• Journal of the Korean Geotechnical Society
• /
• v.32 no.11
• /
• pp.21-29
• /
• 2016

In this study, recycled aggregates crushed from waste concrete were sorted into three groups, 10-13 mm, 13-20 mm, and 20-25 mm. They were treated in different ways and then their crushability was evaluated for each treatment. Coffee waste was used for reducing their pH level. The pH of recycled aggregate was almost 11, regardless of aggregate sizes. The pH of coffee waste was nearly 5 and 10, 30, or 50 g of coffee waste was mixed with 1000 ml of distilled water and recycled aggregates. The lowest pH was about 6.2 when 50 g of coffee waste was mixed. Aggregates were treated with microwave or soaked for 1 day in vinegar (pH = 2) for neutralization reaction. Microwave treated and neutralized aggregates showed 3.3% and 6.2% higher crushing values compared to non-treated one, respectively. Neutralized treatment was more effective for crushing. In crushing tests, a sample height of 120 mm was tried, which gave 6.3% higher crushing value. A four stepped loading with each 100 kN gave 7.1% higher crushing value, compared to standard 100 mm height and 400 kN continuous loading.

• Phonetics and Speech Sciences
• /
• v.5 no.1
• /
• pp.55-62
• /
• 2013

This study compared the aerodynamic multiparameters of whispers and phonation in patients with muscle misuse dysphonia(MMD) to evaluate the voice aerodynamic analysis for discrimination between whispers and phonation. Eleven patients with muscle misuse dysphonia were examined. Whispers were shorter with a maximum phonation time(MPT; p<.01), a lower phonatory sound pressure level(SPLp; p<.01), a higher phonatory flow rate (PFR; p<01), lower phonatory efficiency(PE; p<.01), and a lower phonatory resistance (PR; p<.05) than phonation. The subglottal pressure level was not significantly different between whispers and phonation. (Psub; p>.05). The ROC analysis showed that the threshold of 23.83 ppm for PE achieved a good classification for whispers, with the perfect sensitivity(100%) and specificity(100%). Those results indicate PE reliably distinguished between whispers and phonation. The results also suggest that PE may provide a useful tool for studying the laryngeal source.

• Resources Recycling
• /
• v.23 no.6
• /
• pp.22-29
• /
• 2014

Recycling process of iron should be developed for efficient recovery of neodymium (Nd), rare metal, from acid-leaching solution of Nd magnet. In this study, $FeCl_3$ solution as iron source was used for preparation of iron nano particles with the condition of various factors, such as, reductant, and surfactant. $Na_4P_2O_7$ and Polyvinylpyrrolidone (PVP) as surfactants, $NaBH_4$ as reductant, and palladium chloride ($PdCl_2$) as a nucleation seed were used. Iron powder was analyzed by using XRD, SEM for measuring shape and size. Iron nano particles were prepared at the ratio of 1:5 (Fe (III) : $NaBH_4$). Size and shape of iron particles were round-form and 50 ~ 100 nm size. Zeta-potential of iron at the 100 mg/L of $Na_4P_2O_7$ was negative value, which was good for dispersion of metal particle. When $Na_4P_2O_7$ (100 mg/L), PVP($FeCl_3:PVP$ = 1 : 4, w/w) and Pd($FeCl_3:PdCl_2$ = 1 : 0.001, w/w) were used, iron nano particles which were round-shape, well-dispersed and near 100 nm-sized range. In this condition, $FeCl_3$ solution changed with spent Nd leachate solution, and then it is possible to be made round-formed iron nano particles at pH 9 and at the reaction bath over 20 L which is not include any surfactant.

• Child Health Nursing Research
• /
• v.8 no.2
• /
• pp.152-163
• /
• 2002

This study was done to provide basic data to develop smoking prevention and non-smoking education program. Questionnaire were collected from 438 male, 474 female middle school students at Chunchon, Kwangwon-do from Sep 2, 2000 to Feb 28, 2001. The Questionnaire used to measure subjects' knowledge and attitude about smoking was Guideline for the content of tobacco smoking surveys of the general population by WHO. The collected data were analyzed by SPSS-Win program. The results were as follows. 1.The average score of knowledge about smoking of subjects was 57.01 on the basis of 100. 2. The average score of attitude about smoking of subjects was 63.54 on the basis of 100. 3. In knowledge about smoking, there were statistically significant difference according to subjects' grade(F=3.218, p=.041), thinking about smoking behavior(F=3.424, p=.017), harmfulness of smoking(F=17.202, p=.000), present drinking(F=3.555, p=.029) and in attitude about smoking, there were statisti cally significant difference according to subjects' grade(F=20.520, p=.000), sex(t= -5.073, p=.000), mother's smoking(t= -2.405, p=.035), brother's smoking(t= -5.022, p=.000), mother's schooling(F= 3.730, p=.024), having smoking friend or not (t=-9.357, p=.000), subjects' smoking experience (t=-12.363, p=.000), present smoking(F= 76.643, p=.000), quantity of smoking(F= 6.808, p=.001), period of stop smoking(F= 4.685, p=.004), beginning time of smoking (F=2.286, p=.049), thinking about smoking behavior(F=17.933, p=.000), harmfulness of smoking(F=58.360, p=.000), present drinking (F=58.071, p=.000). 4. There were significant relationship between subjects' knowledge and attitude about smoking(r=.469, p=.000).

