• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.115-119
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• 2008

Purpose: To compare the tentative and final addition, a combination chart of cross-grid and red green with the final addition prescribed in presbyopia were used in this study. Methods: The study subjects were 60 persons with presbyopia who were 41 to 60 years (mean: 51.7 years). Tentative addition were determined using red green chart (RG), cross-grid chart (CG) and the combination chart (red green cross-grid chart, RGCG) of the above two. And the final addition for a 40 cm working distance was determined for each subject by adjusting the tentative addition. Results: It was found that there were statistically significant differences of the final addition and the tentative addition between the each different test method. This result indicated that using the red-green cross-grid chart is the higher repeatability. Conclusions: This study shows that red green cross-grid chart (RGCG) seems to be get proper data for determining addition in presbyopes, and this method would be helpful in the diagnostic evaluation of addition in binocular vision testing.

• Journal of the Korea Institute of Building Construction
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• v.7 no.4
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• pp.117-124
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• 2007

Focused on the material-related aspect for enhancing the durability of concrete, the present study analyzed the effect of glycol ether admixture, which is a chemical admixture that can compact the structure of concrete by entraining air inside the concrete, on the basic physical properties and durability characteristic of the concrete. In analyzing the results of experiment, we examined the basic physical properties and durability characteristic of concrete according to addition rate based on OPC and selected the optimal addition rate. In addition, with the optimal addition rate, we added glycol ether admixture to concrete, which contained fly ash used as binder and high-performance water reducing agent for reducing the unit quantity, and examined changes in the characteristics of the concrete. According to the result, the optimal addition rate of glycol ether admixture was 3% of the unit quantity of cement, and the addition of binder and chemical admixture did not have a significant effect on unhardened concrete but reduced the air content. In addition, concrete showed resistance performance of around 30% to carbonation and around 40% to drying shrinkage. In addition, as for resistance to freezing and thawing, the relative dynamic modulus of elasticity was over around 85% through atmospheric curing. These performances prove the effect.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.8
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• pp.830-834
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• 2004

In this study, lead-free pirzoelectric ceramics were investigated for pressure sensor applications as a function of the amount of ${La}_2{O}_3$ addition at $Bi(Na, K)Ti{O}_3-SrTi{O}_3$system. With increasing the amount of addition, the density and dielectric constant increased up to 0.9 wt% ${La}_2{O}_3$ addition and decreased above 0.9 wt% ${La}_2{O}_3$addition. Electromechanical coupling factor( $K_{P}$) showed the maximum value at 0.2 wt% ${La}_2{O}_3$addition and decreased above 0.2 wt% ${La}_2{O}_3$ addition. Electromechanical coupling $factor{(K)}_P$, density, dielectric constant$(\varepsilon_\Gamma)$, piezoelectric constant$(d_33)$ and curie temperature$(T_C)$ showed optimum value of 0.40, 5.75 g/㎤, 768, 215 pC/N and 320 $^{\circ}C$ at 0.2 wt%${La}_2{O}_3$addition, respectively.

• Korean journal of food and cookery science
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• v.22 no.2 s.92
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• pp.140-146
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• 2006

The sensory characteristics of bread prepared with the addition of Angelica plant(Bakluncho) and Jujube(Daechu) powders were investigated The moisture, crude protein, as reducing sugar and vitamin C content of Angelica plant(Bakluncho) powders were 7.78%, 6.07%, 7.37%, 6.13% and 50.10 mg% respectively, and those of Jujube(Daechu) powders were 11.19%, 4.43%, 2.36%, 14.23% and 49.20 mg% respectively. Lightness value decreased but redness and yellowness values increased with increasing natural pigment powders content. The mechanical hardness of the bread decreased with the addition of 3% Angelica plant(Bakluncho) powders, but increased with the addition of 1% and 5% Angelica plant(Bakluncho) powders. The mechanical hardness of bread decreased with the addition of 1% and 3% Jujube(Daechu) powders, but increased with the addition of 5% Jujube(Daechu) powders. In sensory characteristics, the crust color, mb color, moistness and springiness decreased, but aroma and hardness increased with the increasing natural pigment powders content. The savory taste and overall quality of breads with 1% Angelica plant(Bakluncho) powders and 3% Jujube(Daechu) powders were higher than those of the control without my addition. A negative correlation was observed between Hunter's color value and overall quality of the bread prepared with addition of Angelica plant(Bakluncho) and Jujube(Daechu) powders.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.04b
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• pp.145-149
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• 2004

In this study, leed-free piezoelectric ceramics were investigated for pressure sensor applications as a function of the amount of $La_2O_3$ addition at BNKT system. With increasing amount of $La_2O_3$ addition, density and dielectric constant were increased up to 0.9wt% addition and decreased after 0.9wt% addition, electromechanical coupling factor$(k_p)$ and mechanical quality factor$(Q_m)$ showed the maximum values at 0.2wt% addition and decreased after 0.2wt% addition. The $k_p$, density, dielectric constant and $Q_m$ were showed the optimum values of 0.40, $5.71g/cm^3$, 768 and 118 at $La_2O_3$ 0.2wt% addition, respectively.

