• Geophysics and Geophysical Exploration
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• v.14 no.4
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• pp.324-334
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• 2011

Seismic wave velocity change has been monitored due to the accumulation of micro-cracks by uniaxial loads on the rock samples from Seokmo Island with stepwise increase in 5 stages. After the load was applied up to 95% of UCS, P- and S-wave velocities varied in ranges of 0.9 ~ 18.3% and 2.8 ~ 14.8% of fresh rock sample velocities, respectively. Unlike seismic velocity of the dry rock samples that showed overall decreases after the loading, velocity changes of saturated rock samples were much more complicated. These seemed to be due to the mixture of two contradictory mechanisms; i.e. accumulation of micro-crack causes an increase in porosity and a decrease in wave velocity, while saturation causes an increase in wave velocity. Most of tested rocks showed a trend of velocity increase with low axial load and then velocity decrease at later stages. Starting stage of velocity decrease differs from samples to samples. After the failure of rock occurred, noticeable increases of porosity and decreases of wave velocity have been observed. It showed overall trend that the more the quartz contents and the lower the silicate, the higher the Young's modulus.

• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.316-322
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• 2010

The research attempted to develop a wood adhesive based on waste cooking oil, using ozonification technology for the chemical structure modification. The waste cooking oil (WCO) was reacted with $O_3$ for different times; 1 h, 2 h, and 3 h. The chemical structure modifications of the ozonized WCOs were examined by Fourier transform Infrared (FT-IR) spectrum. The FT-IR spectrum of WCO had an absorbance peak at 3,010 $cm^{-1}$ that was the characteristic peak of the unsaturated double bonds. As ozone treatment time increased, the peak of the double bond was disappeared and carboxyl peak appeared at 1,700 $cm^{-1}$. Especially, the double bond of 3 hrs-ozonized WCO was vanished almost. In results of the dry bonding strengths of the 3 hrs-ozonized WCO mixed with polymeric methylene diphenyl diisocyanate (pMDI) were the strengths of weight ratio of 3hrs-ozonized WCO : pMDI, 1 : 0.5, 8.08 kgf/$cm^2$, 1 : 0.75, 9.53 kgf/$cm^2$ 1 : 1, 44.16 kgf/$cm^2$, 1 : 2, 58.08 kgf/$cm^2$, 1 : 3, 61.41 kgf/$cm^2$, and 1 : 4, 46.95 kgf/$cm^2$. Therefore, it was found that the optimum equivalent ratio was formed at the ratio of 1 : 2 or 1 : 3. Under wetting the bonding strength of 1 : 3 ratio was appeared higher than that of 1 : 2 ratio, while the results obtained from hot-water and cyclic boiling shear test were similar.

• Korean journal of food and cookery science
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• v.11 no.5
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• pp.446-455
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• 1995

The nutritional properties of the Chol-Pyon were investigated with changing the materials (mugwort and pine leaves). In proximate composition, rice powder added mugwort and pine leaves showed the lligher con-tents of crude protein, crude lipid and crude ash than in rice powder. Ihe pH of rice powder, mugwort and pine leaves was 6.4, 6.8 and 3.5, respectively. The rice powder added pine leaves showed the lowest pH value. The content of the free sugar in raw materials for ChOl-PyOn preparation was 0.9% in rice powder, 0.3% in mugwort and 2.7％ in pine leaves. Eighteen kinds of amino acids were determined in raw materials for ChOl-fyOn preparation and their contents were 4.8% in mugwort, 4.2% in rice powder and 2.8% in pine leaves. The major minerals of raw materials for ChOl-PyOn preparation was 0.9％ increased in the order of K> Na > Mg > Ca in rice powder, Mg > K > Ca > Na in mugwort, and K > Ca > Mg > Na in pine leaves. Both of mugwort and pine leaves additives showed the higher contents of 8 kinds of minerals (Ca, Mg, K, Na, Mn, Fe, Cu, Zn) than in rice powder. In relation to changes in the texture of ChOl-PyOn, hardness, fracturability and adhesiveness at 25${\pm}$1$^{\circ}C$ were measured to be highest in white ChOl-PyOn. Cohesiveness was shown to be highest at 15％ in case of mugwort and 2.5％ in case of pine leaves. Elasticity was measured to be highest at 0.99 in case that 7.5% mugwort was added to raw materials for ChOl-PyOn. As a result of estimating the sensory qualities of the ChOl-PyOn prepared to which the additives were added in differing amounts, immediately after its preparation the mugwort additive of 7.5％ showed the superior sensory qualities Chol-PyOn (p < 0,01).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.2
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• pp.103-111
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• 1988

