• Asian-Australasian Journal of Animal Sciences
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• v.7 no.2
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• pp.255-260
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• 1994

Calving records of 107 heifers from two breed groups were used to identify the major factors contributing to calving difficulty (dystocia) and compare the influence of pelvic diameters, weight and height of heifers measured after breeding and before calving on dystocia. The horizontal and vertical pelvic diameters, hip height and weight of heifers were measured two months after breeding and again two months before calving. Snell transformed calving difficulty scores (0 = normal to 100 = surgical intervention) were used in analyzing the data by analysis of covariance. Body condition score of the heifer, sire birth weight of the calf, birth weight of the calf, and ratio of calf birth weight to pelvic area all had significant effects on dystocia. Calf birth weight, ratio of calf birth weight to pelvic area, and heifer's condition score were especially important. However, sex of calf did not have a significant influence on dystocia. Generally, the variables measured before calving accounted for a higher proportion of variation in dystocia than those measured after breeding. Thus, based on the relative importance of the major factors affecting dystocia, it is suggested that selection of bulls with low birth weight for breeding on normal size heifers with optimum body condition score, and well developed pelvic opening, would be effective in reducing the incidence and severity of dystocia in beef heifers.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.3 s.118
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• pp.315-322
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• 2007

In this paper, active integrated antenna with left hand circular polarization(LHCP) for a transmitter of UHF RFID reader has been described. A novel rectangular ring patch as a radiator of the active antenna is proposed for easier impedance matching, smaller patch size, and LHCP characteristics. An amplification circuit is placed in the opening area of the radiator and is combined with it to work as oscillating circuit around 915 MHz. From the test results, impedance bandwidth of 29 MHz, 3 dB axial ratio bandwidth of 20 MHz, 3 dB beamwidth of 85 degree, and effective radiation power of 8.8 dBm have been obtained.

• Steel and Composite Structures
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• v.51 no.1
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• pp.63-72
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• 2024

This study delves into the interaction dynamics between lateral notches and inclusions, providing valuable insights for more effective engineering of structural components. By employing the finite element method, the research analyzes how inclusions affect the dimensions and contours of the plastic zone under confined plasticity conditions. Several parameters were investigated, including loading influence, the distance between the inclusion and notch tip, inclusion stiffness, and the distribution of Von Mises stress, as well as normal stresses σxx and σyy, and Comparison between different stresses. Examining stress distributions under varying loading conditions reveals a significant intensification, particularly near the crack tip. Moreover, the presence of an inclusion near the notch base reduces both the size and shape of the plastic zone. The distribution of the stresses for different loads knows an increase in intensity, especially near the crack head, which is the most requested by the tensile forces on its upper part, which can cause either the crack's initiation or opening, inducing significant stresses.

• International Area Studies Review
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• v.20 no.2
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• pp.3-23
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• 2016

In this study, we used actual proof analysis, based on SVAR model according to economy theory, to observe the impact of actual and financial market of Korea, Japan, and China that have adopted quantitative easing export based strategy of growth, an unconventional monetary policy of the U.S. As a result of estimation, it appears that real effective exchange rate rise shock of Korea, Japan, and China against U.S. dollar has a negative influence on current account and index of industrial product, which are real economy. It can be implied that the result is driven from the fact that strong home currency of Korea, Japan, and China decreases price competitiveness of exports, causing negative influence on real economy. The real effective exchange rate shock against U.S. dollar appeared to decrease national bond rate of Korea and Japan, while increasing that of China. In instances of Korea and Japan, it is implied that national bond rate decreases as foreigner investment funds flow in, considering foreign-exchange profit through advanced financial market with high opening extent. On the other hand, because there are strong regulation on opening extent of Chinese financial markets, the influence seems to be greater for domestic policy, rather than a foreign influence. Lastly, Korea showed a more dramatic variable reaction to exchange rate shock compared to Japan or China. It is implied from the result that Korea is relatively more susceptible and fragile in regards of international status of economic size and currency.

• Journal of Dental Anesthesia and Pain Medicine
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• v.18 no.3
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• pp.161-167
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• 2018

Background: This study aimed to evaluate the anti-inflammatory efficacy of preemptive intravenous ibuprofen on inflammatory complications such as edema and trismus in patients undergoing impacted mandibular third molar surgery. Methods: Sixty patients were included and divided into three groups (800 mg IV ibuprofen + 50 mg dexketoprofen, 800 mg IV ibuprofen, and control). In all patients, preoperative hemodynamic values were recorded before the infusions. The operation was started at 15-min post-infusion. Evaluation of edema size on the face and mouth opening (trismus) was conducted in the preoperative period, and at postoperative 48 h and 1 week. Results: No difference was determined among the groups in trismus and edema size in postoperative measurements (P > 0.05). There was a difference between group 2 and group 3 only in measurement value of tragus-corner of the mouth on the postoperative day 2 (P < 0.05). A difference was found between the measurement values of trismus preoperatively and at preoperative day 2, and between postoperative day 2 and 1 week in group 3 based on time (P < 0.05). In group 3, edema on the face on postoperative day 2 increased significantly compared to that in the preoperative period (P < 0.001); in addition, edema increased significantly in groups 1 and 2 in the postoperative period but was less than that in group 3 (P < 0.001). Conclusions: In this study, intravenous ibuprofen was determined to be more effective alone or in combination in alleviating trismus and to better limit the postoperative edema.

