• 한국초지조사료학회지
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• 제8권1호
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• pp.1-7
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• 1988

This experiment was carried out to determine the effect of grazing and cutting system in the seven different seed mixture plots on the dry matter yield and botanical composition from October 1983 to November 1986 at 200m above the sea level in Cheju. The results obtained are summarized as follows: 1. Dry matter yield was increased more cutting system than that of grazing system during the first and second harvest year (P<0.01), but at the third harvest year grazed plot was increased (P<0.05). 2. Three-year average dry matter yield tended to be relatively higher with tall fescue mixture plots (T4 and T7) than without tall fescue mixture plots. 3. In botanical composition of the seed mixtures, orchardgrass was observed to be more dominate in cutting system, while perennial ryegrass was increased in grazed plots. 4. Tall fescue was dominated about 70-80% at the third harvest year, in the plot of both grazing and cutting system. 5. The percentage of ladino clover was slightly increased in grazed plot compared with cutting plots. However those of alfalfa and red clover were not influenced by grazing and cutting system.

• 한국산학기술학회논문지
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• 제12권3호
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• pp.1452-1457
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• 2011

실리카흄과 이산화티타늄을 건식 및 습식방식에 의해 나노화하여 시멘트 모르타르의 강도특성실험을 수행하였다. 실험변수는 건식 및 습식 방식으로 제조된 혼화재를 각각 5,10,15,20%의 첨가율로 하였다. 그 결과 실리카흄과 이산화티타늄을 사용했을 때의 시멘트 모르타르 강도 특성이 유사하게 나타났으며 건식과 습식 혼화재의 비교에서는 습식 혼화재를 사용했을 때가 더 큰 강도 특성을 보였다.

• 펄프종이기술
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• 제36권3호
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• pp.35-43
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• 2004

Reduction of fresh water consumption and effluent discharge provide diverse advantages in raw materials and energy savings. Papermaking system closure, however, reduces the efficiency of additives, decreases retention and dewatering, and causes many other Problems in papermaking. Accumulation of inorganic and organic substances in the process white water is the prime cause of these problems. Understanding of the accumulation phenomena of the detrimental substances in the papermaking process is of great importance for papermaking system closure. In this study a process simulation method was employed to analyze the accumulation phenomena of anionic starch in the process white water as the reuse rate of dry broke and pick up of surface sizing agent is increased. Steady state simulation studies were carried out based on the model developed in previous study. The variation of dissolved starch concentration in each process unit was monitored as a function of reuse rate of dry broke and surface sizing agent pick up rate. The result showed that dissolved starch concentration Increased as reuse rate of dry broke and surface sizing agent pick up rate was increased.

• 한국재료학회지
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• 제14권10호
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• pp.743-748
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• 2004

Modified Ni/YSZ cermets for high temperature electrolysis were synthesized by the direct ball milling of Ni and YSZ powder. The ball milling was carried out in dry process and in ethanol with varying milling time. While the dry-milling decreased the average size from 65 to $80{\mu}m$, the wet-milling decreased the average size down to $10{\mu}m$. In addition, very fine particles less than $0.1{\mu}m$ were observed in the wet-milling condition. The subsequent process of cold-pressing and sintering at $900^{\circ}C$ for 2 h did not affect the particle size of dry-milled powder. The electrical conductivity of the dry-milled Ni/YSZ cermet showed the value of $5{\times}10^{2}\;S/cm$ and this value was increased to $1.4{\times}10^{4}\;S/cm$ after the sintering at $900^{\circ}C$ for 2 h.

• The Korean Journal of Ecology
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• 제23권2호
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• pp.181-185
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• 2000

This study was carried out to see whether Gastrophysa viridula (Degeer) (Coleoptera : Chrysomelidae) could be used as a biological control agent for Rumex obtusifolius L., with human manipulation of the beetle population. The study was consisted of three experimental sets : Wet-Dry experiment (the wet weight Vs dry weight relationship of Rumex obtusifolius L.), Greenhouse feeding experiment, and Field experiment. There was a significant correlation between the total wet and dry weight of Rumex obtusifolius as follows : Total dry weight : -0.23542+ (0.17514${\times}$Total wet weight) ($R^2$=0.9317, p=0.047, T=16.927 (dF=21)). In the Greenhouse feeding experiment, the result was very promising. The relationship between the density unit of the beetles and the growth of the plant is given below (20 day) : Plant growth =105.8+(-34.4${\times}$Density unit) ($R^2$=0.76, p=0.13). A repeated introduction of the beetle population into the field vegetation of R. obtusifolius from April to October is suggested to see the beetle's grazing ability on the plant. This study shows that the potential grazing power of the beetle on Rumex obtusifolius was enough to defoliate the plants, but it was able to recover from its root reserves. The practical question remains as to whether repeated additions (by man) of the beetles to Rumex obtusifolius could eliminate them.

