• Journal of the Korea Concrete Institute
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• v.21 no.1
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• pp.93-103
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• 2009

The concept of the effective moment of inertia has been generally used for the deflection estimation of reinforced concrete flexural members. The KCI design code adopted Branson's equation for simple calculation of deflection, in which a representative value of the effective moment of inertia is used for the whole length of a member. However, the code equation for the effective moment of inertia was formulated based on the results of beam tests subjected to uniformly distributed loads, which may not effectively account for those of members under different loading conditions. Therefore, this study aimed to verify the influences of moment shapes resulting from different loading patterns by experiments. Six beams were fabricated and tested in this study, where primary variables were concrete compressive strengths and loading distances from supports, and test results were compared to the code equation and other existing approaches. A method utilizing variational analysis for the deflection estimation has been also proposed, which accounts for the influences of moment shapes to the effective moment of inertia. The test results indicated that the effective moment of inertia was somewhat influenced by the moment shape, and that this influence of moment shape to the effective moment of inertia was not captured by the code equation. Compared to the code equation, the proposed method had smaller variation in the ratios of the test results to the estimated values of beam deflections. Therefore, the proposed method is considered to be a good approach to take into account the influence of moment shape for the estimation of beam deflection, however, the differences between test results and estimated deflections show that more researches are still required to improve its accuracy by modifying the shape function of deflection.

• Microbiology and Biotechnology Letters
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• v.36 no.3
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• pp.201-208
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• 2008

To produce bioactivity-strengthen medicinal herbs, the 36 medicinal herbs which have antioxidation or blood circulation activity, were solid fermented using Phellinus baumii mycelium. Most of medicinal herbs, except Chrysanthemum indicum (flower), Zizyphus jujuba Miller (fructus), Aconitum koreanum R. Raymond (root), Magnolia denu-data (flower), and Polygonatum sibiricum Redt (root bark), showed good fermentation at $25^{\circ}C$ for 20 days under 90% of relative humidity. The poor fermentations of the herbs could be explained by lack of nutrient, structural rigidity, and the content of antifungal substance. After fermentation, the average water content of herbs were increased to $67.21{\pm}11.43%$ from $30.84{\pm}15.67%$, but the average pH and average methanol extraction ratio were slightly decreased to $11.16{\pm}7.06%$ and $4.83{\pm}0.73$ from $13.91{\pm}12.22%$ and $5.06{\pm}0.87$, respectively. The analysis of thrombin inhibition and DPPH scavenging activity of the methanol extracts of herbs showed that thrombin inhibition activities of the fermented Drynaria fortunei Kunze, Melia azedarach var. japonica, Prunus persica and Orostachys japonicus, and DPPH scavenging activities of the fermented Polygala tenuifolia, Scrophularia buergeriana, Angelica dahurica, Drynariafortunei Kunze, Cyperus rotundus, and Boschniakia rossica were increased as compared with those activities of non-fermented its cognate herbs. Our results suggest that the production of bioactivity-strengthen medicinal herbs is possible by solid fermentation of Phellinus baumii mycelium, as fermented Drynaria fortunei Kunze showed increased antioxidant and thrombin inhibitory activities than those of non-fermented herbs.

• Journal of Veterinary Clinics
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• v.28 no.5
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• pp.479-485
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• 2011

The cardiopulmonary responses during total intravenous anesthesia (TIVA) between remifentanil/propofol infusion and remifentanil/ketamine infusion in dogs were compared. Fourteen healthy adult beagle dogs were premedicated with acepromazine (0.1 mg/kg, SC) and medetomidine (20 ${\mu}g$/kg, IV), and anesthetized for 3 hr with remifentanil (0.5 ${\mu}g$/kg/min)/propofol (loading dose: 1 mg/kg, CRI: 0.3 mg/kg/min) CRI (group 'P') or remifentanil/ ketamine (loading dose : 5 mg/kg, CRI: 0.1 mg/kg/min) CRI (group 'K'), respectively. Hemodynamics, blood gas analysis and behavioral changes during recovery were measured. The level of anesthesia was determined by toe-web clamping test. The level of surgical anesthesia was maintained throughout the experiment in both groups. Systolic arterial pressure, mean arterial pressure, $PaO_2$ and $SpO_2$ in group 'K' were significantly higher than in group 'P', and were maintained near the normal ranges. In addition, $PaO_2$ in group 'K' was significantly lower than in group 'P'. However, diastolic arterial pressure, heart rate and respiratory rate were not significantly differed. Mean extubation time from the end of infusion was significantly reduced in group 'K', but mean sitting time was significantly reduced in group 'P'. Mean head-up time and mean walking time were not significantly differed. In group 'K', brief muscle rigidity, head waving and licking during recovery were observed. In conclusion, infusion rate of ketamine (0.1 mg/ kg/min) with remifentanil (0.5 ${\mu}g$/kg/min) is an appropriate for obtaining the surgical plane of anesthesia. These results showed that group 'K' had better cardiopulmonary function than group 'P'. That is, remifentanil/ketamine CRI is better TIVA protocol than remifentanil/propofol CRI for 3 hr surgery.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1061-1071
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• 2018

A subsea tunnel, being a super-sized underground structure must ensure safety at the time of earthquake, as well as at ordinary times. At the time of earthquake, in particular, of a subsea tunnel, a variety of response behaviors are induced owing to relative rigidity to the surrounding ground, or difference of displacement, so that the behavior characteristics can be hardly anticipated. The investigation aims to understand the behavior characteristics switched by earthquake of an imaginary subsea tunnel which passes through a fault zone having different physical properties from those of the surrounding ground. In order to achieve the aim, dynamic response behaviors of a subsea tunnel which passes through a fault zone were observed by means of indoor experiments. For the sake of improved earthquake resistance, a shape of subsea tunnel to which flexible segments have been applied was considered. Afterward, it is believed that a D/B can be established through 3-dimensional earthquake resistance interpretation of various grounds, on the basis of verified results from the experiments and interpretations under various conditions. The present investigation performed 1 g shaking table test in order to verify the result of 3-dimensional earthquake resistance interpretation. A model considering the similitude (1:100) of a scale-down model test was manufactured, and tests for three (3) Cases were carried out. Incident seismic wave was introduced by artificial seismic wave having both long-period and short-period earthquake properties in the horizontal direction which is rectangular to the processing direction of the tunnel, so that a fault zone was modeled. For numerical analysis, elastic modulus of the fault zone was assumed 1/5 value of the modulus of individual grounds surround the tunnel, in order to simulate a fault zone. Resultantly, reduced acceleration was confirmed with increase of physical properties of the fault zone, and the result from the shaking table test showed the same tendency as the result from 3-dimensional interpretation.