• Journal of Soil and Groundwater Environment
• /
• v.14 no.1
• /
• pp.29-35
• /
• 2009

In this study, the effect of pH and temperature on the adsorption behavior of acid mine drainage (AMD) on coal mine drainage sludge (CMDS) has been investigated during the treatment of coal mine drainage (CMD) by electrical purification method. The pH$_{zero\;point\;charge}$ (pH$_{zpc}$) of CMDS was 5. The removal ratio of copper, zinc, cadmium, iron were increased according to the increase of pH value. The adsorption amount of copper showed 0.64 mg g$^{-1}$ sludge. It was independent of pH value. The adsorption amount of the other metals showed l.l times when pH was 3. The adsorption amount of chromium was a little bit increased at the pH value higher than 7 due to a small amount of the chromium was eluted as $Cr(OH)_6^{3-}$. The amount of metals' absorption were decreased according to temperature was increase at pH value was 3. The selectivity order was Cd>Fe > Zn > Cu. The amount of absorption showed q$_{max}$ Cu 2.747 mg g$^{-1}$ andZn 2.525 mg g$^{-1}$ when pH value higher than 5. It was independent of temperature.

• The Journal of Korean Academy of Prosthodontics
• /
• v.37 no.6
• /
• pp.756-766
• /
• 1999

This study was performed to evaluate effect on color and opacity of 3 different copy-milled In-Ceram cores by glass infiltration and porcelain veneering. Color was evaluated by the $CIEL^*a^*b^*$ readings were recorded with a Colorimeter, Color difference value(${\Delta}E^*_{ab}$) was calculated and opacity was represented by the contrast ratio. The variance of each color parameter ($L^*,\;a^*,\;b^*$), color difference value, and opacity change after glass-infiltrated and after veneered with porcelain was compared. Three experimental groups were fabricated as follows. Group 1 (Alumina core) 15 Alumina blanks was infiltrated with originally marketed glass (A1) and veneered with porcelain(A1) Group 2 (modified Alumina core) : 15 Alumina blanks was infiltrated with its associated glass(S11) and veneered with porcelain(A1) Group 3 (Spinell core) : 15 Spinell blanks was infiltrated with originally developed glass(S11) and veneered with porcelain(A1). The results were as follows: 1. After glass infiltration, $L^*$ value showed decrease, $a^*$ value showed decrease only group 1(p<0.001) and $b^*$ value showed increase on group 1, increase on group 2, 3(p<0.001). 2. After porcelain veneering, $L^*$ value showed decrease(p<0.001), $a^*$ value showed increase on group 1, decrease on group 2(p<0.05) and $b^*$ value showed decrease on group 1, increase on group 2, 3 (p<0.001). 3. ${\Delta}E^*_{ab}$ between before and after glass infiltration was more than 13.77, and between after glass infiltration and after porcelain veneering more than 19.63. 4. After glass infiltration and porcelain veneering, Alumina showed the lowest $L^*,\;a^*$ value and highest $b^*$ value among 3 different groups (p<0.05). ${\Delta}E^*_{ab}$ between group 1-2, 1-3 was higher than that of group 2-3. 5. After glass infiltration, opacity showed decrease, Group 1 had the highest opacity(p<0.05), but no significant differences between group 2 and 3. Above results suggest that glass infiltration and porcelain veneering effects on color and opacity of In-Ceram core, and that modified In-Ceram Alumina uses single crowns or bridges like In-Ceram Spinell.

• Journal of Korean society of Dental Hygiene
• /
• v.17 no.5
• /
• pp.853-864
• /
• 2017

Objectives: The purpose of the study was to investigate the influence of employment preparation behavior on motive to select dental hygiene as their major, and their work value among dental hygiene students. Methods: A self-reported questionnaire was completed by 444 dental hygiene students in South Korea from November 1 to 30, 2016. To analyze the data, the study used independent t-test, one way ANOVA, Pearson's correlation analysis, and regression analysis among others. Results: There were employment preparation behavior (2.9), major selection motive (3.1), and their work value (3.8) in subject. The higher student's grade is, the better prepared he or she for employment (p<0.001). Inner work value (p<0.01) and outer work value (p<0.05) were higher among females than males. Employment preparation behavior had significant positive effect on personal, social motive to select dental hygiene as their major, and their inner work value. Conclusions: Positive motivation to employment preparation behavior leads to major motive to select major, and their work value. It is necessary to consider study of diversified manners that can be fulfilled for employment preparation behavior.