• Corrosion Science and Technology
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• 제2권4호
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• pp.165-170
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• 2003

Atmospheric corrosion behaviors of Zn, Zn-5%Al and Zn-55%A l coated steels have been investigated under cyclic wet-dry environments containing chloride ions. The wet-dry cycle was carried out by alternate exposure to immersion in 0.5 M (or 0.05 M) NaCl solutions and drying at $25^{\circ}C$ and 60 %RH. The polarization resistance $R_p$ and solution resistance $R_s$ were monitored by AC impedance technique. From the obtained $1/R_p$ and $1/R_s$ values, the corrosion rate of the coatings and the Time of Wetness (TOW) were estimated, respectively. Effects of chloride ions and TOW on the corrosion rates of Zn, Zn-5%Al, Zn-55%Al coatings and appearance of red rust (onset of underlying steel corrosion) under wet-dry cycles are discussed on the basis of the corrosion monitoring data.

• Structural Engineering and Mechanics
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• 제65권2호
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• pp.203-211
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• 2018

This paper introduces the development process of NCC(New Concrete Cutting) system and analyzes first verification test. Based on the first verification test results, some problems of NCC system have been newly modified. We carry out the second verification test. We tried to verify cutting performance and dust control efficiency of NCC system through the cutting test of concrete bridge piers. In particular, this verification test strives to solve the problem of concrete dust, which is the biggest problem of dry cutting method. The remaining dust problems in cutting section tried to solve through this verification test. This verification test of the NCC system shows that the dust problem of dry cutting method is closely controlled and solved. In conclusion, the proposed NCC method is superior to the dry cutting method in all aspects, including cutting performance, dust vacuum efficiency and cooling effect. The proposed NCC system is believed to be able to provide eco-friendly cutting technology to various industries, such as the removal of the SOC structures and the dismantling of nuclear plants, which have recently become a hot issue in the field of concrete cutting.

• 대한한의학회지
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• 제28권2호통권70호
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• pp.13-21
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• 2007

Objective : Halitosis, or bad breath, is a common concern for many people. The aim of this study was to investigate clinical characteristics of halitosis patients and correlation with their various associated elements. Methods: We surveyed 169 halitosis patients by reviewing questionnaires from the Halitosis Clinic in the Hospital of Oriental Medicine, Kyunghee University from January 2004 to March 2006. The questionnaires contained various items including sex, age, history of smoking and alcohol intake, duration of symptoms in a week, time and condition of severe halitosis, suggestive origin of halitosis, taste abnormality, oral hygiene, self-assessed halitosis severity, dry mouth, postnasal drip, tonsillolith, globus pharyngeus, reflux sensation, too much gas and Winkel tongue coating index. Volatile sulfur compounds were measured with a $Halimeter^{\circledR}$. Results : The halitosis patients actively carried out management methods such as non-smoking, moderation in drink, teeth brushing and tongue scraping in order to decrease their oral malodor. Tongue coating significantly affected the $Halimeter^{\circledR}$ reading score, and tongue coating and dry mouth significantly affected self-assessed halitosis severity. Conclusions: Our results suggest that tongue coating and dry mouth should be treated to improve satisfaction in halitosis patients.

• Journal of the Korean Wood Science and Technology
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• 제16권1호
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• pp.45-54
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• 1988

This study was carried out to investigate the fiber length, fiber width and fiber thickness on the longitudinal direction by the parts of culm and also specific gravity in air dry, dyna.mic mechanical properties and internal frictions by the internode and the node in Phyllostachys bambusoides Phyllostachys nigra var. henonis and Phllostachys edulis which were grown in Korea. The results obtained were as follows; 1. The variations of fiber length and fiber width on the longitudinal direction had a tendency to increase slightly from the butt and then to decrease toward the top. but there was not a definite variation for fiber thickness according to the parts of culm. 2. The specific gravity in air dry of internode was increased from the butt toward the top, but the specific gravity in air dry of node was not correlations with the parts of culm. 3. Dynamic Young's modulus of internode on the longitudinal direction was increased according to the heights of culms within each species, and there were in order of P. edulis P. nigra var. henonis and P. bambusoides. 4. Correation coefficients between the specific gravity and the dynamic Young's modulus were 0.837 in P. bambusoides 0.871 in P. nigra var. henonis and 0.935 in P. edulis and there was also highly significant for dynamic Young's modulus between the specific gravities in air dry. 5. There were not correlations between the internal frictions and the parts of internode.

• 한국작물학회지
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• 제32권4호
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• pp.425-430
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• 1987

남부지방에서 황금의 직파재배와 육묘이직 재배시 적정 파종기와 정식기를 구명하고자 시험을 실시한 결과는 다음과 같다. 1. 출현은 황금의 파종기나 정식기가 빠를수록 늦어지고 늦어질수록 단축되는 경향으로 출현일수와 파종기 및 정식기간에는 고도의 부의 상관이 인정되었다. 2. 생육은 직파재배에 있어서 4월 15 일의 파종이 초장과 경태가 크고 분지수가 많아서 가장 양호하였으며, 육묘이식재배는 4월 1일 정식이 가장 좋은 경향이었다. 3 수량은 직파담배에서는 4월 15일 파종, 육묘 이식재배는 4월 1일 정식에서 근장이 가장 크고, 건근중이 무거워 수량이 증수되었다. 4 주요 형질간 상관을 보면 수량은 초장과 분지수, 그리고 근장과 정의 상관 관계를 나타내었고, 근장은 건근중과 건경중에 고도의 정의 상관 관계가 인정되었다.