• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.5
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• pp.57-65
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• 2022

This study investigated the electromechanical response of smart ultra-high performance fiber reinforced concretes (S-UHPFRCs) under flexural loading to evaluate the self-sensing capacity of S-UHPFRCs in both tension and compression region. The electrical resistivity of S-UHPFRCs under flexural continuously changed even after first cracking due to the deflection-hardening behavior of S-UHPFRCs with the appearance of multiple microcracks. As the equivalent bending stress increased, the electrical resistivity of S-UHPFRCs decreased from 976.57 to 514.05 kΩ(47.0%) as the equivalent bending stress increased in compression region, and that did from 979.61 to 682.28 kΩ(30.4%) in tension region. The stress sensitivity coefficient of S-UHPFRCs in compression and tension region was 1.709 and 1.098 %/MPa, respectively. And, the deflection sensitivity coefficient of S-UHPFRCs in compression region(30.06 %/mm) was higher than that in tension region(19.72 %/mm). The initial deflection sensing capacity of S-UHPFRCs was almost 50% of each deflection sensitivity coefficient, and it was confirmed that it has an excellent sensing capacity for the initial deflection. Although both stress- and deflection-sensing capacity of S-UHPFRCs under flexural were higher in compression region than in tension region, S-UHPFRCs are sufficient as a self-sensing material to be applied to the construction field.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.2
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• pp.198-203
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• 2008

This study was conducted to compare the effects of feeding high protein and low energy milk replacer (HPR; CP 25%, ME 3.6 Mcal/kg DM) with low protein and high energy milk replacer (HPR; CP 21%, ME 4.2 Mcal/kg DM) on feed consumption, body weight (BW) gain, health and selected blood metabolites in Holstein calves during the pre-weaning period. At each feeding, each milk replacer (MR) was prepared by mixing 0.125 kg of dry MR in 1L of warm ($60^{\circ}C$) water. The calves were fed either HPR (n = 10) or HER (n = 10) using mobile plastic bottles fitted with soft rubber nipples. All calves received 1.8L diluted MR at each feeding 3 times daily during the first 4 weeks of age; feeding frequency was reduced to 2 times daily for the next 2 weeks of age and then to once daily during the last week of the experiment. Jugular blood was sampled in calves at day 7, 14, 21, 35 and 49 of age to enumerate selected metabolites. Daily MR, starter and hay intake during the pre-weaning period were similar in calves fed HPR and HER. Consumption of starter, MGH and total DM steadily increased with the age of calves. Final BW, daily BW gain and feed efficiency of calves were not affected by treatments. Serum glucose, cholesterol, creatinine were decreased (p<0.05) and blood urea N was increased (p<0.05) in calves fed HER or HPR as they grew older. Serum glucose, total protein and albumin concentrations in calves were not affected by treatments. Serum GPT and GOT concentrations were higher (p<0.05) in calves on HPR than on HER. Scouring score, days scoured, respiratory score, rectal temperature and general appearance were similar in calves fed HPR and HER. Poor general appearance (dullness and droopy ears) of calves fed either HPR or HER reflected nutritional insufficiency and stress. In conclusion, energy and protein concentrations in MR did not affect feed intake and BW gain in Holstein calves during the pre-weaning period. Poor general appearance and lower BW gain of calves compared to those reported in the literature for milk fed calves prompt a demand for further research to improve the daily nutrient supply to MR-fed calves.

• The Korean Journal of Community Living Science
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• v.25 no.4
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• pp.557-566
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• 2014

This study examines he trend in the development of protective clothing for pesticide spraying based on materials with domestic patents and proposes pesticide protection clothing using a cooling blower unit effective for reducing heat stress in pesticide spraying. There was a total of 54 domestic patents on protective clothing related to pesticide spraying, reflecting a sharp increase based on the increasing demand for protective clothing since 2000. Protective clothing with a lower level of heat stress as the core technology accounted for 35.2% of these patents, and recent years have witnessed the increased development of protective clothing supplying cold air to the interior of the clothing through a separate device. However, this may cause some inconvenience in the activity of farmers. Therefore, this study proposes a lightweight cooling blower unit that does not hinder the user's appearance and activity. In the cooling blower unit, contaminated air from outside is purified through a filter and cools down as it passes a cooling device with refrigerant in the copper pipe. This chilled air is supplied to the interior of the clothing through a bidirectional inhaling blower. The proposed protective clothing is an overall with raglan sleeves. Its chill injection site has an area where the most conspicuous change in temperature is selected, and at the back, there is a large pocket for a cooling blower unit.

