• Proceedings of the Korean Sanitation Conference
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• 2006.11a
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• pp.33-42
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• 2006

We decided Miomotegawa river was the object of our investigation since it is one of the most important salmon rivers in Japan. A great number of salmonshave returned to the river, and it was expected to contain relatively lower cation concentrations since granite is widely distributed in the river catchment area. The concentration of calcium and magnesium were less than a half of that of other major rivers. The concentration of analyzed parameters indicating water quality effect on salmons, $NO_{3},\;SO_{4}\;and\;NH_{4}$, were 1.37, 4.08 and 0.01mg/l, respectively. Most parameters down stream were greater in concentration than in the upper stream.

• The korean journal of orthodontics
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• v.6 no.1
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• pp.47-54
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• 1976

This study was conducted to investigate the effects of multibanded orthodontic appliances on dental caries activity. The subjects consisted of 50 males and females with multibanded orthodontic appliance and the same number of caries free group. The following conclusions were obtained, 1. There was significant difference between the experimental group and control group in the tests of Snyder colorimetric test, acid :buffering capacity and oral glucose clearance test (at $5\%$ level of significance). 2. There was no significant difference between the experimental group and control group in the tests of unstimulated salivary flow fate, stimulated salivary flow rate and salivary viscosity test (at $5\%$ level of significance). 3. Dental caries activity was higher in experimental group than in control group.

• The Korean Journal of Ecology
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• v.13 no.2
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• pp.131-142
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• 1990

From July 1, 1985 to June 30, pH values of precipitation in Seoul area were average 5.1 and acid rain which was lower than pH 5.5 showed a frequence of 70.7%. Seasonal changes appeared in pH values of annual precipitation in Seoul. The pH patterns of spring and autumn were generally less acid than that of summer and winter, and snowfall pH was lower than rainfall. The beginning rainfall in Seoul was neutral because of alkali dust in the atmosphere. As times went on, rainfall pH was gradually low and after 1 to 2 hours, showed a steady state. On the surface soil precipitation was neutralized by soil buffering capacity.

• Journal of the Korean Wood Science and Technology
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• v.44 no.4
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• pp.505-514
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• 2016

To study mechanical properties of fiberglass reinforced wood-based composite (FRWC), fiberglass with a diameter of $20{\mu}m$ was selected to prepare test specimens. Mechanical properties of fiberglass reinforced wood-based composite were determined by three-point-bending test while its microstructure was characterizes by scanning electron microscopy (SEM). The results showed that mechanical properties of fiberglass reinforced wood-based composite were superior to that of the wood fiberboard based on the contrasting mechanical curves and the analysis of fracture mechanism. It is believed that the material design with this "sandwich" structure brings a unique buffering capacity of fiberglass into play in the composites. So the specimen did not produce a sudden fracture failure at high level of applied loads because it had a bearing ability. The SEM analysis showed that the working strength of PVAc adhesive was high; under a bearing force, it could properly transfer a load. In addition, glass fiber mesh and wood fiber board combined well.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.455-458
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• 2003

We investigated the leaching of elements from anthracite ashes by interactions with seawater. The results show that consumption rates of dissolved oxygen are 7.5 times greater in the seawater system than in the fresh water system and indicate that the differences in DO consumption rate may plat a role in regulating the element leaching from the coal ashes. It is revealed that seawater's pH buffering capacity is the most important factor that makes the leaching of elements and their chemical behaviors in the seawater system different from those in the fresh water environments. In overall, element leaching from the weathered ash is smaller than that from the fresh ash. However, the leaching of Si, Fe, Al, Mn, phosphate, and some other elements were independent of weathering. They were dependant only on the pH of the solutions.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.505-508
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• 2000

We discuss simulation results concerning the performance of the TCP protocol when running over high-speed HFC networks. Hybrid Fiber Coaxial are likely to provide fast and cost effective sup-port to a variety of applications including Video on demand, interactive computer games, and internet-type applications such as Webbrowsing, ftp, and telephony. Since most of these applications, use TCP as the transport later protocol, the key to their success largely depends on the effectiveness of the TCP protocol. In all simulation scenarios the TCP traffic is maxed with some background traffic whose level is taken as a variable parameter. Both the background traffic and TCP traffic are either unshaped, or shaped according to the GCRA algorithm. The effect of the background traffic on the TCP protocol performance is discussed varying the buffering capacity with nodes as well as the peak bit rate that each TCP connection is allowed to use.

• Journal of Environmental Science International
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• v.33 no.5
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• pp.323-332
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• 2024

Circulating hydroponic cultivation has the advantage of reducing soil and water pollution problems caused by discharge of fertilizer components because the nutrient solution is reused. However, cyclic hydroponic cultivation has a low biological buffering capacity and can cause outbreaks of infectious root pathogens. Therefore, it is necessary to develop technologies or disinfection systems to control them. This study used dielectric barrier discharge plasma, which generates various persistent oxidants, to treat Fusarium oxysporum f. sp., a pathogen that causes wilt disease. Batch and intermittent continuous inactivation experiments were conducted, and the results showed that the total residual oxidant was persistent in intermittent plasma treatment at intervals of 2-3 days, and F. oxysporum was treated efficiently. Intermittent plasma treatment did not inhibit the growth of tomatoes.

