• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1259-1266
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• 2018

Objective: This study was carried out to investigate the possible application of Broussonetia papyrifera (B. papyrifera) silage as a functional feeding stuff in dairy cattle. Methods: Seventy-two Holstein cows were divided into four groups randomly and allocated to 6 pens with 3 individuals in each group and fed the original total mixed ratio (TMR) in the dairy farm or the new TMR with 5%, 10%, and 15% B. papyrifera silage, separately. Feed intake were recorded, milk and blood samples were collected, and milk composition, blood metabolites and milk fatty acids composition were measure at the end of the experiment. Results: Dry matter intake of cows decreased when they fed on diet with B. papyrifera, but no differences were observed in body condition score, milk yield, milk protein and lactose, feed efficiency and serum metabolites between groups. Both 10% or 15% of B. papyrifera silage in the diet significantly increased the immunoglobulin A (IgA) and IgG in serum, 15% of B. papyrifera silage increased the content of serum catalase, superoxide dismutase, total antioxidant capacity, and decreased the content of 8-hydroxy-2'-deoxyguanosine. Furthermore, 10% or 15% of B. papyrifera silage resulted in a significant decrease in the milk somatic cell count, and increased the polyunsaturated fatty acids content in the milk. Conclusion: The diets with 10% to 15% of B. papyrifera silage might enhance the immune and antioxidant function of dairy cows and increase the polyunstaturated fatty acid concentration in the milk.

• The Journal of Korean Physical Therapy
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• v.11 no.3
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• pp.159-175
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• 1999

The purpose of this study lies in providing the basic materials for wrestlers' control of health and physical strength, the preventive, measure for injury during a practice or a game and the scientific training method for upgrading competitive power in a game. The result of analyzing the occurring tendency and therapeutical actions and attitude of sports injury, taking the 258 wrestlers from a high school, an university and pro-team as the object of study through a questioning sheet are like following. 1. Among every wrestlers' causes of injury, the main cause was a physical collision occupying $\50\%$, and an excessive training occupied $30\%$. on the contrary, the unsatisfied wrestler's cause of injury was a shortage of mental concentration and a burden of weight, occupying each $19\%$ and $17\%$. Therefore in order to prevent the injury, you should take care of especially in time of physical collision in a practice or a grme and prevent an excessive training. 2. The seasion with the most frequent occurrence of injury is the winter$(78\%)$, and in the spring and summer$(5.5\%)$, the frequency of occurrence of injury is very low. In the meantime, considering by occurring time, during a practice$(95\%)$ the injury occurs most frequently and during a game$(5\%)$ occure least frequently. Therefore, in order to reduce the injury, you should warm up sufficiently before the training and the practice and concentrate all of you attention and mind. 3. The injury occurs most highly in the afternoon hours occupying about $80\%$, and a little in the dawn and morning hours but in the contrary rarely in the night. 4. As the wrestler's injury type, the injury on muscles and tendons occupies the most to take $65\%$ of the whole injuries.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.1
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• pp.55-60
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• 2012

In order to investigate the effect of n-heptane mixing on PAH and soot formation, small amount of n-heptane has been mixed in counterflow ethylene diffusion flame. Laser-induced incandescene and laser-induced fluorescene techniques were employed to measure soot volume fraction and polycyclic aromatic hydrocarbon(PAH) concentration, respectively. Results showed that the mixing of n-heptane in ethylene diffusion flame produces more PAHs and soot than those of pure ethylene flame. However, signals of LIF for 20% n-heptane mixture flame were lower than that of pure ethylene flame. It can be considered that the enhancement of PAH and soot formation by the n-heptane mixing of ethylene can be explained by methyl($CH_3$) radical in the low temperature region. And it can be found that reaction rate of H radical for 10% n-heptane plays a crucial role for benzene formation.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.2
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• pp.171-177
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• 2014

