• Journal of the Korean Recycled Construction Resources Institute
• /
• v.8 no.1
• /
• pp.33-40
• /
• 2013

The cement industry brought very severe environment problems with massive carbon dioxide during its production. To solve this problem, attempts on Alkali-Activated Slag (AAS) concrete that perfectly substitutes industrial by-products such as ground granulated blast furnace slag (GGBFS) for cement are being actively made. AAS concrete is possible to have high strength development at room temperature, however, it is difficult to ensure the working time due to the fast setting time and the loss of workabillity because of the alkali reaction. In this study, the early age properties of alkali activated slag mortar are investigated to obtain the fundamental data for AAS concrete application to structural members. The water-binder ratio (W/B) was fixed at 0.35 and sodium hydroxide and waterglass as alkali activator was used. The compressive strength, the flow and the ultrasonic pulse velocity were measured according to the type of superplasticisers, which were naphthalene(N), lignin(L), melamine(M) and PC(P), up to a maximum of 2 percent by the mass of GGBFS. The results showed that adding melamine type of superplasticizer improved the fluidity of AAS mortar without decreasing the compressive strength, while naphthalene and polycarbonate type of superplasticizer had little effect on the fluidity of AAS mortar.

• Korean Journal of Construction Engineering and Management
• /
• v.8 no.1 s.35
• /
• pp.66-77
• /
• 2007

With the electricity industry structure reformation of the government in April, 2001, Korea Power Electric Corporation was divided in to Korea water power nuclear power and 5 thermal power plant. After, various delivery method is introduced and applied for active profit creation according to the competition between each development companies for the public company privatization. However, the current situation does not satisfy the project participant by selecting the delivery method without reflecting the business goal and project characteristics of power plant construction business. The objective of this study is to research the influencing factors that should be considered to select the delivery method in thermal power construction business and develop a standard of selection of appropriate delivery method through questionnaire and interviews to establish a model to select the delivery method that fits the business goal of the subject of delivery. In the future, if the delivery method selection model suggested in this study is applied, it is expected to select the appropriate delivery method of power plant construction business by effectively reflecting the business goal, characteristics and demand of the delivery subject, and characteristics of the construction business apart from the existing customary practices that decided the delivery method dependent on the subjective and experience based judgement.

• Fashion & Textile Research Journal
• /
• v.17 no.4
• /
• pp.657-665
• /
• 2015

This study evaluated the thermoregulatory properties of functional thermal underwear ('heating underwear') in markets using a thermal manikin and human wear trials. One ordinary thermal underwear (ORD) and two functional thermal underwear (HEAT1 and HEAT2; manufactured goods, HEAT1: moisture absorbing heat release mechanism, HEAT2: heat storage, release mechanism) were chosen. Thermo-physiological and subjective responses were evaluated at an air temperature of $5.0{\pm}0.5^{\circ}C$ and air humidity of $30{\pm}5%RH$ with five male subjects ($21.6{\pm}1.3yr$ in age, $178.0{\pm}5.9cm$ in height, $68.2{\pm}5.9kg$ in body mass). Experimental conditions consisted of four ensembles that included winter clothes (Control: no underwear, ORD, HEAT1, HEAT2). Water-vapor resistance was greater in fabric of HEAT1 than others. The results were: 1) Total thermal insulation (IT) using a thermal manikin were not greater for HEAT1 (0.860clo) and HEAT 2 (0.873clo) than for ORD (0.886clo). 2) There were no significant differences in rectal temperature, mean skin temperature, heart rate and total body mass loss between the four conditions. Microclimate clothing temperature on the back was greater for ORD than for HEAT1 and HEAT2. Subjects felt more comfortable with HEAT1 than for others at rest. HEAT2 was higher in microclimate humidity when compared to other conditions. The results suggest that thermoregulatory properties of 'heating underwear' in market did not differ from those of ordinary thermal underwear in terms of total thermal insulation and thermoregulatory responses in a cold environment.