• Polymer(Korea)
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• v.29 no.5
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• pp.440-444
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• 2005

An increase in the surface area of drugs by reducing particle sizes from microns to nanometers has been known as an efficient method to improve the bioavailability of water-insoluble drugs. To prevent drug nanoparticles from aggregation during the processes of drug formulation, a limited number of pharmaceutical inactive ingredients such as hydroxypropyl cellulose has been employed as stabilizers or dispersants. In this study, copolymers of hydrophilic and hydrophobic amino acids were synthesized by the ring opening polymerization of their N-carboxyanhydride monomers and evaluated as novel candidates to stabilize the nanoparticles of a water insoluble drug, naproxen. Naproxen nanoparticles stabilized by synthesized amino acid copolymers were successfully prepared in the size of $200\~500nm$ in 60 min by a wet comminution process. Particle size analysis showed that the effective stabilization performance of copolymers required the hydrophobic moiety content to be higher than $10 mol\%$. However, the molecular weight and morphology of copolymers was not the critical parameters in determining the particle size reduction. Their particle size was found to be stable up to 14 days without significant aggregation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4A
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• pp.337-342
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• 2010

Generally most sluice gates are closed and opened by a mechanical winch, a winch using an oil-pressure, or a winch mixing both. Because of their size and structure, they should be safely operated with more than two pulling devices helping each other. At the moment of their opening and closing, there usually occur some additional loads to the structure which cannot be exactly measurable at the stage of designing. Such additional loads can cause the sluice gate to be unbalanced and make it hard to open and close the gate, and by also overloading a winch, they can inflict a significant damage to the safety of the sluice gate. This paper explains a FDC(Force-Displacement Control) system which simultaneously considered the oil-pressure and displacement in order to evenly distribute the force and make a winch balanced at the opening and closing motion. This FDC system was implemented by means of the PID(Proportional Integral Derivative) function of XG 5000 program. It was experimented on a model of the sluice gate winch with the hydraulic oil pressure cylinder. The experiments showed that the developed FDC system made the winch of hydraulic oil pressure cylinder open and close cooperatively in spite of various external loads. Therefore the FDC system is proven effective when it is applied to a winch of sluice gate.

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.279-284
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• 2009

The formation of mesoporous pores in the microporous mordenite crystals was performed by controlled silica extraction on alkaline treatment. Inner tunable mesopore size could be controlled by changing the concentration of alkaline solution. The pore structure of mordenite zeolite was studied by instrumental analysis after alkaline-treatment. To obtain the cage type mesopores, Ti-coating on the ourside mordenite crystals before alkaline treatment was investigated to be the most effective. Polymeric chiral salen Co (III) complexes were successfully encapsulated in mesoporous mordenite zeolite by "ship-in-a-bottle" method. The heterogeneous catalyst could be applied in asymmetric ring opening of epichlorohydrine by water. It showed very excellent enantioselectivity with a high yield in the catalysis.

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.2
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• pp.213-222
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• 2001

Cylindrical type ceramic filers, that is 60 O.D$\times$10t$\times$600L and 60 O.D$\times$10t$\times$1,000L were manufactured by vacuum forming processes using ceramic ray materials. For cylindrical type ceramic filters, porosity and bulk density were measured for, 80 to 90% and 0.3 to 0.4 g/㎤, respectively at uniform pore size of 41 to 45${\mu}{\textrm}{m}$. Bench scale candle filters (60$\psi$ $\times$10t$\times$600L) were tested using different dusts collected from many industries including chemical processing, glass processing and metal manufacturing pants. Collection efficiencies found out to range from 99.87% to 99.90%, while resistance coefficients from 1.1$\times$10(sup)11/$m^2$ to 1.7$\times$10(sup)11/$m^2$ . Full scale low density ceramic filters (60$\psi$ $\times$10t$\times$1,000L) were also tested at 1 atm, $600^{\circ}C$ to reveal the filtration efficiency, conditioning, and resistance coefficients using two different types of dust as chemical processing and metal refined processing. Darcys law resistance coefficients were measured to range 1.44$\times$10(sup)11/$m^2$ to 2.74$\times$10(sup)11/$m^2$, and collection efficiencies on the range 99.84 to 99.96%, Finally, results of long term performance test showed that filters were conditioned after 170hrs. Experimental conditions for effective filtration were examined under the condition 10 cm/sec face velocity, 3kg/$\textrm{cm}^2$ pulsing pressure, 5 min filtration cycle, and 300msec pulse opening time.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.41
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• pp.29.1-29.10
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• 2019

Background: Reduction in postoperative complications is of vital considerations in impacted third molar teeth surgery. The aim of this study was to compare postoperative complications of impacted third molar surgeries for bone removal using laser, piezoelectric equipment, and conventional rotary instruments. Methods: To address the research purpose, the investigator designed the prospective double-blind clinical trial study. The sample size was determined 20 (40 teeth) by sampling formula in any kind of operation. The data of patients were obtained in the different periods in terms of pain, trismus, swelling, ecchymosis, and patient's satisfaction and then analyzed using SPSS 20 software via paired t test and Wilcoxon and McNemar's tests. Results: The pain immediately after surgery and 2 days and 7 days after surgery was higher in the laser group. The swelling immediately after surgery was more in the laser group but not significant. The amount of mouth opening immediately after surgery and 2 days and 7 days after surgery was significantly lower in the laser group than in the piezosurgery group. The total duration of surgery and duration of osteotomy were significantly longer in the laser group. The patient's satisfaction from surgery with piezosurgery was more than that with laser, but this difference was not significant. Conclusion: Due to the rising demand for impacted wisdom tooth surgery, the present study suggests that hard tissue laser surgery and piezosurgery can clear the future of impacted molar surgery, and these approaches are more efficient in reducing postoperative complications compared to the conventional surgeries.