigated its workability, shotcrete performance and mechanical properties under different water-to-cement ratios, fly ash content, superplasticizer dosage, and steel fiber content. The tunnel excavation and support were investigated by conducting finite element numerical simulation analysis and was used in 3 tunnel lining pipes in Zhonggouwan tailing pond. The major findings are as follows: (1) The water-to-cement ratio (w/c ratio) significantly impacted the compressive strength of WSSFHTHS. The highest 28-day compressive strength of 60 MPa was achieved when the w/c ratio was 0.38; (2) Adding fly ash improved the workability and shotcrete performance and strength development of WSSFHTHS. The best anti-permeability performance was achieved when the fly ash constituted 15%, with the lowest permeability coefficient of 4.596 × 10-11 cm/s; (3) The optimum superplasticizer dosage for WSSFHTHS is 0.8%. It provided the best workability and shotcrete performance. Excessive dosage resulted in water bleeding and poor aggregate encapsulation, while insufficient dosage decreased flowability and adversely affected shotcrete performance; (4) The dosage of steel fibers significantly impacted the flexural and tensile strength of WSSFHTHS. When the steel fiber dosage was 45 kg/m³, the 28-day flexural and tensile strengths were 8.95 MPa and 6.15 MPa, respectively; (5) By integrating existing shotcrete techniques, the optimal lining thickness was 80 mm for WSSFHTHS per simulation. The results revealed that after using WSSFHTHS, the displacement of the tunnel surrounding the rock significantly improved, with no cracks or hollows, similar to the simulation results.

• The Korean Journal of Physiology
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• v.2 no.1
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• pp.47-52
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• 1968

Twenty white rabbits anesthetized with nembutal (30 mg/kg) were employed in this experiment. Five of them served as controls; the remaining rabbits as experimental group were subjected to irreversible hemorrhagic shock. Shock was induced by bleeding the animals until mean blood pressure decreased to a level of 50-40 mmHg. This level of pressure was maintained for 3-4 hours, after which the drawn blood was reinfused. The reinfusion of blood caused the elevation of arterial pressure almost the control level for some minutes, after which a gradual and progressive decline of blood pressure became evident. This decline was thought to be the result from irreversible hemorrhagic shock. When mean blood pressure declined to less than 50 mmHg, chest was opened and samples of arterial blood and left ventricular muscle were taken. Left ventricular muscle and blood plasma were analyzed for potassium, sodium, chloride and water content. Blood glucose concentration was determined by Somogyi-Nelson's method. Extracellular and intracellular myocardial water and electrolyte content were calculated on the basis that electrolytes are distributed between plasma water and interstitial water according to Gibbs-Donnan equilibrium. In this calculation extracellular water was substituted for Na space. The findings obtained were as follows: 1. The concentration of blood glucose was 87mg% in the controls and it rose to 222 mg% in shock (P<0.01). 2. Plasma potassium elevated significantly from 3.3 mEq/l in controls to 8.0 mEq/l in shock (P<0.01), while small decreases in sodium (151-146 mEq/l) and chloride (102-96 mEq/l) were observed (P<0.3, P<0.1), 3. The changes of blood water content (83.1-84.3%) and cardiac water content (77.5-78.3 gm/100gm WT) were observed. 4. In control animals myocardial potassium levels which averaged 30.2 mEq/100 gmDT rose significantly to 40.3 mEq/100 gmDT in shock (P<0.01), while moderate decreases in sodium(16.3-14.3 mEq/100 gmDT) were observed in shock. 5. The calculated transmembrane resting potential of left ventricular muscle of control animals averaged 95 mV, while rabbits in shock averaged 77 mV. (P <0.01). The findings of this experiment do not correspond with the conclusions that myocardial depression seems to be the cause of irreversible hemorrhagic shock, because the excitability of heart muscle is elevated. From the point of view that the lowered transmembrane resting potential, the cause of death in terminal stage of irreversible hemorrhagic shock may be ventricular fibrillation. It can't be said, however, that the lowered transmembrane resting potential is responsible for the transition from reversible to irreversible hemorrhagic shock. The marked increase in blood glucose suggested that glycogenolysis in the liver is favorably active in shock.

• Journal of Periodontal and Implant Science
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• v.27 no.4
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• pp.739-749
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• 1997

The purpose of this study was to assess the antimicrobial and clinical effects of acid water mouthrinse prepared by an electrolysis apparatus on chronic periodontitis and to evaluate the lasting period of these effects. The change' in the pattern of colonization of bacteria within the subgingival pockets was monitored by phase contrast microscopy, in 40 patients, over a period of 8 weeks. In addition, changes in the clinical parameters of the diseased sites were also monitored. Site of pocket ${\geq}$ 5mm was selected in each patient randomly divided into two groups. As a test group, acid water mouthrinse was used twice a day in 20 patients. As control, no mouthrinse was used in 20 patients The results were as follows : 1. The suppression of motile bacteria was maintained for up to 3-4 weeks at test group. 2. Two groups did not differ significantly in proportion of bacteria in subgingival plaque over a period of 8 weeks. 3. Loss of attachment showed a significant difference in test group and in test group compared with control group (P<0.05), but there was no significant difference in control group. 4. No statistical difference was shown in two groups concerning the gingival index, plaque index, bleeding index. The results suggest that acid water mouthrinse is effective for reducing subgingival bacteria. It can be concluded that acid water may be useful as an mouthrinsing agent.

• Journal of Marine Life Science
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• v.1 no.1
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• pp.18-24
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• 2016

Since April 2012, doctor fish in the breeding tank and in the quarantine tank in Hanwha Aquaplanet Yeosu Aquarium have been dying, accompanied by diffuse bleeding around the mouth, in the chin, and at the bottom of the abdomen. In this study, the cause of death would be examined through the bacteriological study of doctor fish and the rearing water quality in the aquarium. The water quality and the bacterial counts of the rearing water in the exhibit tank and in the quarantine tank were analyzed once a week, starting from August to November 2014. Water quality was measured based on the following data: temperature was in the range of 24.5~26.8℃, pH at 6.77~7.94, DO at 6.15~8.61 ppm, ammonia at 0~0.93 ppm, nitrite at 0.009~0.075 ppm, and nitrate at 1.1~40.9 ppm. Studies revealed that the differences in these water quality factors were not related to the death of doctor fish. Bacterial counts in the rearing waters of Garra rufa slightly increased to 10³~10⁴ CFU/ml, just before the death of the doctor fish. Twelve strains of bacteria were isolated from the dead fish and rearing waters. The isolates were identified as Aeromonas veronii, Citrobacter freundii, Pseudorhodoferax aquiterrae, Shewanella putrefaciens, and Vibrio anguillarum on the basis of 16S rRNA gene sequences. The most dominant species was C. freundii, which showed medium sensitivity to florfenicol and norfloxacin, and was resistant to amoxacillin, doxycycline, oxytetracycline, tetracycline, and trimethoprim. Ten isolates were confirmed to be pathogenic to the doctor fish. Doctor fish infected with C. freundii and S. putrefaciens showed high mortality in the experimental groups. These results indicate that the variation in bacterial numbers in the rearing water was related to the death of doctor fish. C. freundii and S. putrefaciens were directly implicated in causing the death of doctor fish in the aquarium.