• Journal of Environmental Science International
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• v.10 no.2
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• pp.113-117
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• 2001

This study was conducted to investigate the effect of the prechlorination on algal removal by application of a varying amount of different coagulants, such as LAC, PAC, PACS following the process of coagulation and sedimentation of algae in the Nakdong River. The samples used as a source for the raw water of the Nakdong River were collected from the D Water Purification Plant in Taegu city. With the application of the process of prechlorination, the removal rate of the algae was increased from 10~25% for Synedra spp., 20~35% for diatoms and 4~17% for turbidity. Generally, the removal rate of the algae was increased with the increase of the concentration of the coagulants. The PAC and PACS showed 5% higher removal rate for turbidity as compared to the LAS. On the hand, LAS showed 12% higher removal rate for Synedra spp. as compared to the PAC and PACS. The variations in the removal rate of diatoms with the change of coagulant were not significant. In conclusion, the application of LAS, polymeric coagulant and chlorination for at least 20 minutes could be considered as a reliable treatment process for the removal of source water containing a variety of algae.

• Fashion & Textile Research Journal
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• v.13 no.3
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• pp.425-431
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• 2011

The purpose of this study was to investigate washing effects according to the rinsing conditions and the characteristics of soiled fabrics. In this study rinsing conditions including rinsing cycle, time, temperature, and bath ratio were examined. The foamability of rinsing bath was also examined. The quantity of LAS in the rinsing bath and extracts of test fabrics was analyzed after washing and rinsing, respectively. The results of these experiments were as follows: The washing effects of soiled fabrics were varied from the kinds of soils and rinsing conditions. The removal of soils from fabrics was increased by the first rinsing after washing effectively. The priorities of rinsing conditions were rinsing temperature> rinsing time > rinsing cycles> references. Foamability was result from residual LAS in rinsing bath and fabrics extracts after rinsing. The residual quantity of LAS was references > rinsing cycles> rinsing time> rinsing temperature, which shown rinsing temperature was the most efficient factor of the rinsing performance.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.3
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• pp.632-640
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• 1997

Changes in surface properties and detergency of sunactant mixtures were investigated in order to study the optimum mixing ratio of anionic and nonionic surfactants by measuring surface tension, interfacial tension, suspendability, and emulsification as a Amction of mixing ratio. Also, surface tension and detergency of the surfactant mixtures were determined with the increase of water-hardness or temperature. The results were as follows: the addition of NPE to anionic surfactant solutions (LAS or SDS) by 0.1 mole fraction remarkably decreased surface tension. NPE (n=15)/anionic surfactant mixtures showed a synergistic effect in lowering interfacial tension and emulsification, but NPE (n=7.5)/anionic surfactant mixtures did not. In suspension stability, however, synergism appeared when LAS or 505 was mixed with both of NPE's. With respect to the hydrophile of NPE, NPE (n=15) was more effective than NPE (n=i.5) in improving suspension stability. Detergency of LAS/NPE mixture changed almost linearly with mixing ratio, but that of SDS/NPE mixture increased remarkably by the addition of 0.1 or 0.2 mole fraction of NPE at all temperatures. As the temperature increased, surface tension of surfactant mixtures decreased and detergency was improved, but their synergistic effect decreased. In hard water, the mixtures showed better detergency than single surfactuant solutions.

• Korean Journal of Applied Biomechanics
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• v.33 no.3
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• pp.94-100
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• 2023

Objective: Few studies have investigated alterations of ground reaction force (GRF) in individuals with chronic ankle instability (CAI) compared with lateral ankle sprain (LAS) copers and healthy controls during walking. This study aimed to investigate differences in GRF variables among the CAI, LAS coper, and control groups. Method: Eighteen individuals with CAI, 18 LAS copers, and 18 healthy controls were recruited for this study. All participants walked on 8-m walkway with a force plate three times. GRF data during stance phase were extracted and analyzed. The analysis of variance and ensemble curve analysis were used for statistical analyses of discrete points and time-series data respectively. Results: The CAI group showed a greater loading rate (LR) and a shorter time to impact peak force than the other groups, as well as decreased vGRF from 56% to 65% in the stance phase than the control group. No significant differences were noted in the other variables. Conclusion: Based on these findings, individuals with CAI should enhance their ability to create propulsion during the push-off phase and spend more time absorbing GRF to decrease the LR, which is considered one of risk factors for overuse injury and ankle osteoarthritis.