• Korean Journal of Oriental Medicine
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• v.3 no.1
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• pp.241-260
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• 1997

Effect of Jeongkicheonhyangtang and Kamijeongkicheonhyangtang have been experimentally studied. The results have been obtained as follows : 1. It is proved that analgecic effect on sample I group and sample II group are clearly decreased than control group. Thus, the statistically significant decrease is p<0.005. 2. It is proved that anti-inflammatory effect on sample I group and sample II group are decreased compare to control group. Thus, the statistically significant decrease of sample I group is p<0.05 in 30 and 60-minute, p<0.01 in 90-minute, and p<0.005 in 120 and 180-minute. And those of sample ll group is p<0.05 in 30 and 60-minute and p<0.005 in 90, 120 and 180-minute. 3. It is proved that appearance of gastric ulcer is decreased compare to the control group and the statistically significant decrease is p<0.05. 4. It is proved that plasma epinephrine contents of sample I and II group are clearly decreased compare to the Control Group and the statistically significant decrease is p<0.005. 5. It is proved that plasma norepinephrine contents of sample I group is drastically decreased compare to the control group and the statistically significant decrease is p<0.005. 6. It is proved that plasma dopamine contents of sample I and II group are decreased than the contort group and statistically significant decrease of the sample I group is p<0.005, and those of the sample II group is p<0.05. As the above mentioned results of experiment, It is belived that Jeongklcheonhyang and Kamijeongkicheonhyang have effect for stress.

• Atmosphere
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• v.18 no.2
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• pp.137-146
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• 2008

This study examines one thermal index, perceived temperature (PT), over the Korean Peninsula during 2007 summer. Heat/cold stress has been described using air temperature and humidity for warm seasons and air temperature and wind velocity in the cold conditions, while PT is based on a heat budget model of the human body that considers air temperature, humidity, wind velocity and radiation effect regardless of climates, regions and seasons. PT is higher about $4-5^{\circ}C$ than air temperature in the summer. Humidity increases PT, while wind tends to reduces PT possibly by evaporation of water vapor. The geographical distribution of summer PT indicates that the lowest PT happened in the east central region, with the appearance of the highest PT in the inland of southern region in Korea. Although the latitudinal trend shows that PT decreases northward, inland PT is higher than that of coastal region. Compared to the heat index or the discomfort index that considers air temperature and humidity, PT represents distinctive regional characteristics of thermal comfort. The distribution of PT shows that it may be a useful thermal index for the assessment of thermal comfort or stress region in the Korean Peninsula.

• Journal of Digital Convergence
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• v.20 no.1
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• pp.399-414
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• 2022

The purpose of this study was to test the structural model for the effect on abnormal eating behavior targeting 493 nurses. Results, The direct effects of variables affecting abnormal eating behavior were in the order of eating abstinence and socially imposed perfectionism, and these variables explained 85% of abnormal eating behavior. Explicit narcissism had a significant effect on abnormal eating behavior through socially imposed perfectionism and eating restraint, and sociocultural attitude toward appearance through eating restraint. In the multi-group moderating effect, the path coefficients between job stress and abnormal eating behavior, socially imposed perfectionism and abnormal eating behavior were different between groups. Therefore, it is necessary to find a way to lower the socially-imposed perfectionism and nursing intervention that can escape excessive eating abstinence.