This study was carried out with two cultivars under two levels of pH and four levels of nitrogen fertilization in a field and nutri-culture experiments to obtain the information about the effects of pH and nitrogen fertilization on the growth and yield of soybean. Acidic condition suppressed the growth of soybean plants, and thus yield and yield components of soybean decreased under acidic condition. But they increased with increased nitrogen fertilization. Especially, these respones were more remarkable under acidic condition and in the variety Jangbaegkong. Grain yield of soybean were highly correlated with the content of allantoin and total nitrogen of soybean plants in the variety Jangbaegkong, but this was not in the variety Danyeobkong. The content of protein and fat of soybean seeds decreased under acidic condition, and more nitrogen fertilization increased the protein content, but decreased the fat content.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.6
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• pp.20-28
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• 2013

The purpose of this study was to compare the ultra-violet(UV) radiation under the landscaping shade facilities and tree with natural solar UV of the outdoor space at summer middays. The UVA+B and UVB were recorded every minute from the $20^{th}$ of June to the $26^{th}$ of September 2012 at a height of 1.1m above in the four different shading conditions, with fours same measuring system consisting of two couple of analog UVA+B sensor(220~370nm, Genicom's GUVA-T21GH) and UVB sensor(220~320nm, Genicom's GUVA-T21GH) and data acquisition systems(Comfile Tech.'s Moacon). Four different shading conditions were under an wooden shelter($W4.2m{\times}L4.2m{\times}H2.5m$), a polyester membrane structure ($W4.9m{\times}L4.9m{\times}H2.6m$), a Salix koreensis($H11{\times}B30$), and a brick-paved plot without any shading material. Based on the 648 records of 17 sunny days, the time serial difference of natural solar UVA+B and UVB for midday periods were analysed and compared, and statistical analysis about the difference between the four shading conditions was done based on the 2,052 records of daytime period from 10 A.M. to 4 P.M.. The major findings were as follows; 1. The average UVA+B under the wooden shelter, the membrane and the tree were $39{\mu}W/cm^2$(3.4%), $74{\mu}W/cm^2$(6.4%), $87{\mu}W/cm^2$(7.6%) respectively, while the solar UVA+B was $1.148{\mu}W/cm^2$. Which means those facilities and tree screened at least 93% of solar UV+B. 2. The average UVB under the wooden shelter, the membrane and the tree were $12{\mu}W/cm^2$(5.8%), $26{\mu}W/cm^2$(13%), $17{\mu}W/cm^2$(8.2%) respectively, while the solar UVB was $207{\mu}W/cm^2$. The membrane showed the highest level and the wooden shelter lowest. 3. According to the results of time serial analysis, the difference between the three shaded conditions around noon was very small, but the differences of early morning and late afternoon were apparently big. Which seems caused by the matter of the formal and structural characteristics of the shading facilities and tree, not by the shading materials itself. In summary, the performance of the four landscaping shade facilities and tree were very good at screening the solar UV at outdoor of summer middays, but poor at screening the lateral UV during early morning and late afternoon. Therefore, it can be apparently said that the more delicate design of shading facilities and big tree or forest to block the additional lateral UV, the more effective in conditioning the outdoor space reducing the useless or even harmful radiation for human activities.

• Restorative Dentistry and Endodontics
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• v.34 no.5
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• pp.406-414
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• 2009

The purpose of this study was to examine the effect of hydrogen peroxide at different application time and concentrations on the microtensile bond strength of resin restorations to the deep and the pulp chamber dentin. A conventional endodontic access cavity was prepared in each tooth, and then the teeth were randomly divided into 1 control group and 4 experimental groups as follows: Group 1, non treated; Group 2, with 20% Hydrogen peroxide ($H_2O_2$); Group 3, with 10% $H_2O_2$; Group 4, with 5% $H_2O_2$; Group 5, with 2.5% $H_2O_2$; the teeth of all groups except group 1 were treated for 20, 10, and 5min. The treated teeth were filled using a Superbond C&B (Sun medical Co., Shiga, Japan). Thereafter, the specimens were stored in distilled water at $37^{\circ}C$ for 24-hours and then sectioned into the deep and the chamber dentin. The microtensile bond strength values of each group were analyzed by 3-way ANOVA and Tukey post hoc test(p < 0.05). In this study, the microtensile bond strength of the deep dentin (D1) was significantly greater than that of the pulp chamber dentin (D2) in the all groups tested. The average of microtensile bond strength was decreased as the concentration and the application time of $H_2O_2$ were increased. Analysis showed significant correlation effect not only between the depth of the dentin and the concentration of $H_2O_2$ but also between the concentration of H202 and the application time(p < 0.05), while no significant difference existed among these three variables(p > 0.05). The higher $H_2O_2$ concentration, the more opened dentinal tubules under a scanning electron microscope(SEM) examination.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.827-833
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• 1995

