• Journal of Biosystems Engineering
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• v.4 no.1
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• pp.1-23
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• 1979

The use of barley seeder attached to rotary tiller in the rural area has a significant meaning not only for the solution of labor peak season, but also for the increase of land utilization efficiency. The facts that presently being used barley seeders are all based on the mechanical principles of the reverse rotation, center drive and are all using forward rotating tine, which is used to be easily and heavily worn out when it rotates reversely, raise problem of recommending them to rural area in Korea. Therefore, the main objective of the study was to develop new type of rotary tine attachable to barley seeders. To attain the objective the following approaches were applied. (1) The kinematic analysis of reverse rotating barley seeders. (2) The studies on the soil bin and artificial soil. (3) The comparative experiment on the power requirement of prototype tine. The results obtained from the studies are summarized as follow: 1. The kinematic analysis of barley seeder attached to rotary tiller: The following results were obtained from the kinematic analysis for deriving general formulae of the motion and velocity characterizing the rotary tine of barley seeders presently being used by farmers. a) The position vector (P) of edge point (P) in the rotary tine of reverse rotating, center drive was obtained by the following formula. $$P=(vt+Rcos wt)i+Rsin wt j+ \{ Rcos \theta r sin \alpha cos (wt- \beta +\theta r) +Rsin \theta r sin \alpha sin (wt-\beta + \theta r) \} lk $$ b) The velocity of edge point $(P^')$ of reverse rotating, center drive rotary tine was obtained by the following formula. $$(P^')=(V-wR sin wt)i+(w\cdot Rcoswt)j + \{ -w\cdot Rcos \theta r\cdot sin \alpha \cdot sin (wt-\beta +\theta r) + w\cdot Rsin \theta r\cdot sin \alpha \cdot cos (wt- \beta + \theta r \} k $$ c) In order to reduce the power requirement of rotary tine, the angle between holder and edge point was desired to be reduced. d) In order to reduce the power requirement, the edge point of rotary tine should be moved from the angle at the begining of cutting to center line of machine, and the additional cutting width should be also reduced. 2. The studies on the soil bin and artificial soil: In order to measure the power requirement of various cutting tines under the same physical condition of soil, the indoor experiments Viere conducted by filling soil bin with artificially made soil similar to the common paddy soil and the results were as follows: a) When the rolling frequencies$(x)$ of the artificial soil were increased, the densIty$(Y)$ was also increased as follows: $$y=1.073200 +0.070780x - 0.002263x^2 (g/cm^3)$$ b) The absolute hardness $(Y)$ of soil had following relationship with the rolling frequencies$(x)$ and were increased as the rolling frequencies were increased. $$Y=37.74 - \frac {0.64 + 0.17x-0. 0054x^2} {(3.36-0.17x + 0.0054x^2)^3} (kg/cm^3)$$ c) The density of soil had significant effect on the cohesion and angle of internal friction of soil. For instance, the soil with density of 1.6 to 1.75 had equivalent density of sandy loam soil with 29.5% of natural soil moisture content. d) The coefficient of kinetiic friction of iron plate on artificial soil was 0.31 to 0.41 and was comparable with that of the natural soil. e) When the pulling speed of soil bin was the 2nd forward speed of power tiller, the rpm of driving shaft of rotary was similar to that of power tiller, soil bin apparatus is indicating the good indoor tester. 3. The comparative experiment on the power requirement of prototype tine of reverse rotating rotary: According to the preliminary test of rotary tine developed with various degrees of angle between holder and edge pcint due to the kinematic analysis, comparative test between prototype rotary tine with $30 ^\circ $ and $10 ^\circ$ of it and presently being used rotary tine was carried out 2nd the results were as follows: a) The total cutting torque was low when the angle between holder and edge point was reduced. b) $\theta r$ (angle between holder and edge point) of rotary tine seemed to be one: of the factors maximizing the increase of torque. c) As the angle between holder and edge point ($\theta r$) of rotary tine was $30 ^\circ $ rather than $45 ^\circ $, the angle of rotation during cutting soil was reduced and the total cutting torque was accordingly reduced about 10%, and the reduction efficiency of total cutting torque was low when the angle between holder and edge point ($\theta r$) of rotary tine was $10 ^\circ $, which indicates that the proper angle between holder and edge point of rotary tine should be larger than $10 ^\circ $ and smaller than $30 ^\circ $ . From above results, it could be concluded that the use of the prototype rotary tine which reduced the angle between holder and edge point to $30 ^\circ $, insted of $45 ^\circ $, is disirable not only decreasing the power requirements, but also increasing the durabie hour of it. Also forward researches are needed, WIlich determine the optimum tilted angle of rotary brocket, and rearrangement of the rotary tine on the rotary boss.

• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.349-353
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• 2013

This study was performed to evaluate the bactericidal efficacy of Fumagari OPP$^{(R)}$, fumigation disinfectant, containing 20% ortho-phenylphenol against Staphylococcus aureus (S. aureus). In this research, efficacy test of fumigant against S. aureus was carried out according to French standard NF T 72-281. S. aureus working culture suspension number (N value), all of the colony numbers on the carriers exposed with the fumigant (n1, n2, and n3), the number of bacterial test suspentions by pour plate method (N1), the number of bacterial test suspentions by filter membrane method (N2) and the mean number of bacteria recovered on the control-carriers (T value) were obtained from the preliminary test. In addition, the reduction number of S. aureus exposed with the fumigant (d value) was calculated using T value, the mean number of bacteria in recovery solution (n'1) and the mean number of bacteria on carriers plated in agar (n'2). N value was $4.0{\times}10^8$ CFU/mL, and n1, n2, and n3 were higher than 0.5N1, 0.5N2 and 0.5N1, respectively. Additionally, T value was $3.4{\times}10^6$ CFU/mL. In the bactericidal effect of the fumigant, the d value was 6.43 logCFU/mL. According to the French standard for the fumigant, the d value for the effective bactericidal fumigant should be over than 5 logCFU/mL. The results indicated that Fumagari OPP$^{(R)}$ had an effective bactericidal activity against S. aureus, then the fumigant can be applied to disinfect food materials and kitchen appliances contaminated with pathogenic bacteria.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.2
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• pp.70-80
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• 2003

We report the first direct measurement of $CO_2$ flux over Kwangneung broadleaf deciduous forest, one of the tower flux sites in KoFlux network. Eddy covariance system was installed on a 30 m tower along with other meteorological instruments from June to August in 2002. Although the study site was non-ideal (with valley-like terrain), turbulence characteristics from limited wind directions (i.e., 90$\pm$45$^{\circ}$) was not significantly different from those obtained at simple, homogeneous terrains with an ideal fetch. Despite very low rate of data retrieval, preliminary results from our analysis are encouraging and worthy of further investigation. Ignoring the role of advection terms, the averaged net ecosystem exchange (NEE) of $CO_2$ ranged from -1.2 to 0.7 mg m$^{-2}$ s$^{-1}$ from June to August in 2002. The effect of weak turbulence on nocturnal NEE was examined in terms of friction velocity (u*) along with the estimation of storage term. The effect of low uf u* NEE was obvious with a threshold value of about 0.2 m s$^{-1}$ . The contribution of storage term to nocturnal NEE was insignificant; suggesting that the $CO_2$ stored within the forest canopy at night was probably removed by the drainage flow along the hilly terrain. This could be also an artifact of uncertainty in calculations of storage term based on a single-level concentration. The hyperbolic light response curves explained ＞80% of variation in the observed NEE, indicating that $CO_2$ exchange at the site was notably light-dependent. Such a relationship can be used effectively in filling up the missing gaps in NEE data through the season. Finally, a simple scaling analysis based on a linear flow model suggested that advection might play a significant role in NEE evaluation at this site.

• Journal of dental hygiene science
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• v.13 no.4
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• pp.493-500
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• 2013

The study aims to determine the status of oral health of mental illness patients and establish the preliminary data. The examinations and questionnaire survey were done 92 psychiatric patients to measure sociodemographic characteristics, decayed, missing and filled teeth (DMFT) index, patient hygiene performance (PHP) index, community periodontal index of treatment need (CPITN). Result of the missing teeth index in the state of oral health was higher in the hospital group (6.42) while the filled teeth index was higher in the center group (4.78). In the DMFT index, mental illness patients were higher than the national sample. The oral health status of medical aid recipients was poorer as the subjects were older and less educated (p<0.05). The PHP index was 3.41, close to the bad oral hygiene state. The hospital group (81.7%) required higher need for periodontal treatment. The periodontal health state was much poorer especially when the subject was in the age of 40's and 60's, received less education, and had no family (p<0.05). $CPITN_3$ was higher in the hospital group (13.3%) than the national sample (5.7%). The mental illness patients were socially vulnerable, therefore oral health care program should be needed and age, education level, health insurance type, presence of family and other factors needs to be considered in this approach.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.4
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• pp.325-334
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• 2008