• Korean journal of food and cookery science
• /
• v.31 no.4
• /
• pp.510-514
• /
• 2015

Various parts of Kkujippong (Cudrania tricuspidata Bureau) tree (leaves, stems, roots, and fruit) were evaluated to determine their properties. The general components of Kkujippong tree were fat 1.3-5.9 g /100 g, protein 6.3-18.7 g /100 g, and ash 2.8-9.0 g /100 g. The fiber content of the stem was the highest amount at 69.2 g/100 g, followed by protein in the roots (49.9), leaves (45.5), and fruit (15.6). In addition, Kkujippong tree was found to contain high concentrations of several minerals (Ca, Fe, Mg, Na, P, Zn) in the leaves. The total polyphenol content was significantly higher in the leaves than in other areas at 571.3 mg% (p<0.05). Electron donating ability was also highest in the leaves at 83.55% (p<0.05).

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.32 no.4
• /
• pp.405-410
• /
• 2012

This study was carried out to investigate the effect of harvest stage of rape on nutritive values and quality of round baled rape silage in field of forage crops of Department of Animal Resources Development, National Institute of Animal Science, RDA. Rape was harvested at three different growth stages (flowering, milk and dough stage) and ensiled at each harvest stages. The content of moisture of rape increased with delayed harvest maturity. However, the content of moisture of rape was controlled by pre-wilting (24 hr. and 48 hr). The content of moisture in dough stage was similar to that of haylage. The content of crude protein in round baled rape silage increased with delayed harvest maturity, but the contents of acid detergent fiber, neutral detergent fiber and total digestible nutrient decreased. The pH in all rape silage ranged from 3.8 to 4.4 at three different harvest stages, and pH in dough stage was higher than that of flowering and milk stages (p<0.05). The content of lactic acid of all rape silage increased with delayed harvest maturity (p<0.05), but the content of acetic acid decreased (p<0.05). And then, flieg's score revealed that there was an increase in order; flowering stage (100) = milk stage (100) > ripen stage (88).

• Korean Journal of Microbiology
• /
• v.30 no.6
• /
• pp.528-532
• /
• 1992

The ATP-dependent protease. Clp P from Esehaichia coli has been increase the stahility with or without detergent as Triton X-100 and NP-40 in the Clp P. The C]p P proteolytic activity was remained to 0.1 M salt by $Na^{-1}$, $K^{+}$, $Li^{+}$ but was inhihited by $SO_4^{2}$. An active ATPase site in Clp A is required for A TP-dependent proteolysis by Clp protease as

• Journal of the Korean Society of Clothing and Textiles
• /
• v.33 no.11
• /
• pp.1696-1706
• /
• 2009

Nonwoven fabrics have been widely used in various fields that include household, industrial, agricultural, medical goods, especially in the automobile industry. In this study, eco-friendly fiber materials were developed and investigated as a substitute material for polyester fibers in nonwovens. To make plant fiber bundles, stems of Indian mallow (IM), and Kuzu vine (KV) were retted; in addition, the non-cellulose component was partially removed. Plant fiber bundles and polyester fibers (P) were blended and needle punched to produce nonwovens. Five kinds of nonwovens were manufactured: P100 (Polyester 100%), IM10 (IM 10% and Polyester 90%), IM20 (IM 20% and Polyester 80%), KV10 (KV 10% and Polyester 90%), and KV20 (KV 20% and Polyester 80%). The color values, surface appearance, tensile strength, elongation, tear strength, abrasion strength, flexstiffness, moisture regain, water or oil absorbency, and static electricity of manufactured nonwovens are investigated. As the blended ratios of IM or KV increased, the brightness of nonwovens decreased compared to that of polyester 100%. Tensile strength, tear strength, abrasion strength, and flexstiffness of IM10 as well as KV10 were higher than those of P100, IM20, and KV20, resulting from the influence of the structure and properties of nonwoven fibers. Moisture regain and water or oil absorbency increased, while static electricity decreased in proportion to the amount of plant fibers. IM or KV and polyester blended nonwovens showed improved properties over P100 that could be substituted for P100 as a novel material for textiles.

