• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.6
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• pp.30-36
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• 2003

Variable valve timing(VVT) mechanisms are used widely for improving fuel consumption and reducing emissions. Most of application, however, are limited in the DOHC engine. Dual equal retard/advance strategy is relatively simple one and can be applied to both SOHC and DOHC engines. In this study, effects of dual equal valve timing retard/advance are investigated to observe the feasibility of VVT system on an SOHC SI engine. The result shows that fuel economy and emissions are improved in the dual retard condition due to increased internal EGR. Some amount of increase in volumetric efficiency can be achieved by advancing valve timing at low speed and by retarding at high speed. In this case, however, full load power is not so much improved as the volumetric efficiency increases because of severe knock. In the dual advance condition, there is no merit in the fuel economy and emission.

• Journal of Korean Society on Water Environment
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• v.23 no.5
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• pp.748-755
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• 2007

To develop an efficient pump operating rule for a retard basin, it is necessary to estimate inflow to the retard basin accurately which is affected by the backwater effect at the outlet of the conduit. The magnitude of the backwater effect is dependent on the water depth of a retard basin; however, the depth is determined by the amount of inflow and outflow. Thus, a real time simulation system that is able to simulate urban runoff and the pump operation with the consideration of the backwater effect is required to estimate the actual inflow to a retard basin. With this system, the efficient pump operating rule can be developed to diminish the possible flood damage on urban areas. In this study, a realtime simulation system is developed using the SWMM 5.0 DLL and Visual Basic 6.0 equipped with EXCEL to estimate inflow considering the backwater effect. The realtime simulation can be done by updating realtime input data such as minutely observed rainfall and the depth of a retard basin. Using those updated input data, the model estimates actual inflow, the amount of outflow discharged by pumps and gates, the depth of each junction, and flow rate at a sewer pipe on realtime basis. The developed model was applied to the Joonggok retard basin and demonstrated that it can be used to design a sewer system and to estimate actual inflow through the inlet sewer to reduce the inundation risk. As results, we find that the model can contribute to establish better operating practices for the pumps and the flood drainage system.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.165-172
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• 2016

Since the advent of digital games with hardware development a key component of the game characters are changed to retard the rate at which types of users based on their favorite theory of human proportion. Many popular to gamers in the game according to the change in the retard rate in a unique image of the character. Studies on the head and body proportion are thought that up to now been insufficient. The purpose of this study is to examine a fundamental human proportion that has importance as a molding factor in the game character development, it investigated the characteristics of the game character, and classifying the retard rate of the game character, through the research method of analyzing the results, into the retard rate look for and investigate studying the effect on future game images. Five types of game characters that make up the analysis were analyzed with a unique image, and the more specialized users prefer retard rate, the figurative exaggeration to retard rate than the actual main body. Utilizing a bit exaggerated the difficulties of the character looks relatively small proportion character in the graphic wallpaper increased visibility. The proportion of a game character through the study is considered as a very important factor as the game image in the game development.

• Archives of Pharmacal Research
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• v.26 no.7
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• pp.569-574
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• 2003

Controlled-release amitriptyline pellets (ATP) were formulated and its oral bioavailability was assessed in human volunteers after oral administration under fasting conditions. Core pellets were prepared using a CF granulator by two different methods (powder layering and solvent spraying) and coated with Eudragit RS or RL 100. Physical characteristics and dissolution rates of core pellets and coated pellets were evaluated to optimize the formulation. Powder layering method resulted in a better surface morphology than solvent spraying method. However, physical properties of the products were poorer when prepared by powder layering method with respect to hardness, friability and density. The dissolution profile of amitriptyline coated with Eudragit RS 100 was comparable to that of commercially available amitriptyline enteric-coated pellets ($Saroten^{\circledR}$ retard). After the oral administration of both products at the dose of 50 mg, the mean maximum concentrations ($C_{max}$) were 36.4 and 29.7 ng/mL, and the mean areas under the concentration-time curve ($AUC_{0-96}$) were 1180.2 and 1010.7 ng.h/mL for ATP and Saroten retard, respectively. The time to reach the maximum concentrations ($T_{max}$) was 6 h for both formulations. Statistical evaluation suggested that ATP was bioequivalent to Saroten retard.