• Korean Journal of Environmental Biology
• /
• v.23 no.2 s.58
• /
• pp.146-151
• /
• 2005

Recent studies indicated the utility of whole effluent assessment as a measure to control discharge of toxic effluents to receiving water in Korea. However, most studies have been focussed on acute lethal effects of toxic wastewater with little consideration of chronic sublethal impacts which are of growing concern in protecting aquatic ecosystem. We conducted acute and chronic toxicity tests with effluents discharged from five different dyeing plants in Gyeong-gi province using a marine bacterium Vibrio fischeri and a freshwater macroinvertebrate Daphnia magna to demonstrate the importance of assessing chronic sublethal effects. Various levels of acute and chronic toxicities were observed in many samples tested in this study. In 21-d chronic toxicity tests using D. magna all samples showed effects on reproduction and growth. Notable mortalities were also noted in three out of five effluents. The result of the Microtox assay indicated that acute microbial toxicity existed in effluents from two out of five plants and acute daphnid toxicity was observed in only one effluent. The result of this study clearly suggests chronic toxicity tests are more suitable to assess biological effects of effluents because it was shown from this study that even an effluent with no acute toxicity could cause chronically lethal and/or sublethal adverse effects on aquatic biota which may affect the population dynamics in aquatic ecosystem.

• Explosives and Blasting
• /
• v.28 no.2
• /
• pp.99-107
• /
• 2010

Domestic explosive demolition techniques have been developed and applied for low-rise structures up to now. However, the demand for the development of those techniques that can be applied economically, safely and environment-friendly rapidly increases because the old high-rise RC rahmen structures that were built since around 1970s are now required to rebuild. As a result, element technologies of explosive demolition for low-rise structures were applied to take advantage of technology in high-rise structures that performed application testing at Chungang Department demolition field in Daejeon city. It could judge elements technology establishment for high-rise structure demolition and field application and suggest the improvements when the problems occurred to develop High-rise building demolition techniques for method of protection a field test and the dust reduction test. The water cannon test was applied to reduce the dust site and the drilling tests are performed to select the best components for explosives demolition elements techniques of the reliability. This paper shows that we have the ability to remove a high-rise building using environmentally friendly safe and economical explosives demolition method. It would contribute to prevent a foreign company from entering the domestic market and should contribute to acquire competitiveness of domestic demolition industry.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.31 no.12
• /
• pp.1653-1661
• /
• 2007

The research aimed to establish the standard extraction procedure for examining brazilin, the major chromophoric substance of Sappanwood, using GC-MS with the ultimate goal of identifying the sappanwood dye in severely faded archaeological textiles. The amount of brazilin represented by the GC abundance was the largest when acetone was used as the extraction medium, followed by methanol. Shaking plate operated at room temperature was more effective than the waterbath shaker which was operated at $30^{\circ}C$. In both cases, the extraction method which incorporated one hour pre-soaking before the 12 hours of actual extraction resulted in a larger amount of brazilin detection than the extraction procedure without the one hour pre-soaking. In case of water extraction, pH 5 resulted in the most effective pH level for the extraction of brazilin, The best GC-MS parameter for detecting brazilin was to set the column temperature initially at $50^{\circ}C$. gradually increase to $210^{\circ}C$ at a $23^{\circ}C/min$ rate, finally increase to $305^{\circ}C$ at $30^{\circ}C/min$ rate, and hold for 14 minutes, and the MSD scan range at $75{\sim}400m/z$.

• Journal of Food Hygiene and Safety
• /
• v.29 no.3
• /
• pp.165-169
• /
• 2014

Salmonella spp. and Brucella spp. are associated with considerable diseases of both humans and animals. In addition, these microorganisms cause the economic loss in animal farming and food industry. In this study, the disinfection efficacy of a commercial disinfectant, composed to povidone-iodine was evaluated against S. typhimurium and B. ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at $4^{\circ}C$. The disinfectant and test bacteria were diluted with hard water (HW) or organic matter suspension (OM) according to treatment condition. On HW condition, the bactericidal activity of the disinfectant against S. typhimurium and B. ovis was 400 and 150 fold dilutions, respectively. On OM condition, the bactericidal activity of the disinfectant was 5 and 20 fold dilutions against S. typhimurium and B. ovis, respectively. As the disinfectant composed to povidine-iodine possesses bactericidal efficacy against animal pathogenic bacteria such as S. typhimurium and B. ovis, the disinfectant solution can be used to control the spread of bacterial diseases.

