• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.6
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• pp.850-854
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• 2014

Analyzing dynamic performance between pantograph and contact wire depends on mechanical and electrical conditions such as contact force, currents, aerodynamics of pantograph and tension of overhead contact wire. For the characteristic of dynamic performance between pantograph and overhead contact wire, various evaluation systems are used to measuring of the interaction of the contact line and the pantograph. Among the various methods, the contact force and percentage of arcing are intended to prove the safety and the quality of the current collection system on the train. However, these methods are only capable of measuring on the train which are installed measurement systems. Therefore in this paper, a track-side monitoring system was implemented to measure electrical characteristics from active overhead contact wire systems in order to constantly estimate current collection performance of railway operation. In addition, a method to analyze loss of contact phenomena was proposed. According to simulation results, the proposed system was capable of measuring abnormal electrical behavior of pantograph and contact wires on the track-side. The advantage of the proposed system is possible to detect loss of contact or any other electrical abnormalities of all types of trains within sections from sub to sub without the need to install any on-board equipment on trains.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.5
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• pp.671-683
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• 2005

Statement of problem: The most commonly reported problem associated with dental implant restoration is the loosening of the screws. Purpose: This study compared the efficacy of an implant system incorporating an anti-rotational locking sleeve(Anti-Rotating Inner Post Screw System(ARIPS-system)) with other, traditional implant systems as a means of minimizing vibration loosening. Materials and methods: Three implant systems were examined; the conventional external hex type, the ARIPS-system, and the internal taper type implant system 30 specimens(10 samples per group)were fabricated and each abutment screw was secured to the implant future with 32Ncm of torque force and loosening torque was measured using a Torque Gauge. The procedure was repeated 3 times, recording initial loosening torque each time. The re-tightened abutment screw was subjected to a cyclic load having a maximum forte of 200N and minimum of 20N at 2Hz over a period of 12,600 cycles. after which the loosening torque was measured. Measured values were calaulated for statistical analysis. Analysis of measured value was performed by 3 methods: (i) as a percentage average of the initial 3 loosening-torque values(initial loosening value) to the tightening torque of 32Ncm, (ii) as a percentage of the loosening torque value after a load of 200N(experimental value) to the initial loosening value, and (iii) as a percentage of the experimental value to the 32Ncm of tightening torque. The analyses shows the amount of initial loosening at the screw, loosening by repetitive load and the the final loosening value. Results: The results of this study were as follows (1) Percentage of initial loosening value to tightening-torque was increased in order of external hex, ARIPS-system and internal taper and all values between each groups showed statistical significance (p<0.05). (2) Percentage of experimental value to initial loosening value was increased in order of external hex, ARIPS-system and internal taper. Value of internal taper showed significant difference with those of external hex and ARIPS-system (p<0.05). (3) Percentage of experimental value to tightening torque was increased in order of external hex, ARIPS-system and internal taper and all values between each groups showed statistical significance (p<0.05). Conclusion: The results of the analysis of the final loosening level value, which are closely correlated to clinical use, show that the ARIPS-system can be a useful means of minimizing abutment screw loosening when compared to the external hex type system. Although further clinical studies need to be made, the ARIPS-system should be considered to maximize the long-term success of the implant prosthesis.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.261-269
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• 2008

This experiment was performed to investigate the anxiolytic-like effects of cyclopeptide fraction alkaloids of Zizyphi Spinosi Semen (CFAZ), by using the experimental paradigms of anxiety, and compared with those of a known anxiolytic, diazepam. CFAZ (8.0 mg/kg, p.o.) increased the percentage of time spent on the open arms and the number of open arms entries in the elevated plus-maze test, increased the number of head dips in the hole-board test, and increased the percentage of center zone ambulatory time in the open-field box. However, CFAZ has no effect on the locomotor activity, while diazepam (2.0 mg/kg, p.o.) significantly reduced locomotor activity. CFAZ did not influence the grip force in the grip strength meter test, either. From the molecular experiments, CFAZ increased chloride influx in cultured cerebellar granule cells. In addition, $GABA_A$ receptors $\gamma$-subunit were over-expressed by CFAZ in cultured cerebellar granule cells. It is concluded that CFAZ may have anxiolytic-like effects, and these effects may be mediated by $GABA_A$ receptors.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.3
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• pp.420-426
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• 2005