• The Journal of Internal Korean Medicine
• /
• v.18 no.2
• /
• pp.1-26
• /
• 1997

Chunggeumtang has been used in Korea for many centuries as a treatment for respiratory disease. The effect of Chunggeumtang on tracheal smooth muscle is not konwn. The purpose of the present study is to determine the effect of Chunggeumtang on histamine and acetylcholine induced tracheal smooth muscle contraction in rats and guinea pigs. Guinea pig(500g, male) and Sprague Dawley rats (250g, male) were killed by $CO_2$ exposure and a segment (8-10mm) of the thoracic trachea from each rat and guinea pig was cut into equal swegments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force diplacement transducers under 0.5g loading tension. The dose of histamine (His) and acetylcholine (Ach) which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for histamine and acetylcholine($10^{-7}{\sim}10^{-4}M$). Contractions evoked by His ($ED_{50}$) and Ach ($ED_{50}$) were inhibited significantly by Chunggeumtang. In guinea pig tracheal smooth muscle, the mean percent inhibition of acetylcholine induced contraction was $6.1%after\;30{\mu}l/ml$ Chunggeumtang, and 49.4% (p<0.01) after $100{\mu}l/ml$ Chunggeumtang. In rat tracheal smooth muscle, the mean percent inhibition of acetylcholine induced contraction was $6.7%\;after\;30{\mu}l/ml$ Chunggeumtang, and $54.2%\;(p<0.01)\;after\;100{\mu}l/ml$ Chunggeumtang. Also, in guinea pig tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was $30.6%\;(p<0.05)\;after\;30{\mu}l/ml$ Chunggeumtang, and $53.0%\;(p<0.01)\;after\;100{\mu}l/ml$ Chunggeumtang. In rat tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was $24.1%\;(p<0.05)\;after\;30{\mu}l/ml$ Chunggeumtang, and $55.3%\;(p<0.01)\;after\;100{\mu}l/ml$ Chunggeumtang. Propranolol and indomethacin($10^{-7}M$) slightly but significantly attenuated the inhibitory effects of Chunggeumtang. Following treatment with propranolol, the mean percent inhibition caused by $100{\mu}l/ml$ Chunggeumtang fell to 27.6% in guinea pig induced by acetylcholine contraction and by $100{\mu}l/ml$ Chunggeumtang fell to 28.7% (p<0.05) in rat induced by acetylcholine contraction and the mean percent inhibition caused by $100{\mu}l/ml$ Chunggeumtang fell to 16.2% in guinea pig induced by histamine contraction and by $100{\mu}l/ml$ Chunggeumtang fell to 28.7% (p<0.05) in rat induced by histamine contraction. Indomethacin, the mean percent inhibition caused by $100{\mu}l/ml$ Chunggeumtang fell to 20.0% in guinea pig induced by acetylcholine contraction and by $100{\mu}l/ml$ Chunggeumtang fell to 16.9% (p<0.05) in rat induced by acetylcholine contraction and the mean percent inhibition caused by $100{\mu}l/ml$ Chunggeumtang fell to 16.4% in guinea pig induced by histamine contraction and by $100{\mu}l/ml$ Chunggeumtang fell to 23.1% (p<0.05) in rat induced by histamine contraction. Methylene blue($10^{-7}M$) did not significantly alter the inhibitory effect of Chunggeumtang. Also, I could find the effects of Chunggeumtang and Chunggeumtanggamorphine on the tracheal smooth muscle in guinea pig and rat did not change significantly. These results indicate that Chunggeumtang can relax histamine and acetylcholine-induced contraction of guinea pig and rat tracheal smooth muscle, and that this inhibition involves sympathetic effects and the release of cyclooxygenase products.

• Korean Journal of Environmental Biology
• /
• v.30 no.2
• /
• pp.136-142
• /
• 2012

Acute toxicity test of heavy metal (Cd, Cu, Zn) were examined using the hatching rates of fertilized eggs in the oliver flounder, Paralichthys olivaceus. Eggs were exposed to Cd, Cu, Zn (0, 10, 100, 500, 1000, 2500, 5000 ppb) and then normal hatching rates were investigated after 48 h. The normal hatching rates in the control condition (not including Cd, Cu and Zn) were greater than 80%, but suddenly decreased with increasing of heavy metal concentrations. Cd, Cu and Zn reduced the normal hatching rates in concentration-dependent way and a significant reduction occurred at concentration grater than 1000, 100, 100 ppb, respectively. The ranking of heavy metal toxicity was Zn>Cu>Cd, with $EC_{50}$ values of 584, 1015 and 1282 ppb, respectively. The no-observed-effect-concentration (NOEC) and the lowest-observed-effect-concentration (LOEC) showed each 100 and 500 ppb of normal hatching rates in exposed to Cu and Zn. The NOEC and LOEC of normal hatching rates in Cd were 500 ppb and 1000 ppb, respectively. From these results, the normal hatching rates of P. olivaceus have toxic effect at greater than the 100 ppb concentrations in Cu, Zn and the 500 ppb concentrations in Cd in natural ecosystems. These results suggest that biological assay using the normal hatching rates of P. olivaceus are very useful test method for the acute toxicity assessment of a toxic substance as heavy metal in marine ecosystems.