• The Journal of the Korea Contents Association
• /
• v.6 no.11
• /
• pp.182-189
• /
• 2006

Consumers can choose suitable shoes for their feet in off-line shopping. However, in on-line shopping, because they can not wear shoes, compare to the off-line shopping, there are many problems in internet shopping. And the solution of user-oriented internet shopping is development of new type of prototype which is accessible to user and to offer visual information through 3D-virtual reality. We made this Prototype that the consumer can measure their own shoes size. And the consumer can print out their foot size in the internet database and measure their own foot size and type. And we maximized the visual experience though it is indirect and then we wanted to overcome a emotional experience in the real world. we visualized first, 'the softness' of shoes meterial, second 'the drainage' in the realtion of shoes meterial and water, third 'the close adhesion' in the realtion of shoes and consumer's their own foot and last 'the elasticity' in the relation of the shoes outer sole and surface. The result of this research can solve the problem in the existing on-line shoes' shop and it will become an alternative plan. And this prototype just will not become the localization at the on-line shoes' shop. In true sense, it will be an important example in the whole internet industry.

• Toxicological Research
• /
• v.23 no.1
• /
• pp.87-96
• /
• 2007

Single and repeated-dose toxicity of anti-diabetic herb extract microcapsule (ADHEM) were evaluated according to Toxicity Test Guidelines of Korea Food and Drug Administration using Sprague-Dawley rats. For single-dose toxicity test, kneading ADHEM with sterilized water were administered orally once at dose levels of 0 and 2,000 mg/kg and examined for 14 days. No dead animals, clinical signs and abnormal necropsy findings were observed and also no significant difference in body weights was found. Therefore, the $LD_{50}$ of ADHEM was considered to be higher than 2,000 mg/kg in both male and female rats. For repeated-dose toxicity test, ADHEM were mixed with powder fodder and administerd orally for 28 days at dose levels of 0, 500, 1000 and 2000 mg/kg/day. No dead animals, clinical signs and significant difference in body weights were found. In hematology and serum biochemistry, all values were included within the normal ranges. In relative organ weights, kidney or liver were significantly increased in the 500, 1000 or 2000 mg/kg/day male groups, uterus was significantly increased in the 500 mg/kg/day female group and left adrenal glands were significantly decreased in the 2000 mg/kg/day female group. In histopathological examinations, vacuolation and microgranuloma in the liver, chronic progressive nephropathy and inflammation in the kidney were observed in the 500, 1000 or 2000 mg/kg/day both male and female groups. Therefore, the no observed adverse effect level (NOAEL) of ADHEM was considered to be lower than 500 mg/kg/day in both male and female rats.

• Korean Journal of Veterinary Research
• /
• v.47 no.3
• /
• pp.291-298
• /
• 2007

Olive flounder, Paralichthys olivaceus is one of the most important cultured fish in Korea, its farming has been negatively impacted by viral, bacterial and parasitic diseases. Streptococcal infection was considered as a serious problem because of significant economic losses in olive flounder farm industry. The development and evaluation of vaccine for protection against infection by this agent were required. We evaluated the safety and efficacy of ${\beta}$-hemolytic Streptococcus (S.) iniae vaccine on olive flounder Three hundreds of flounders (weight $119.8{\pm}20.7g$, body length $22.6{\pm}1.4cm$) were reared in 0.5 tons aquaria in land-marine tank system. Seawater was provided from the sea of Inchon in Korea, and water temperature was set to $22^{\circ}C$ and $25^{\circ}C$ in the vaccination and challenge test, respectively. We used the formalin-inactivated ${\beta}$-hemolytic S. iniae (F2K) vaccine (M VAC INIAE; Kyoritsu seiyaku, Japan) originated in Japan. The vaccine was intraperitoneally administered to fish. Both of vaccinated group and control group were challenged with intraperitoneally injection by virulent S. iniae SI-36 isolates with $1.0{\times}10^7CFU/fish$ at 3 weeks after vaccination. Difference on mortality of control and vaccinated group (90.0 and 15.0%, 76.5 and 8.0% respectively) at two trials were found significant (p<0.05), and relative percent survival were 83.4% and 89.5%, respectively. The dead fishes were showed dark pigmentation of skin, abdominal extension, hemorrhagic ascites, and liver necrosis, and isolated the S. iniae strain from ascites, liver and kidney. We confirmed the safety and efficacy of ${\beta}$-hemolytic S. iniae vaccine by determinations of the optimal management condition and artificial challenge test in olive flounder.