Effect of pasture finishing on $\alpha$-tocopherol and $\beta$-carotene concentrations, drip loss, cooking loss, Warner-Bratzler shear force, fatty acid composition, meat color and metmyoglobin percentage of m. longissimus thoracis of Japanese Shorthorn steers was studied. Japanese Shorthorn steers (n=8), fattened indoors with a concentrate-based diet until they were 19 months of age were divided into two groups of four steers. Steers of the concentrate-fed group were fattened indoors with a concentrate-based diet until they were slaughtered. Steers of the pasture-fed group were fattened on pasture until they were slaughtered. The $\alpha$-tocopherol and $\beta$-carotene concentrations in the muscle of the pasture-fed group were higher (p<0.05) than those of the concentrate-fed group. The drip loss of the muscle of the pasture-fed group was lower (p<0.05) than that of the concentrate-fed group. Compared with the concentrate-fed group, the concentration of peroxidisable lipids (fatty acids with three or more unsaturated bonds) in the muscle of the pasture-fed group was high (p<0.05). The metmyoglobin percentage during display of the muscle of the pasture-fed group was higher (p<0.05) than that of the concentrate-fed group. These results suggested that pasture finishing decreased drip loss of the beef but lowered meat color stability.

• International Journal of Computer Science & Network Security
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• v.23 no.8
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• pp.1-8
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• 2023

The artificial intelligence of robot is the weakness of digital intelligence of a person who able to train, self-realize and to develop competences, creative, professional and behavioral skills. A new methodology proposed for managing robots inside the mines using an electronic system designed for driving robots to injured people in seas, mines or wells who can not be reached by human force. This paper also explains the concept of managing and remote-controlling the process of searching and helping the injured. The user controls the robot through an application that receives all the reports that the robot sends from the injured person. The robot's tasks are to take a sample of the blood of the injured person, examine it, and measure the percentage of oxygen underground and send it to the user who directs the robot to pump a specific percentage of oxygen to the injured person. The user can also communicate with the person The patient and determine his condition through the camera connected to the robot equipped with headphones to communicate with the injured and the user can direct the camera of the robot and take x-rays from the injured.

• Animal Bioscience
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• v.34 no.5
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• pp.914-921
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• 2021

Objective: The objective of this study was to compare growth performance, carcass traits and meat quality in young bulls, steers and heifers produced by crossing Limousin bulls with Holstein-Friesian cows, fattened semi-intensively and slaughtered at 18 months of age. Methods: Thirty-one young calves were reared in a conventional production system, and were fed milk replacer, hay and concentrate. At 6 months of age, the animals were divided into groups based on gender, and were fed a total mixed ration composed of grass silage, concentrates I and II in a semi-intensive production system. At the end of the fattening period (18 months), the animals were slaughtered, carcass quality was evaluated, and samples of musculus longissimus thoracis were collected to determine the proximate composition and quality of meat. Results: Bulls were characterized by the highest percentage share of the most valuable cuts in the carcass, and three-rib sections from bull carcasses had the highest lean meat content with low intramuscular fat content (0.93%). No significant differences in carcass conformation, dressing percentage or the percentage share of round in the right half-carcass were found between bulls vs. steers and heifers. Heifers and steers had higher carcass fat content than bulls, which had a positive influence on the sensory properties of beef. In comparison with the meat of bulls, the meat of steers and heifers was characterized by more desirable physical properties and sensory attributes (water-holding capacity, shear force, color lightness, aroma, juiciness, tenderness, flavor). Conclusion: Under the semi-intensive production system, heifers and steers had higher carcass fat content than bulls, which had a positive effect on the sensory properties of beef. Bulls are better suited for intensive systems, which contribute to improving the quality of their meat. The results of this study may encourage producers to breed steers and heifers for beef.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.492-505
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• 2007