The standard prestressed concrete I-girder bridge (PSC I-girder bridge) is one of the most prevalent types for small and medium bridges in Korea. When determining the member forces in a section to assess the safety of girder in this type of bridge, the general practice is to use the simplified practical equations or the live load distribution factors proposed in design standards rather than the precise analysis through the finite element method or so. Meanwhile, the live load distribution factors currently used in Korean design practice are just a reflection of overseas research results or design standards without alterations. Therefore, it is necessary to develop an equation of the live load distribution factors fit for the design conditions of Korea, considering the standardized section of standard PSC I-girder bridges and the design strength of concrete. In this study, to develop an equation of the live load distribution factors, a parametric analysis and sensitivity analysis were carried out on the parameters such as width of bridge, span length, girder spacing, width of traffic lane, etc. As a result, the major variables to determine the size of distribution factors were girder spacing, overhang length and span length in case of external girders. For internal adjacent girders, the determinant factors were girder spacing, overhang length, span length and width of bridge. For internal girders, the factors were girder spacing, width of bridge and span length. Then, an equation of live load distribution factors was developed through the multiple linear regression analysis on the results of parametric analysis. When the actual practice engineers design a bridge with the equation of live load distribution factors developed here, they will determine the design of member forces ensuring the appropriate safety rate more easily. Moreover, in the preliminary design, this model is expected to save much time for the repetitive design to improve the structural efficiency of PSC I-girder bridges.

• Journal of Veterinary Clinics
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• v.22 no.3
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• pp.202-205
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• 2005

The present study was made in order to clarify the anti-emetic effect by needle-acupuncture (AP), injection-AP and moxibustion in xylazine - induced vomiting of dogs. Twelve mongrel dogs (4 months to 5 year old, 2 to 4 kg of body weight), eleven mongrel dogs (4 months to 5 years old, 2 to 10 kg of body weight) and twelve mongrel dogs (4 months to 1 year old, 2 to 4 kg of body weight) were used for clarification of anti-emetic effect by needle-AP, injection-AP and moxibustion, respectively. The experimental animals were devided into control(6 heads), BL-21(6 heads), CV-12(6 heads) and BL-21+CV-12(6 heads) groups using total 6 dogs with vomiting selected in preliminary experiment, respectively in needle-AP treatment. In addition, the experimental dogs were divided into control (11 heads), BL-21 (6 heads) and CV-12(6 heads) groups using 11 dogs, respectively in injection-AP treatment. In moxibustion treatment the experimental dogs were divided into control (6 heads), BL-21(6 heads) and CV-12(6 heads) groups using 6 dogs, respectively. Five days after the experiment of one group was finished, the other group was examined in each experiment. Acupuncture needle was maintained for 20 minutes in needle-AP treatment. Metoclopramide was used in injection-AP treatment. Commercial moxa was used in moxibustion treatment. Vomiting was induced by intramuscular injection with $2{\%}$ xylazine 20 minutes after treatments of needle-AP, injection-AP and moxibustion, respectively. The vomiting rates of BL-21($33.3{\%}$), CV-12($50{\%}$) and BL-21+CV-12($33.3{\%}$) were lower than that of control($66.7{\%}$) and vomiting times of experimental groups were similar to that of control in needle-AP treatment. The vomiting rates of BL-21 ($0{\%}$) and CV-12($16.4{\%}$) were lower than that of control($66.7{\%}$) and the vomiting time of CV-12 group was similar to that of control group in injection-AP treatment. The vomiting rates of BL-21($33.3{\%}$) and CV-12($33.3{\%}$) were lower than that of control ($66.7{\%}$) and vomiting times of experimental group were similar to that of control group in moxibustion treatment. In conclusion, it was considered that needle-AP, metoclopramide injection-AP and moxibustion at BL-21 and CV-12 were effective for anti-emesis in xylazine induced vomiting of dogs and metoclopramide injection-AP was the most effective method for anti-emesis among them.

• Journal of Life Science
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• v.20 no.3
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• pp.381-387
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• 2010

To find offspring of Jeju Black cattle (JBC) produced by embryo transfer (ET) and artificial insemination (AI), a molecular genetic study was carried out in candidate cattle populations collected from cattle farms in Jeju Island, Korea. The genetic marker set was composed of 11 ISAG microsatellite (MS) markers, 11 SAES MS markers selected by our preliminary analysis for population diversity of JBC and two major coat color related genes: MC1R and ASIP. The results showed a combined non-exclusion probability for first parent (NE-P1) that was higher than that recommended by ISAG (above 0.9995), and a combined non-exclusion probability for sib identity of $5.3{\times}10^{-10}$. Parentage analysis showed that the cases identified the candidate's father only (77.0%), mother only (54.0%), and both parents (40.5%) in the candidate offspring population. The ET and AI calves were identified as 14.7% in the in vitro fertilized eggs provided and 32.4% in total population, respectively. However, the result from ISAG marker analysis showed 3 identical allele-combinations in 7 calves, and that from ISAG/SAES MS marker combination also showed 1 identical allele-combination in 2 calves. Data from MS and coat-color gene analyses provided information for complete identification of all animals tested. Because the present JBC population was mostly bred using small nuclear founders through bioengineering techniques such as AI and ET, the genetic diversity levels obtained from MS analysis in the JBC population were relatively lower than those of other cattle populations, including Hanwoo. The results suggested that the more efficient marker combinations, including coat color related genotypes, should be studied and used for constructing a system for identification and molecular breeding of JBC as well.

