• Journal of Advanced Navigation Technology
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• v.27 no.5
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• pp.587-593
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• 2023

In this paper, we propose a systematic design approach based on cavity-mode resonance analysis to improve the radiated susceptibility of cables in air vehicles. As electronic devices equipped in air vehicles substantially increase, enhancing the radiated susceptibility of internal cables becomes more challenging and significant. The proposed design approach provides an efficient method to avoid and suppress cavity-mode resonances using analytical methods to estimate the resonance frequencies and the current ratio induced by the cavity-mode resonances. It is demonstrated in simulated results that the proposed method offers a design solution for improving the radiated susceptibility and reduces the computation time by up to 99.6% compared to the previous design method.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.499-509
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• 2005

We have many foundations which were constructed on the karstic areas where solution cavities and fractured zone may form under, or close to foundations. The fact that the ground under the pier foundations was reinforced with the three axial high pressure jet grouting is confirmed through out about two hundred design reports. It is necessary that evaluation of a simple application of high pressure jet grouting method on the karstic areas containing solution cavities. In this study, the improved situation and reinforcing methods of the ground under the pier foundations are proposed based on the evaluation of design reports for the express highway and No.38 national roads.

• Journal of Veterinary Clinics
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• v.13 no.2
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• pp.144-148
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• 1996

The effectiveness of sodium carboxymethylcellulose (SCMC) and deztran in the prevention of adhesion formation on the uterus and embryo collection in rabbits was elucidated. Following induction of adhesion on uterus and uterine horns by abrasion and retrograde flushing of embryos in gonadotropins primed rabbits, the solutions of saline (for control), 1% SCMC, 10% dextran and a synthetic solution of 1% SCNC and 10% dextran in saline were infused in the abdominal cavity at the dose of 5 ml/kg of body weight. The average percentage of adhesion was 11.1, 28.6, 41.7 and 73.3% in the rabbits infused with the synthetic, 1% SCMC, 10% dextran and saline solutions, respectively. The synthetic solution was more effective than other solutions in the rabbits. The average number and recovery rate of embryos were significantly (P<0.01) higher in the synthetic solution group than 1% SCMC, 10% dextran or saline solution groups. Among the collected embryos in the groups, the distribution of the normal embryos was higher in the synthetic solution group (99%) and the 10% dextran solution group (95.7%) than the 1% SCMC solution group (78.4%) and saline (66.2%). Theretore, a synthetic solution which is combined with 1% SCMC and 10% deztran in saline can be effectively used for the prevention of adhesion formation after uterine surgery and embryo collection.

• Journal of Veterinary Clinics
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• v.21 no.4
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• pp.349-354
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• 2004

The effectiveness of a synthetic solution of sodium carboxymethy1cellulose (SCMC) and dextran in the prevention of adhesion formation following intestinal anastomosis of intestine in dogs was elucidated and compared with Interceed. Following induction of adhesion on jejunum of dogs by resection and intestinal anastomosis, the dogs were infused with a synthetic solution of 1% SCMC and 10% dextran in saline in the abdominal cavity at the dose of 5ml/kg of body weight or treated with Interceed membrane. Fourteen days after operation, all the dogs showed adhesion of anastomotic sites to surrounding tissues. The average score of adhesion was 0.50, 0.60 and 0.80 in the dogs infused with the synthetic solution, Interceed membrane and saline solution, respectively. The synthetic solution showed better result of adhesion prevention than Interceed or saline solution. No significant change of body weight, vital signs, hematological values and side effects after operation was found in each group. Therefore, a synthetic solution which is combined with 1% SCMC and 10% dextran in saline can be effectively used for the prevention of adhesion formation comparable to Interceed membrane following intestinal anastomosis in the dogs.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.251-255
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• 2009

This study was conducted to investigate effect of ionic strength and feeding times of a nutrient solution on reduction of stem cavity size and improvement of flower quality in chrysanthemum 'Baekma'. A nutrient solution was applied with different strengths at three stages, namely, transplanting, budding, and flowering. The solution EC was adjusted as 1.61.82.0, 1.81.81.8, 1.82.01.8, and $2.02.02.0dS{\cdot}m^{-1}$ in four treatments. Feeding frequency per a day were 4 times for 12 min., 8 times for 6 min., 12 times for 4 min., and 18 times for 2.7 min. each. Cut flower length as affected by different strengths of a nutrient solution was the greatest in the plot of EC $2.02.02.0dS{\cdot}m^{-1}$. However number of leaves, stem diameter, and leaf size were greater in EC $1.82.01.8dS{\cdot}m^{-1}$ than in other treatments. Also, petal number of petals was the greatest and stem cavity size was the smallest in the plot of EC $1.81.81.8dS{\cdot}m^{-1}$. Plant height, number of leaves, stem diameter, leaf size were greater in the plot with 12 times feed ing per a day. number of petal was most in the plot with 8 times feeding per day, while stem cavity size was the smallest in the plot with 12 times feed ing per a day. Therefore, the better plant growth, the smaller stem cavity size.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.6
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• pp.435-442
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• 2009