Temperature distribution tests for a water cascading horizontal retort utilizing superheated water with overpressure as a heating medium were carried out under three different loading conditions, that is, empty(P-0), half-fully(P-3000) and fully(P-6000) loaded operating conditions. Tank volume and full loading capacity of sterilizer used for this study were about 5,900 liter and 1,140 kg(6000 pouches having 190 g weight each), respectively. Set point condition for sterilization was $122^{\circ}C$, 23 minutes and pressure was maintained in the range of $1.8{\sim}2.0\;kg/cm^2$ during sterilization. For each experiment, time-temperature data and F values were obtained from temperature microprocessor($F_0$ monitor). There were significant variations in the temperature distribution at different positions in the sterilizer. The temperature distribution was also affected by the pouch loading condition significantly. The application of the temperature distribution test to a product (retort pouched curry sauce) was conducted at the fully(P-6000) loading condition. Although heat transfer parameters($f_h\;and\;f_c$), and F values were varied with the position of sterilizer, sensory evaluation showed that the temperature distribution of the sterilizer used in this study didn't affect the quality of retorted curry sauce.

• Korean Journal of Poultry Science
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• v.28 no.3
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• pp.239-244
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• 2001

To examine the effects of feed additives on the expression of Perpheral blood cell surface molecules, phagocytosis and antigen specific antibody formation, broilers were randomly assigned to T$_1$, T$_2$, T$_3$, and T$_4$ groups. T$_1$ group was fed diet without any additives for 13 weeks, T$_2$ was fed diet with full fat flax, T$_3$ was fed diet with full fat flax containing $\alpha$-tocopherol, and T$_4$ was fed diet with full-fat flax containing $\alpha$-tocopherol and selenium. Since 5 weeks feeding the data were examined by luminometer. After 2 weeks adminstration of different feeding, although all treated groups (T$_2$, T$_3$, and T$_4$,) showed slightly increased chemiluminescence (CL) responses than T$_1$, this result was not significant. After 4 weeks feeding there was no significant increase of CL in the Phagocytes like neutrophils and macrophages of T$_2$ group compared to T$_1$. But phagocytes from T$_3$ and T$_4$ group showed in creased $O_2$- (6%, 18% respectively) as well as $H_2O$$_2$ (9.5% and 10.9%, respectively) induced CL responses. After 8 weeks feeding there was more than 50% increase $O_2$- induced CL in T$_3$ and T$_4$ group, but $H_2O$$_2$ induced CL responses in T$_3$ and T$_4$ group was slightly increased (6.6% and 9.3%, respectively).

• Culinary science and hospitality research
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• v.19 no.1
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• pp.244-251
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• 2013

The objective of this study was to determine the quality and sensory characteristics of Takju using different levels of seokim (0, 2, 4 and 6%(w/w)) at each fermentation step. The pH of Takju was dramatically reduced according to fermentation period after 1 day and total acidity was shown dramatically increased. The sugar content was increased sharply immediately after fermentation, and showed a tendency to decrease for 2-7 days. Reduced sugar content was increased by up to 2 days of fermentation, and then it was decreased to 2-7 days of fermentation. The alcohol content of all samples were increased until the end of fermentation period. After 7 days of Takju fermentation within Seokim, the addition of 0, 2, 4 and 6% seokim resulted in alcohol content of 10.3, 10.9, 12.1 and 12.2%, respectively. In the present study for the production of Takju, however, 4%(w/w) of seokim and the increase of alcohol content was low (maximum 12.2%, v/v). In Takju fermentation, the best content of seokim was 4%.

• Journal of Mushroom
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• v.8 no.1
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• pp.11-15
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• 2010

The word spawn is derived from an old French verb, espandre, meaning to spread out or expand. Spawn is also defined as "the mycelium of fungi, especially of mushrooms grown to be eaten, used for propagation". The effects of bag spawn to sawdust substrate on the growth of Pleurotus ostreatus were conducted. The duration of mycelial growth and days of pinhead formation of bag spawn(2.5kg) were 18~19days and 7~8days, whereas bottle spawn ($1,000m{\ell}$) was 18days and 6days, respectively. The yield of mushroom fruitbody was that bag spawn is 100~118g, bottle spawn is 95~115g. In economical analysis, bag spawn is increased to 50%, compared to bottle spawn in relative income.