• Korean journal of food and cookery science
• /
• v.32 no.4
• /
• pp.458-465
• /
• 2016

Purpose: Bokbunja (Rub coreanus Miquel), mulberry and blueberry have been reported to have powerful anti-antioxidant and anti-aging activities. The purpose of this study was to compare the quality characteristics and antioxidant activities of gravy sauce added with Bokbunja, mulberry and blueberry. Methods: Quality characteristics pH, brix, color and sensory characteristics of samples were evaluated. Antioxidant activities of samples were compared using total phenol, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities. Results: Mulberry juice showed significantly (p<0.05) higher values of pH and $^{\circ}Bx$ compared to Bokbunja and blueberry juice. Bokbunja juice also had significantly (p<0.05) higher value of Color-L value than mulberry and blueberry juice. The total phenol contents and ABTS cation radical scavenging activity of Bokbunja juice were 236.50 mgGAE/100 g and 61.66%, respectively, which were significantly (p<0.05) higher than those of blueberry and mulberry juice. pH value of gravy sauce added with mulberry (MBS) was 4.67, which was significantly higher than that of the control gravy sauce (GS) and gravy sauce added with Bokbunja (BJS) which had the lowest (p<0.05) pH value 4.33. $^{\circ}Bx$ of GS (13.50) was not significantly different from that of MBS and BBS. However, BJS showed the lowest (p<0.05) value $12.33^{\circ}Bx$. Total phenol contents and ABTS cation radical scavenging activity of BJS were 78.09 mgGAE/100 g and 14.47%, respectively, which were significantly (p<0.05) higher than those of MBS or BBS. Values of sensory characteristics color, sour aroma and sour flavor of BJS were significantly (p<0.05) higher value than those of other samples. Conclusion: Bokbunja juice and gravy sauce showed higher antioxidant activities and higher acceptance test compared to blueberry and mulberry. Thus, Bokbunja has the potential to be added to as high value products in the food industry.

• Bulletin of the Korean Mathematical Society
• /
• v.52 no.5
• /
• pp.1517-1533
• /
• 2015

In this paper, we prove the existence of at least three nontrivial solutions to nonlinear discrete boundary value problems $$\{^{-{\Delta}_{p,{\omega}}u(x)+V(x){\mid}u(x){\mid}^{q-2}u(x)=f(x,u(x)),x{\in}S,}_{u(x)=0,\;x{\in}{\partial}S}$$, involving the discrete p-Laplacian on simple, nite and connected graphs $\bar{S}(S{\cup}{\partial}S,E)$ with weight ${\omega}$, where 1 < q < p < ${\infty}$. The approach is based on a suitable combine of variational and truncations methods.

• Journal of the military operations research society of Korea
• /
• v.31 no.1
• /
• pp.122-129
• /
• 2005

In discrete red and black, you can stake any amount s in your possession, but the value of s takes positive integer value. Suppose your goal is N and your current fortune is ${\Large\;f},\;with\;O<{\Large\;f}. You win back your stake and as much more with probability p and lose your stake with probability, q=1-p. In this study, we consider optimum strategies for this game with the value of p less than ${\frac{1}{2}}$ where the house has the advantage over the player. It is shown that the optimum strategy at any ${\Large\;f}$ is the DBold strategy which is to play boldly in discrete red and black when $p<{\frac{1}{2}}$. And then, we perform the simulation study to show that this strategy, which is to bet as much as you can, is optimal in discrete case.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.7 no.1
• /
• pp.50-55
• /
• 1996

Acoustic analysis study was performed on 20 normal subjects by speaking nonsense syllables composed of Korean bilabial stops$(/P, P^{\star}, P^{h}/)$ and their preceding and/or following vowel /a/ (that is, $[pa, p^{\star}a, p^{h}a, apa, ap^{\star}a, ap^{h}a]$) with an ultraminiature pressure, sensor. in their mouths. Speech materials were phonated twice, once with a moderate voice, another time with a loud voice. The acoustic signal and intraoral pressure were recorded simultaneously on computer. By these procedures, we were to measure the intraoral pressure, closure duration and VOT of Korean bilabial stops, and to compare the values one another according to the intensity of phonation and the position of the target consonants. Intraoral pressure was measured by the peak intraoral pressure value of Its wave closure duration by the time interval between the onset of intraoral pressure build-up and the burst meaning the release of closure ; Voice onset time(VOT) on by the time interval between the burst and the onset or glottal vibration. Heavily aspirated bilabial stop consonant /$p^h$/ showed the highest intraoral pressure value, unaspirated /$p^{\star}$/, the second, slightly aspirated /P/, the lowest. The syllable initial bilabial stops showed higher intraoral pressure than word initial stops, and the value of loudly phonated consonants were higher than moderate consonants. The longest closure duration period was that of /$p^{\star}$/ and the shortest, /P/, and the duration was longer in word initial position and in the moderate voice. In VOT, the order of the longest to shortest was $/{p^h}/, /p/, /{p^\star}/$, and the value was shorer when the consonant was in intervocalic position and when it was phonated with a loud voice.