• Journal of the Korean Society of Costume
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• v.57 no.9
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• pp.136-148
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• 2007

The purpose of this study was to identify make-up benefits sought and attitudes according to the fashion lifestyle of silver women. Self-administered questionnaire was used for data collection, and subjects were silver women aged over 55 years. The results were as followed: 1. The factors of fashion lifestyle of silver women were clothing ostentation, leisure activity, interest in appearance, self-confidence, clothing conservation, and economics in clothing, and total variances was 70.99%. Silver women were clustered into high fashion-involvement group, medium fashion-involvement group, low fashion-involvement group, and fashion retard group according to fashion lifestyle. 2. High fashion-involvement group included more silver women with higher education and incomes, but fashion retard group included more with lower education and income. 3. High fashion-involvement group pursued self satisfaction, complement of defects, fashion trend following, politeness to others highly through make-up, and had higher concern and knowledge about make-up, and accepted plastic surgery or skin care positively. But fashion retard group pursued only a little and showed negative attitudes toward plastic surgery or skin care.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.6
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• pp.82-88
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• 2000

The effect of the welding for the offshore structure in the TMCP steel on the fatigue crack propagation rate and crack opening-and-closure behavior was examined. The welding anisotropy of the TMCP steel and crack propagation characteristics of the excessive loading were reviewed. (1) It seemed that a heat which was generated by the welding made a compressive residual stress over the base metal, so fatigue crack propagation rate was placed lower than in case of the base metal. (20 In the base metal, an effect of the anisotropy which has an effect of fatigue crack propagation rate of the excessive load and the constant amplitude laos was not found but in the welding material case, fatigue crack propagation rate of the excessive load in the specimen of the width direction was located in the retard side as compared with a specimen rolling direction. (3) A crack opening ratio of the used TMCP stel in this study was not changed after excessive loading but a retard phenomenon of crack propagation was observed. Consequently, it was thought that all of the retard phenomenon of crack propagation did not only a cause of the crack opening-and-closure phenomenon.

• International Journal of Automotive Technology
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• v.6 no.6
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• pp.585-590
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• 2005

The effects of spark timing and exhaust valve timing change on exhaust gas temperature during cold start period of an SI engine are studied through engine bench tests. The exhaust gas temperature increases when the spark timing or valve timing are retarded individually, due to late combustion or slow flame speed. Therefore, exhaust gas temperature shows a large increase when the two timings are retarded simultaneously. However, it is considered that combustion stability during cold start deteriorated under these retarded conditions. To increase exhaust gas temperature for fast warmup of catalysts while maintaining combustion stability, an optimal condition for spark and valve timing retard should be applied for the cold start period.

• Journal of Pharmaceutical Investigation
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• v.17 no.2
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• pp.47-53
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• 1987

Furosemide retard tablets were prepared using hydroxyethylcellulose(HEC) as a matrix material. Dissolution of furosemide from this tablet was retarded significantly comparing with conventional tablets and greatly dependent on HEC concentration and pH of the dissolution medium. The mechanism of retarded release was supposed to be due to HEC gel formation and drug diffusion through the gel matrix.

• 한국환경농학회:학술대회논문집
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• 2009.07a
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• pp.93-115
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• 2009

There are growing public concerns over crop and food safeties due to the elevated levels of heavy metals grown in contaminated soil. Heavy metals are classified as the chemical harmful risks for crop and food safety. With implementation of GAP, crop safety is controlled by many regulatory options for soil, irrigation water and fertilizers. Any attempt to retard the metal uptake by crops may be the best protocol to secure crop and food safety. This article reviews the management strategies for heavy metals in view of crop safety in Korea and demonstrates results from the field experiments to retard metal translocation from soil to crops by using chemical amendments and soil layer management methods. Major source of soil pollution by heavy metals has been related with mining activities. Risk assessment revealed that rice consumption and groundwater ingestion in the abandoned mining areas were the major exposure pathways for metals to human and the heavy metal showed the toxic effects on human health. Chemical amendments such as lime and slag retarded Cd uptake by rice (Oryza sativa L.) by increasing soil pH, lowering the phytoavailable Cd concentration in soil solution, immobilizing Cd in soil and converting the available Cd fractions into non-available fractions. The soil layer management methods decreased the Cd uptake by 76% and Pb by 60%. Either reversing the surface layer with subsurface layer or immobilization of metals with layer mixing with lime was considered to be the practical option for the in-situ remediation of the contaminated paddy soils. Combination of chemical soil amendments and layer management methods was efficient to retard the metal bioavailability and thus to secure crop safety for heavy metals. This protocol seems to be cheap, relatively easy to practice and practical in the agricultural fields. However, a long term monitoring work should be followed to verify the efficiency of this protocol.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.92-93
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• 2003

Chemoprevention refers to the use of agents to inhibit, reverse, or retard tumorigenesis. Numerous phytochemicals present in edible plants have been reported to interfere with a specific stage of the carcinogenic process. Some antioxidative and anti-inflammatory substances derived from dietary or medicinal plants exert chemopreventive properties by targeting intracellular signaling molecules or events.(omitted)