Statement of problem: An orthodontic miniscrew implant has been used as a skeletal anchorage for orthodontic treatment. However, any relation among the influence of the cortical bone, morphologic differences of orthodontic miniscrew implants and new bone formation hasn't been made clear yet. Purpose: The purpose of this study was to evaluate whether the orthodontic miniscrew implant could work as an intraoral skeletal anchorage immediately and stably for orthodontic treatment after insertion of it. Material and methods: Two types of orthodontic miniscrew implants were used in this experiment; tapered type and straight type. One hundred and sixty eight orthodontic miniscrew implants were inserted into the tibiae of 21 rabbits and sacrificed on 3, 7, 11, 14, 21 and 28days later after insertion of them to study removal torque values and histologic and histomorphometric analyses. Results: The results were as follows. 1. The removal torque values of the tapered type were higher than those of the straight type in all groups(p<0.05). 2. There wasn't any distinguishing differences between the tapered type and the straight type about the new bone formation percentage. 3. The removal torque values for both the tapered type and the straight type were gradually decreased at early stages of the test but started to increase at the 7 days group of the straight type and the 11 days group of the tapered type. 4. New bone formation percentage was increased gradually for both the tapered and the straight types as time passed(p<0.05). 5. It was found that the tapered type showed lower values in the cortical bone about both the maximum equilibratory stress distribution and the maximum principal stress distribution than the straight type in linear finite elements analysis. Conclusion: According to the research, the removal torque values were decreased at 7 days group of the tapered type and 11 days group of the straight type after the insertion of the orthodontic miniscrew implants in tibiae of rabbits. Considering the human bone activity, it is better to apply the orthodontic force $3{\sim}4$ weeks later than to apply it immediately after the insertion of orthodontic miniscrew implants. Considering that general orthodontic force is about $250{\sim}500$ grams, the tapered type can be worked as a stable skeletal anchor age in an orthodontic treatment even if the orthodontic force is applied on it immediately after the insertion of it.

• Food Science of Animal Resources
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• v.35 no.6
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• pp.859-866
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• 2015

To determine chemical components and meat quality traits related to palatability of 10 primal cuts, 25 Hanwoo carcasses were selected from 5 carcasses × 5 quality grades and used to obtain proximate data and meat quality characteristics. Significant differences (p<0.05) in chemical component and meat quality were found among the 10 primal cuts. The highest fat content was found in the kalbi, followed by dungsim, yangjee, chaekeut, ansim, abdari, suldo, moksim, udun, and satae. Protein and moisture contents in the 10 primal cuts were in reverse order of fat content. Moksim had the highest drip loss % and cooking loss % than all other primal cuts while kalbi showed the lowest (p<0.05) percentage of drip and cooking loss. Ansim had the longest sarcomere length but the lowest shear force values than all other cuts (p<0.05). The highest (p<0.05) score for overall acceptability was observed in ansim. Moksim, udun, abdari, and satae were rated the lowest (p<0.05) in overall acceptability among the 10 primal cuts from Hanwoo carcasses. In conclusion, ansim, dungsim, chaekeut, and kalbi had the highest overall acceptability due to their higher fat contents and lower shear force values.

• The Korean Journal of Food And Nutrition
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• v.11 no.4
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• pp.409-415
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• 1998

This study was carried out to investigate the effects of freezing temperature on quality of vacuum packaging freezed beef. In case of thaw drip loss, the freezing of -3$^{\circ}C$ and -20$^{\circ}C$ were 5.23% and 5.17% to 60 days respectively, were increased significantly during freezing. The cooking loss of water bath and pan were increased significantly during freezing than the beginning of freezing, but were no different between -3$^{\circ}C$ and -20$^{\circ}C$. The salt soluble protein extractability was decreased during freezing, the -20$^{\circ}C$ freezing was higher than -3$^{\circ}C$freezing. The water soluble protein extractability was increased during freezing higher than during freezing. The myoglobin denatured percentage of the -3$^{\circ}C$ freezing was higher than -20$^{\circ}C$ freezing, the 15 days storage of -3$^{\circ}C$ freezing was highest to 96%. The shear force value was not change during freezing, the myofibrillar fragmentation index during freezing was higher than the beginning of freezing, but was not change during freezing. The pH was decreased to freezing 45 days, after that increased.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.86.1-86.1
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• 2012

The MHD virial theorem applied for observed photospheric field may be the one of way to estimate magnetic energy of generally invisible coronal magnetic structure. However, the photospheric field is not in a force-free state, so the application of virial theory needs some care. Here we use a series of MHD simulations of emerging field to investigate how we can apply the virial theorem to the emerging field. In early emerging phase, virial energy has a minus value although positive area at the photosphere is continuously generated toward a late emerging phase. We discuss why this tendency occurs. Then we derive the critical height where the actual emerging magnetic energy is almost comparable to the virial energy. If the difference between virial energy and magnetic energy becomes 10 percentage of the magnetic energy, we define this is the critical height, and assume the emerging field is close to force-free. We also discuss how the critical height changes with the initial twist of an emerging flux tube.