• Journal of the Korean Society for Library and Information Science
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• v.40 no.3
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• pp.99-120
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• 2006

This study is conformed to having library anxiety of our domestic university library users. and. to developing the Korean Library Anxiety Scales(K-LAS). The research methods is literature research. library use Postscript report analysis. and questionnaire survey. The research subjects were selected to be 4 universities in consideration of their student number and library scale. The research period was from September 3, 2005 to March 23. 2006. The questionnaire survey was administered in the liberal arts courses which all the students could take. The development method of the Library Anxiety Scale are the content validity test by expert group. reliability test and validity test of SPSS Program. Also. the correlation between library variables and library anxiety was tested by using K-LAS. The results of this study developed the K-LAS. which was composed of 6 factors and 40 items. 6 factors were set up as physical environmental factor, library use and knowledge factor, task and research factor. digital information factor, and the factor on library staff. and Psychological ? emotional factor. According to the Post-test results of the correlation between library anxiety and variables. 5 factors except the factor on library staff were correlated with more than 2 variables respectively.

• Journal of Korean Society of Water and Wastewater
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• v.9 no.3
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• pp.116-126
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• 1995

The purpose of this study was to investigate the removal of ammonium nitrogen by biological nitrification in raw water containing LAS using BAC. At batch teats, LAS removal by ozone followed the first order reaction, and the rate constants(k) by ozone dose 1, 3mg/min.L were $0.040min^{-1}$, $0.062min^{-1}$ respectively. Therefore, the more ozone was dosed, the higher LAS was removed The reaction between ozone and ammonium nitrogen also followed the first order, and rate constants(k) at pH7,8 and 9 were $8.9{\times}10^{-4}min-1$, $3.8{\times}10^{-3}min^{-1}$, and $2.9{\times}10^{-2}min^{-1}$ respectively at ozone dose of 3mg/min.L . Therefore, ammonium nitrogen was little removed by ozone under neutral pH of 7. The continuous flow apparatus had four sets composed of a ozone contacter and a GAC column. Through continuous filtration test for 50days, the following conclusions were derived; (1) LAS was removed 23%, 30% respectively by ozone dose 1, 3mg/L, and was not detected in all column effluents during the period of experiment. Therefore, it appeared that adsorption capacities of each column still remained. (2) Ammonium nitrogen concentration after ozone contact varied little in raw Water because pH of raw water was from 6 to 7, and was transfered to nitrite and nitrate within GAC columns as the result of staged nitrification. After 30days, nitrite was not detected in all column effluents due to biological equilbrium between nitro semonas and nitrobacter Average removals of ammonium nitrogen in each column after the lapse of 30days were the following; ${\cdot}$ column A (ozone dose 3mg/L, EBCT 9.5min): about 100% ${\cdot}$ column B (ozone dose 1mg/L, EBCT 9.5min): 91% ${\cdot}$ column C (ozone dose 3mg/L, EBCT 14.2min): about 100% ${\cdot}$ column D (ozone dose 0mg/L, EBCT 9.5min): 53% Though column A and C reached nitrification of about 100%, column C (longer EBCT than column A) was more stable than column A. (3) After backwash, nitrification reached steady state within 5 to 8 hours. Therefore, nitrification was not greatly affected by backwash. (4) According to the nitrification capacity in depth of column A, C, where 100% nitrification occured. LAS was removed within 20cm, while ammonium nitrogen required more depth to be removed by nitrification.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1414-1417
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• 2000

This study was to investigate effects of the supplementation of the different lactic acid bacteria[Streptococcus thermophilus KCTC 2185 culture group(ST), autoclaved Streptococcus thermophilus KCTC 2185 culture(STS), Lactobacillus acidophilus ATCC 4356 culture group(LA) and autoclaved Lactobacillus acidophilus ATCC 4356(LAS)] on suppression of aluminum accumulation in organs of rats fed with the diet containing $250\;{\mu}g/g$ aluminum sulfate for 4 weeks. Amount of aluminum accumulation in the control rat was in order of bone>lung>heart>large intestine>kidney>liver>brain>small intestine. Effects of reduction of aluminum accumulation by feeding of the four difference fermented milk were in order of LA group>LAS group>ST group>STS group. ST and LA both were more effective than STS and LAS. Ultimately fermented milk was useful in reduction of toxication by accumulating of aluminum in vivo.

• Proceedings of the Culinary Society of Korean Academy Conference
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• 2006.07a
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• pp.152-152
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• 2006

• Proceedings of the Materials Research Society of Korea Conference
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• 1996.05a
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• pp.92-92
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• 1996

• KASI NEWSLETTER
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• s.85
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• pp.5-5
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• 2009