• Textile Coloration and Finishing
• /
• v.16 no.3
• /
• pp.1-7
• /
• 2004

To study the dyeability(K/S value) and surface color of silk fabrics dyed with Impatiens balsamina extract, its flower, leaf and stem, was extracted by water. This paper investigated some experiments with Impatiens balsamina extract under the various dyeing conditions such as dyeing temperature, dyeing time, repetition of dyeing, dyeing pH with silk fabrics. The results obtained were as follows. 1. It was found that it $\lambdamax$. of silk fabrics dyed with Impatiens balsamina extract was 260nm and its flower, leaf, stem and flowers(white, pink, violet) had same it $\lambdamax$ at 260nm. 2. K/S value was increased when dyeing temperature, repetition of dyeing and time was higher, value of munsell of silk fabrics dyed with Impatiens balsamina extract was yellow-red. dyeing temperature, repetition of dyeing and time was higher, shifted to longer wavelength side. 3. pH added acetic acid was colored reddish yellow-red, but pH added alum was colored yellowish yellow-red in silk fabrics dyed with Impatiens balsamina extract and repetition of dyeing was increased the dye-uptake.

• Proceedings of the KIEE Conference
• /
• 2003.11c
• /
• pp.789-792
• /
• 2003

pMOSFET having 10 ${\mu}um$ thickness Gd layer has been tested to be used as a slow neutron sensor. The total thermal neutron cross section for the Gd is 47,000 barns and the cross section value drops rapidly with increasing neutron energy. When slow neutrons are incident to the Gd layer, the conversion electrons are emitted by the neutron absorption process. The conversion electrons generate electron-hole pairs in the $SiO_2$ layer of the pMOSFET. The holes are easily trapped in Oxide and act as positive charge centers in the $SiO_2$ layer. Due to the induced positive charges, the threshold turn-on voltage of the pMOSFET is changed. We have found that the voltage change is proportional to the accumulated slow neutron dose, therefore the pMOSFET having a Gd nuclear reaction layer can be used for a slow neutron dosimeter. The Gd-pMOSFET were tested at HANARO neutron beam port and $^{60}CO$ irradiation facility to investigate slow neutron response and gamma response respectively. Also the pMOSFET without Gd layer were tested at same conditions to compare the characteristics to the Gd-pMOSFET. From the result, we have concluded that the Gd-pMOSFET is very sensitive to the slow neutron and can be used as a slow neutron dosimeter. It can also be used in a mixed radiation field by subtracting the voltage change value of a pMOSFET without Gd from the value of the Gd-pMOSFET.

• Food Science of Animal Resources
• /
• v.35 no.5
• /
• pp.646-652
• /
• 2015

The beef forequarter muscle comprises approximately 52% of carcass weight. The objective of this study was to evaluate the physiochemical characteristics and meat color from forequarter muscle of Holstein steers. Fifteen forequarter muscles were trimmed of external connective tissue and fat. An experimental group of eight Holstein steers was assessed using meat color, water-holding capacity, drip loss, and Warner-Bratzler shear force value at the same quality grade. The M. omotransversarius (0.45 kg) had the highest (p<0.05) lightness (L*) value, whereas the M. teres major (0.4 kg) and M. triceps brachii (caput laterale) (0.52 kg) had the lowest (p<0.05) values. The M. semispanitus capitus (1.48 kg), which is a neck muscle, had the highest values for both redness (a*) and yellowness (b*), whereas the lowest (p<0.05) values were for the M. teres major. The M. omotransversarius, M. latissimus dorsi (1.68 kg), and M. rhomboideus (1.2 kg) were ranked high (p<0.05) in water-holding capacity. The drip loss value was the highest for the M. longissimus dorsi thoracis (p<0.05; 1.86 kg), while the M. infraspinatus (2.28 kg), M. supraspinatus (1.38 kg), M. brachiocephalicus (1.01 kg), and M. pectoralis superficialis (1.18 kg) had the lowest (p<0.05). The Warner-Bratzler shear force value indicated that the M. pectoralis profundus (3.39 kg), M. omotransversarius, and M. brachiocephalicus were the toughest (p<0.05), whereas the M. subscapularis (0.86 kg), M. longissimus dorsi thoracis, M. teres major, and M. infraspinatus were the most tender cuts (p<0.05). Here, muscle type explained most of the variability in the forequarter physiochemical characteristics. Thus, our findings suggest that these muscle profile data will allow for more informed decisions when selecting individual muscles to produce value-added products from Holstein steers.