• Biomedical Science Letters
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• v.30 no.1
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• pp.17-23
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• 2024

In this study, the changes in occlusal strength and oral environment before and after the use of natural gargles containing cinnamon were confirmed. This study involved 42 adults aged 19 or older living in Busan from November 25 to December 2, 2023. Twenty-one people were randomly selected for each of the regular and natural gargles. In this study, the group using natural gargles confirmed an increase in saliva buffering power, a decrease in O'Leary index, and an increase in occlusal strength. Through this, it was confirmed that natural gargles containing cinnamon are helpful in improving the oral environment and occlusal strength.

• 한국체육학회지인문사회과학편
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• v.57 no.1
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• pp.405-419
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• 2018

This study of the Wholeness Program relevant to dementia behavior and verification of buffering effects. For the purpose of this, among those who were attending Day Care Centers belonging to Seniors Welfare Center of M1 and M2 located in Seoul. Among those who met all these requirements, 40 senior citizens were finally selected. After carrying out a preliminary test to the selected subjects, 20 elderly of Seniors Welfare Center of M1 were randomly placed as an experimental group, while other 20 people of Seniors Welfare Center of M2, as a control group. The Wholeness Program relevant to dementia behavior was carried out from March 14 to May 30 of 2016, for 12 weeks, twice a week. As for the measurement tool, this study depended on the Korean version of Mini Mental State Examination (MMSE-K), the Korean version of Modified Barthel Index (K-MBI) and the Korean version of Geriatric Depression Scale (GDS-K). While the elderly were participating in the Wholeness Program relevant to dementia behavior, they were measured two times in total, before and after the participation in dementia behavior. Based on SPSS-PC (version 21.0), firstly, independent t-test was carried out to understand the homogeneity between the experimental group and the control group. Secondly, matched-pair t-test was carried out between preliminary test and post-test to inquire into the effects of MMSE-K, K-MBI and GDS-K. Thirdly, ANOVA was conducted to confirm the variation (change amount) between preliminary test and post-test. According to the survey results, the Wholeness Program relevant to dementia behavior of the elderly shows overall effects in all spheres of changes of cognitive ability (MMSE-K), changes of physical capacity (K-MBI) and changes of depression level (GDS-K).

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.220-227
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• 2004

Phosphorus desorption study is essential to understanding P behavior in agricultural and environmental soils because phosphorus is considered as two different aspects, a plant nutrient versus an environmental contaminant. This study was conducted to determine soil P buffering power related to P desorption quantity intensity (Q/I) parameters, $Q_{max}$(an index of P release capacity) and $l_0$(an index of the intensity factor), and to investigate the characteristics of relationship between the P desorption Q/I parameters and the soil properties. Soil samples were prepared with treatments of 0 and $100mg\;P\;kg^{-1}$ applied as $KH_2PO_4$ solution. The P desorption Q/I curves were obtained by a procedure using anion exchange resin beads and described by an empirical equation ($Q=aI^{-1}+bln(I+1)+c$). The P desorption Q/I curves for the high available P (${\g}20mg\;kg^{-1}$ of Olsen P) soils were characteristic concave trends with or without soil P enrichment, whereas for the low available P (${\lt}20mg\;kg^{-1}$ of Olsen P) soils, the anticipated Q/I concave curves could not be obtained without a proper amount of P addition. When the soils were enriched in phosphates, the values of desorbed solid phase labile P and solution P, such as $Q_{max}$ and $I_0$ respectively, were increased, but the ratio of $Q_{max}$ versus $I_0$ was decreased. Thus, the slope of desorption Q/I curve represented as phosphorus buffering power, $|BP_0|$, is decreased. The $|BP_0|$ values of the high available P soils ranged between 48 and $61L\;kg^{-1}$ in the P untreated samples and between 18 and $44L\;kg^{-1}$ in the P enriched samples. Overall $|BP_0|$ values of both low and high available P soils treated with $l00mg\;P\;kg^{-1}$ ranged between 14 and $79L\;kg^{-1}$. The $Q_{max}$, values ranged between 71.4 and $173.1mg\;P\;kg^{-1}$, and the lo values ranged between 0.98 and $3.82mg\;P\;L^{-1}$ in the P enriched soils. The $Q_{max}$ and $I_0$ values that control the P buffering power may be not specifically related to a specific soil property, but those values were complicatedly related to soil pH, clay content, soil organic matter content, and lime. Also, phosphorus release activity, however, markedly depended on the desorbability of the applied P as well as the native labile P.