A two-dimensional particle image velocimetry (2D PIV) system in a towing tank is employed to measure a wake field of a very large crude oil carrier model with rotating propeller in self propulsion condition, to identify characteristics of wake of a propeller working behind a ship. Phase-averaged and time-averaged flow fields are measured for a horizontal plane. Scale ratio of the model ship is 1/100 and Froude number is 0.142. By phase-averaging technique, trajectories of tip vortex and hub vortex are identified and characteristic secondary vortex distribution is observed in the hub vortex region. Propeller wake on the starboard side is more accelerated than that on the port side, due to the difference of inflow of propeller blades. The hub vortex trajectory tends to face the port side. With the fluctuation part of the phase-averaged velocity field, turbulent kinetic energy (TKE) is also derived. In the center of tip vortex and hub vortex region, high TKE concentration is observed. In addition, a time-averaged vector field is also measured and compared with phase-averaged vector field.

• Journal of the Korean Chemical Society
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• v.20 no.6
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• pp.486-493
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• 1976

The PVC mixed silver iodide pellet was prepared by means of the Infrared Pellet presser and the pellet was used as an indicating membrane electrode, to measure the potentials for various silver ion activities, ranging from $10^{-1}$ to $10^{-6}$ M. The potential responses to silver ion activities were linear and the slope was much close to Nernstian relation as compared with that of the pure silver iodide pellet membrane electrode and the PVC coated silver iodide pellet membrane electrode. The mechanical property and chemical durability of this electrode were found much better than the others. This electrode did not show significant response to the other except silver ion, but had good response to halide ions, i.e., iodide, chloride, bromide and cyanide ions, in the concentration range $10^{-1}$ to $10^{-6}$ M. This electrode could be used as an indicating electrode in potentiometric titrations of single halide ion and also halide mixture with standard solution of silver nitrate.

• Safety and Health at Work
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• v.3 no.2
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• pp.130-139
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• 2012

Objectives: The purpose of this study is to evaluate the tire manufacturing work environments extensively and to identify workers' exposure to hazardous substances in various work processes. Methods: Personal air sampling was conducted to measure polycyclic aromatic hydrocarbons, carbon disulfide, 1,3-butadiene, styrene, methyl isobutyl ketone, methylcyclohexane, formaldehyde, sulfur dioxide, and rubber fume in tire manufacturing plants using the National Institute for Occupational Safety Health Manual of Analytical Methods. Noise, carbon monoxide, and heat stress exposure were evaluated using direct reading instruments. Past concentrations of rubber fume were assessed using regression analysis of total particulate data from 2003 to 2007, after identifying the correlation between the concentration of total particulate and rubber fume. Results: Workers were exposed to rubber fume that exceeded 0.6 mg/$m^3$, the maximum exposure limit of the UK, in curing and production management processes. Forty-seven percent of workers were exposed to noise levels exceeding 85 dBA. Workers in the production management process were exposed to $28.1^{\circ}C$ (wet bulb globe temperature value, WBGT value) even when the outdoor atmosphere was $2.7^{\circ}C$ (WBGT value). Exposures to other substances were below the limit of detection or under a tenth of the threshold limit values given by the American Conference of Governmental Industrial Hygienists. Conclusion: To better classify exposure groups and to improve work environments, examining closely at rubber fume components and temperature as risk indicators in tire manufacturing is recommended.

• Safety and Health at Work
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• v.11 no.1
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• pp.109-117
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• 2020