• Journal of the Korean Applied Science and Technology
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• v.14 no.1
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• pp.27-32
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• 1997

Furfurylidene acetophenone derivatives were synthesis, it was measured that nucleophilic addition made use of UV at a wide pH 1.0${\sim}$13.0 range in 30% dioxane-$H_2O$ solution, 25$^{\circ}C$. On the basis of general base catalysis, substitutent effect, confirmation of nucleophilic addition products, it was measured the reaction rate of furfurylidene acetophenone derivatives for the pH change. It may be concluded that a part was unrelated to pH and another part was in proportion to concentration of hydroxide ion: Above pH 10.0. sulfide anion adds to the double bond (Michael type addition), a part having no concern with pH, addition reaction to double bond is initiated by addition of neutral thiourea molecule. From the result of measurement the reaction rate, nucleophilic addition of furfurylidene acetophenone derivatives confirmed to the irreversible first order. Through measurement the substituent effect. It found that reaction rate was accelerated by electron attracting group. On the basis of these findings, nucleophilic addition of thiourea for the furfurylidene acetophenone derivative was proposed a fitting mechanisms.

• Current Optics and Photonics
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• v.1 no.5
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• pp.538-543
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• 2017

Progressive addition lenses (PAL) have very wide application in the modern glasses market. The unique progressive surface can make a lens have progressive refractive power, which can meet the human eye's different needs for distance-vision and near-vision. According to the national glasses fabrication standard, the difference between actual optical power after fabrication and nominal design value should be less than 0.1D over the lens effective area. The optical power distribution of PAL is determined directly by the surface. Consequently, the surface processing accuracy requirement is proposed. Beginning from the surface expressions of progressive addition lenses, the relationship equations between the surface sag and optical power distribution are derived. They are demonstrated through tolerance analysis and test of an example progressive addition lens with addition of 2.09D (5.46D-7.55D). The example addition surface is fabricated under given accuracy by a single-point diamond ultra-precision machine. The optical power of the PAL example is tested with a focal-meter after fabrication. The optical power addition difference between test result and design nominal value is 0.09D, which is less than 0.1D. The derived relationship between the surface error and optical power is verified from the PAL example simulation and test result. It can provide theoretical tolerance analysis proof for the PAL surface fabricating process.

• Journal of the Korean Society of Food Culture
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• v.20 no.3
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• pp.352-359
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• 2005

The red ginseng powder was added to Yackwa dough as ratio to 0%, 2%, 4%, 6% and 8%, respectively to know effect of red ginseng powder on Yackwa quality and preservation. The expansion, color, texture and preference characters were investigated at 0,2 and 4 weeks, respectively. The peroxide and acid value were also measured. The 4% addition increased greatly expansion rate. In color test, L value lowed at addition of red ginseng powder and at long storage period. the b value lowed as the addition was increased, but a value was not affected by the addition of red ginseng powder. In mechanical texture test, addition of red ginseng powder had a tendency to show low cohessivness, springness, gumminess while hardness increased. The springness, brittleness and cohessivness decreased while hardness increased at long storage period. In sensory test, surface color, bitterness and red ginseng flavor were recognized strong by addition of red ginseng powder but oily taste, crispness, softness and overall preference were weak. The surface color and red ginseng flavor were strong at long storage period but sweetness, softness and overall preference decreased, respectively. The peroxide value increased at long storage period and decreased after 6 week. The 2% and 4% addition showed lower peroxide value compared to other treatment. The acid value increased at early storage period, but did not change after 4 weeks.

• Korean Journal of Medicinal Crop Science
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• v.22 no.3
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• pp.188-195
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• 2014

This study was carried to investigate the effect of illite addition on the growth, bioactive components and volatile compounds of leaf on Saururus chinensis Baill cultivation in greenhouse. Illite addition on Saururus chinensis Baill cultivation resulted no significant effects on the aerial part. However, the root part was highest in 5% illite addition group. Crude oil and ash amount increased as illite additives was increased. Ca of inorganics and free sugars contents were highest in 5% and 20% illite addition, respectively. Hyperoside and isoquercetin of available component on leaf were highest in 5% illite addition group, 4.02mg/g and 4.31mg/g, respectively. The volatile compounds in Saururus chinensis Baill leaf cultured with illite addition amounts were isolated by solid-phase microextraction fiber (polydimethysiloxane $65{\mu}m$) and identifed by gas chromatogtaphy mass spectrometry. As the results, the 22 volatile compounds were identified from in Saururus chinensis Baill leaf and major volatile compounds were the ${\alpha}$-cadinol (18.50%), myristicin (16.46%), methyl-9-methyl-tetradecanoate (10.22%), and ${\gamma}$-muurolene (9.75%). Especially, the content of ${\alpha}$-cadinol was highest in 5% illite addition group and ${\gamma}$-muurolene on overall illite addition group was lower than no addition group.

• Journal of Educational Research in Mathematics
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• v.19 no.2
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• pp.307-319
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• 2009

Current school mathematics introduces addition/subtraction between natural numbers, fractions, decimal fractions, and square roots, step-by-step in order. It seems that, however, school mathematics focuses too much on learning the calculation method of addition/subtraction between each stages of numbers, to lead most of students to understand the coherent principle, lying in addition/subtraction algorithm between real numbers in all. This paper raises questions on this problematic approach of current school mathematics, in learning addition/subtraction. This paper intends to clarify the fact that, if we recognize addition/subtraction between numbers from the viewpoint of 'measuring' and 'common measure', as Dewey did when he argued that the psychological origin of the concept of number was measuring, then we could find some common principles of addition/subtraction operation, beyond the superficial differences among algorithms of addition/subtraction between each stages of numbers. At the end, this paper suggests the necessity of improving the methods of learning addition/subtraction in current school mathematics.