• Journal of Korean Society of Steel Construction
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• v.19 no.6
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• pp.559-573
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• 2007

Orthotropic steel decks are manufactured by welding thin plates therefore it is inevitable that there are abundant works of welding process. On connection of transverse rib web, crossing point of longitudinal rib, transverse rib and deck plate and cut-out parts of transverse rib are the significant position of stress concentration because of out of plane and oil-canning deformation caused by longitudinal rib distortion with shear force and distortion. At the current research, the crossing point where the orthotropic steel decks's effect of improving fatigue performance are high, not placing scallop and diaphragm which have same plane with transverse rib placed inside of longitudinal rib at the same time, the reduce effects of stress concentration at the cut-out section and the crossing are high. Especially the installation of the diaphragm causing great effects based on research results to stress concentration appearance reduce effects at the cut-out section, putting radius of curvature of the diaphragm's top and bottom as a target, as a result of carrying out the parametric analysis an optimal diaphragm form that has great effects in fatigue performance came to a conclusion. Also based on optimal diaphragm form, an advantage of the diaphragm optimal setting position for improvement of the fatigue performance came to a conclusion.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.113-120
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• 2020

For the conservation of both Sericinus montela (vulnerable species by red book of Korea) and A. contorta, we investigated environmental factors affecting the growth and reproduction of Aristolochia contorta. We selected four A. contorta habitats at Gapyeong, Pyeongtaek, Cheongju, and Yeoju in Korea and surveyed community and habitat characteristics of companion species, herbivore appearance, support types, and soil physicochemical properties in July and October, 2018. Habitat environments and the growth and reproduction characteristics of A. contorta were different according to four habitats of different regions. In particular, the fastest growth speed and earliest flowering and fruiting were observed in Pyeongtaek. Growth of A. contorta in Cheongju and Yeoju were interrupted by aboveground damage from human disturbance. In this study, support types seemed to be important for growth speed of A. contorta. Flowering and fruiting timing were likely to be related to combined effects of soil cation contents and competitive and herbivore stresses. Therefore, providing effective support and reducing biological stress should be necessary for stable growth and proper flowering and fruiting timing of A. contorta. In addition, experimental evidence would be needed to figure out the effect of soil cation and biological stress on flowering and fruiting of A. contorta in detail.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.6 s.58
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• pp.192-203
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• 2009

In the new Seoul-Busan high speed railroad construction specially in area of city center passage the roadbed establishment is recommended the staibility for the existing subway tunnel segments of Busan subway 1st and 2nd lines regarding the appearance condition, a quality condition and the durability of the objective facility, and it evaluates the numerical analysis using MIDAS/GTS which leads the stability of the objective facility and investigatesd tunnels. Fundamental issues in tunneling under high groundwater table are discussed and the effect of groundwater on tunnel excavation was examined using a 3D stress-pore pressure coupled Finite-Element Method. Based on the results the interaction mechanism between the tunnelling and groundwater is identified. In the both of 1st and 2nd Line the maximum sinkage, unequal sinkage and the lining stress from numerical analysis are within permission and the damage degree is appearing to be disregarded. But it enforces necessary Pre-grouting in order to minimize an actual tunnel face conduct and when the tunnel is excavated it is also necessary to minimize the outflow possibility.

• Journal of the Korea Furniture Society
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• v.19 no.3
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• pp.193-202
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• 2008

In order to occupy educational furniture market that grows by the day and to meet demands for alternative product for the current market, this study took business features and productivity of Sinil Furniture Co into consideration, and developed computer desk for education by group, which is new among educational furniture. The scope of the study ranges from data research based on design process into creation of prototype. By improving the condition where, despite that electrically-powered computer desk for anti-theft system is high priced, it sees frequent malfunction, the study suggested low-priced, non- electrically-powered anti-theft system which has more solid structure. Furthermore, in order for the user to be more free and comfortable while studying on it, it differentiates from other products by locating PC main body to the back of the monitor and lowering it below the altitude of monitor to prevent it from interfering with studies. We've made the higher board of the desk in a soft curved-shape in order to lessen the stress from studying. And as space for the monitor's lower mount was decreased, we've put the lower mount below the higher board; so that lacking space can be recovered while functioning as anti-theft system. Moreover, we've covered the PC main body with steel cover so that it would add color and formal luxuriousness to the appearance of the desk. Considering ease of mobility and productivity, knock-down system was introduced.