Background: Ammonia and hydrogen sulfide are harmful gases generated during aerobic/anaerobic bacterial decomposition of livestock manure. We evaluated ammonia and hydrogen sulfide concentrations generated from workplaces at livestock farms and determined environmental factors influencing the gas concentrations. Methods: Five commercial swine farms and five poultry farms were selected for monitoring. Real-time monitors were used to measure the ammonia and hydrogen sulfide concentrations and environmental conditions during the manure-handling processes. Monitoring was conducted in the manure storage facility and composting facility. Information on the farm conditions was also collected through interview and walk-through survey. Results: The ammonia concentrations were significantly higher at the swine composting facilities (9.5-43.2 ppm) than at other manure-handling facilities at the swine and poultry farms, and high concentrations of hydrogen sulfide were identified during the manure agitation and mixing process at the swine manure storage facilities (6.9-19.5 ppm). At the poultry manure-handling facilities, the ammonia concentration was higher during the manure-handling processes (2.6-57.9 ppm), and very low hydrogen sulfide concentrations (0-3.4 ppm) were detected. The air temperature and relative humidity, volume of the facility, duration of manure storage, and the number of animals influenced the gas concentrations. Conclusion: A high level of hazardous gases was generated during manure handling, and some levels increased up to risk levels that can threaten workers' health and safety. Some of the farm operational factors were also found to influence the gas levels. By controlling and improving these factors, it would be possible to protect workers' safety and health from occupational risks.

• Plant Journal
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• v.4 no.2
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• pp.60-65
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• 2008

As the operating conditions in a supercritical oxidation reactor are set in high temperature with high pressure causing a reactor suffering from the harsh circumstances. It means the reactor adopts itself with Fe-Cr alloy in acidic atmosphere with low pH value and Ni alloy in basic atmosphere with high pH value due to its superior corrosion resistance. The study, whose target waster water is pertinent to the latter part, has selected Ni alloy such as ostenite type stainless steel 304 and 316, superstainless steel AL6XN, Inconel 625, MAT 21, and titanium Gr. 5 in order to measure corrosion resistance against those samples under the same conditions of temperature and pressure applied for a supercritical oxidation reactor. The result shows the identifiable difference in corrosion resistance by observing the surface states through a scanning probe microscope as well as measuring the weight loss through making the samples above deposited in wastewater for two-week and four-week stay. The purpose of this corrosion experiment is to identify the most corrosion-resistant material among sample species pre-selected according to pH concentration of wastewater in pursue of applying for a reactor exposed to the extreme corrosion environment. It is because such a reactor made of a verified material enables to safeguard a stable operation under the supercritical wastewater processing facility.

• Journal of Korean Society on Water Environment
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• v.32 no.5
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• pp.403-409
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• 2016

In this study, a TiO₂ nanotube was grown on a titanium plate by using anodic oxidation method for the evaluation of TiO₂ nanotube morphology. The TiO₂ nanotube was grown in an electrolyte containing ethylene glycol, 0.2 wt% of NH₄F and 2 vol% of H₂O. Applied voltage varied from 30 to 70 V and the morphology of the TiO₂ nanotube was observed. After anodization, a TiO₂ nanotube plate was immersed in 35℃ ethanol for 24 hours. Anatase and rutile crystal forms of TiO₂ nanoutbe were observed after annealing. 4-chrolobenzoic acid, a probe compound for OH radicals, was dissolved in H₂O in order to measure the OH radical. Liquid chromatography was used to check the concentration of the 4-chrolobenzoic acid. The OH radical generation by TiO₂ nanotube plate was proportionate to the length of the TiO₂ nanotube. Furthermore, when the number of TiO₂ nanotube plate increased, the OH radical generation increased as well.

• Journal of the Korean Wood Science and Technology
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• v.43 no.1
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• pp.96-103
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• 2015

The aim of this paper is to analyze combustion characteristics of treated woods by fire retardants which are prepared by several borate and phosphate compound solutions. The combustion characteristics for flame retardant treated wood were carried out using thermogravimetric analysis (TGA) to measure their combustion heat and flame retardant test using cone-calorimeter. The result of TGA and flame retardant test showed that single chemical solution affected the char forming and flame delay. The mixed retardants solutions was believed to be related to the efficacy and property of single chemical. The retention value and concentration of the retardants also affected the performance of fire retardant treated woods. The fire retardants FR1 and FR2 satisfied the requirement of The 3 Grade of Korean building codes.