Three-dimensional heat transfer characteristics for natural convection flows are numerically investigated in the doubly-inclined cubical-cavity according to the variation of a newly defined orientation angle �� of the hot wall surface from horizontal plane at moderate Rayleigh numbers. Numerical simulations of laminar flows are conducted in the range of Rayleigh numbers($10^4{\leq}Ra{\leq}10^5$) and $0^{\circ}{\leq}{\alpha}90^{circ}$ with a solution code(PowerCFD) employing unstructured cell-centered method. Comparisons of the average Nusselt number at the cold face are made with benchmark solutions and experimental results found in the literature. It is found that the average Nusselt number at the cold wall has a maximum value around the specified orientation ${\alpha}$ at each Rayleigh number. Special attention is also paid to three-dimensional thermal characteristics in natural convection according to new orientation angles at Ra��= $1{\times}10^5$, in order to investigate a new additional heat transfer characteristic found in the range of above Ra = $6{\times}10^4$.

• Restorative Dentistry and Endodontics
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• v.10 no.1
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• pp.161-168
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• 1984

The purpose of this study was to examine the effect of heat generated by rotating bur on the dental hard tissue in vitro. Freshly extracted molar teeth with normal appearance from early 20's male were collected and experimental teeth were divided into 4 groups and the teeth in each group were prepared class I cavity with different clinical procedures as follows. The four methods were. I. 20,000rpm without coolant II. 20,000rpm with coolant III. 500,000rpm without coolant IV. 500,000rpm with coolant Five teeth were reserved intact as a control group. These teeth were longitudinally split into two parts by means of chisel after class I cavity preparation. In a control group 5 parts were boiled in water for 20 minutes and the other 5 specimens were not boiled. All specimens were immersed in 2% methylene blue dye solution and the image of dye penetration was examined and photographed under stereomicroscope. Followings were the results obtained through the study. 1. In control group, dye penetration of the unboiled specimens was increased than with the boiled group. 2. The specimens prepared cavity without coolant showed decreased dye penetration than with the coolant group. 3. 20,000rpm without coolant group showed the least dye penetration. 4. 500,000rpm with coolant group showed similar level of dye penetration to the unboiled specimens from the control group.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.296-303
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• 1998

The purpose of this study was to assess the effects of cavity designs on the marginal leakage of class 5 glass ionomer restorations. The five cavity designs were as follows ; notch shape(A group), notch shape with groove(B group), combined lesion(C group), combined lesion with groove and deep chamfer margin(D group) and combined lesion with groove and shoulder(E group), and each design had 10 cavities. After the cavities were restored with GIC, they were immersed in 0.5% basic fuchsin solution for 6 hours. The specimens were washed thoroughly and sectioned longitudinally in a buccolingual direction through the center of the restorations. The degree of marginal leakage was measured as the extent of dye penetration under the stereoscope. The results of this study were as follows 1. The enamel margins of all groups showed lesser leakage than dentin/cementum margins(p<0.05). 2. The combined lesion(C group) showed more leakage than notch shape(A group), but there was no siginificant difference(p>0.05). 3. In the notch shape, there was no influence on the marginal leakage by the groove preparation. 4. In the combined lesion, marginal leakage was decreased by the groove preparation and marginal modification.

• Advances in aircraft and spacecraft science
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• v.9 no.2
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• pp.95-102
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• 2022

The paper investigates the process of pulsation of a spherical cavity (bubble) in a liquid under the influence of a source of ultrasonic vibrations. The process of pulsation of a cavitation pocket in liquid is investigated. The Kirkwood-Bethe model was used to describe the motion. A numerical solution algorithm based on the Runge-Kutta-Felberg method of 4-5th order with adaptive selection of the integration step has been developed and implemented. It was revealed that if the initial bubble radius exceeds a certain value, then the bubble will perform several pulsations until the moment of collapse. The same applies to the case of exceeding the amplitude of ultrasonic vibrations of a certain value. The proposed algorithm makes it possible to fully describe the process of cavitation pulsations, to carry out comprehensive parametric studies and to evaluate the influence of various process parameters on the intensity of cavitation.

• Journal of KSNVE
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• v.7 no.4
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• pp.631-636
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• 1997

A method to estimate the radiatio power to the surrounding formation due to axial vibration of the pipe in a fluid-filled borehole has been developed, by using the propagation modes of stress wave in an infinitely-long and uniform drilling borehole surrounded by a radially-infinite homogeneous formation. Also, the equivalent damping coefficient for the axial vibration of the pipe has been derived. As an example, results for a real drilling borehole has been presented. The analysis of the elastic motion of the infinite formation which has cylidrical cavity is simplified with the geometric axisymmetry and the low-frequency assumption so that the analytic solution is obtained.