• Korean Journal of Plant Resources
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• v.28 no.5
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• pp.574-581
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• 2015

This study describes a preliminary evaluation of the anti-inflammatory activity of Acrosorium yendoi Yamada extracts. A. yendoi Yamada was extracted using 80% ethanol and then fractionated sequentially with n-hexane, ethyl acetate and butanol. To screen for anti-inflammatory agents effectively, we first examined the inhibitory effect of 80% EtOH extract and solvent fractions of A. yendoi Yamada on the production of pro-inflammatory factors and cytokines stimulated with lipopolysaccharide. In addition, we examined the inhibitory effect of 80% EtOH extract and solvent fractions of A. yendoi Yamada on pro-inflammatory mediators (NO, iNOS, PGE₂, and COX-2) in RAW 264.7 cells. In the sequential fractions of n-hexane and EtOAc inhibited the NO and PGE₂ production and the protein level of iNOS and COX-2, and protein expression of pro-inflammatory cytokines (TNF-α, and IL-6). These results suggest that A. yendoi Yamada may have significant effects on inflammatory factors and may be provided as possible anti-inflammatory therapeutic seaweed.

• The Korean Journal of Food And Nutrition
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• v.28 no.4
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• pp.594-601
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• 2015

In the present study, the total content of polyphenols and flavonoids, the antioxidant activities, and cytotoxic effects of the ethanol extracts from different parts of Taraxacum coreanum Nakai were investigated for their use as functional foods. The extract yields of the flower, leaf, and root were $32.15{\pm}3.21%$, $31.63{\pm}0.63%$, and $27.48{\pm}2.47%$, respectively. Total polyphenol and flavonoid content of the flower extract were $61.29{\pm}2.11mg/g$ and $46.11{\pm}1.88mg/g$, respectively, which were much higher than those of any other plant parts. The antioxidant activities of the flower, leaf, and root extracts were $89.99{\pm}2.83%$, $85.29{\pm}2.22%$, and $37.88{\pm}2.34%$, respectively, at a concentration of 1.0 mg/mL. Cell cytotoxicity effects of AGS (human gastric carcinoma), HCT116 (human colon carcinoma), and A549 (human pulmonary carcinoma) cells were the highest in the flower extract, with values of $62.85{\pm}4.63%$, $69.89{\pm}3.44%$, and $85.72{\pm}4.17%$, respectively, at a concentration of 400 mg/kg. Both the antioxidant activities and cytotoxic effects of the ethanol extracts from all the parts of the T. coreanum Nakai increased dose-dependently. These results provide preliminary data for the development of T. coreanum Nakai as an edible functional food material.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.2
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• pp.149-160
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• 2007

KoFlux Gwangneung Supersite comprises complex topography and diverse vegetation types (and structures), which necessitate complementary multi-disciplinary measurements to understand energy and matter exchange. Here, we report the results of this ongoing research with special focuses on carbon/water budgets in Gwangneung forest, implications of inter-dependency between water and carbon cycles, and the importance of hydrology in carbon cycling under monsoon climate. Comprehensive biometric and chamber measurements indicated the mean annual net ecosystem productivity (NEP) of this forest to be ${\sim}2.6\;t\;C\;ha^{-1}y^{-1}$. In conjunction with the tower flux measurement, the preliminary carbon budget suggests the Gwangneung forest to be an important sink for atmospheric $CO_2$. The catchment scale water budget indicated that $30\sim40%$ of annual precipitation was apportioned to evapotranspiration (ET). The growing season average of the water use efficiency (WUE), determined from leaf carbon isotope ratios of representative tree species, was about $12{\mu}mol\;CO_2/mmol\;H_2O$ with noticeable seasonal variations. Such information on ET and WUE can be used to constrain the catchment scale carbon uptake. Inter-annual variations in tree ring growth and soil respiration rates correlated with the magnitude and the pattern of precipitation during the growing season, which requires further investigation of the effect of a monsoon climate on the catchment carbon cycle. Additionally, we examine whether structural and functional units exist in this catchment by characterizing the spatial heterogeneity of the study site, which will provide the linkage between different spatial and temporal scale measurements.