• 한국전산유체공학회:학술대회논문집
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• 2007.10a
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• pp.149-156
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• 2007

A three-dimensional inviscid flow solver has been developed based on unstructured meshes for the simulation of steady and unsteady flowfields around a generic fighter aircraft and for the investigation of the aerodynamic interference between the external stores and the tail surfaces. The flow solver is based on a vertex-centered finite-volume method and an implicit point Gauss-Seidel relaxation scheme. To validate the flow solver, calculations were made for a steady flow and the computed results were compared with experimental data. An unsteady time-accurate computation of the generic fighter aircraft with external stores at transonic flight conditions showed that the external stores cause undesirable vibration on the horizontal tail surface due to the mutual interference between their wake and the horizontal tail surface. It was shown that downward deflection of the trailing edge flap significantly reduces the undesirable interference effect.

• Proceedings of the Korean Statistical Society Conference
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• 2002.05a
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• pp.49-54
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• 2002

For arbitrary random variables {$X_{n},n{\geq}1$}, the order of growth of the series. $S_{n}\;=\;{\sum}_{j=1}^n\;X_{j}$ is studied in this paper. More specifically, when the series S_{n}$ diverges almost surely, the strong law of large numbers $S_{n}/g_{n}^{-1}$($A_{n}{\psi}(A_{n}))\;{\rightarrow}\;0$ a.s. is constructed by extending the results of Petrov (1973). On the other hand, if the series $S_{n}$ converges almost surely to a random variable S, then the tail series $T_{n}\;=\;S\;-\;S_{n-1}\;=\;{\sum}_{j=n}^{\infty}\;X_{j}$ is a well-defined sequence of random variables and converges to 0 almost surely. For the almost surely convergent series $S_{n}$, a tail series strong law of large numbers $T_{n}/g_{n}^{-1}(B_{n}{\psi}^{\ast}(B_{n}^{-1}))\;{\rightarrow}\;0$ a.s., which generalizes the result of Klesov (1984), is also established by investigating the duality between the limiting behavior of partial sums and that of tail series. In particular, an example is provided showing that the current work can prevail despite the fact that previous tail series strong law of large numbers does not work.

• Journal of the Korean Statistical Society
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• v.24 no.1
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• pp.91-109
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• 1995

The rate of convergence to a random variable S for an almost certainly convergent series $S_n = \sum^n_{j=1} X_j$ of independent random variables is studied in this paper. More specifically, when $S_n$ converges to S almost certainly, the tail series $T_n = \sum^{\infty}_{j=n} X_j$ is a well-defined sequence of random variable with $T_n \to 0$ a.c. Various sets of conditions are provided so that for a given numerical sequence $0 < b_n = o(1)$, the tail series strong law of large numbers $b^{-1}_n T_n \to 0$ a.c. holds. Moreover, these results are specialized to the case of the weighted i.i.d. random varialbes. Finally, example are provided and an open problem is posed.

• Physical Therapy Korea
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• v.5 no.2
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• pp.15-22
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• 1998

Laser photobiostimulation (LPBS) is one of the recent additions to therapeutic procedures used in chronic pain management. Though widely used, a clear understanding of its mechanism of action was not disclosed. In addition, the energy density that produces maximal benefit has not yet been established. The purposes of this study were to determine the effects of LPBS on pain relief in rat and to determine treatment dosage. Eight, 8-week old female, Sprague-Dawley rats were employed. All subjects were assigned to one of four groups: a sham laser group, a 0.4 $J/cm^2$ laser group, a 2.0 $J/cm^2$ laser group, and a 6.0 $J/cm^2$ laser group. Ga-As laser (904 nm wavelength) of three different energy densities (0.4, 2.0, 6.0 $J/cm^2$) was applied on a tail acupuncture point and tail-flick latencies were measured five times pre-and post-treatment as following schedules: 30 minutes, 1 hour. 24 hours. 48 hours, and 7 days later. An increase in pain threshold was demonstrated following LPBS, employing rat tail-flick test. LPBS of 2.0 $J/cm^2$ produced hypoalgesia of rapid onset and short duration (1 hour, 24 hours) while the response to 6.0 $J/cm^2$ was delayed and lasted longer (48 hours, 7 days). LPBS of 0.4 $J/cm^2$ did not produce any hypoalgesia.

• Journal of the Korean Society of Combustion
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• v.20 no.2
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• pp.36-39
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• 2015

The combustion characteristics of metal fiber burner fueled natural gas with tail gas produced from reforming process were analyzed on the point of flame stability and excess air conditions. Also, it was analyzed the effect of energy efficiency improvement due to decrease the fuel input in reforming system by using residue gases. As a results, it was confirmed that tail gas including hydrogen, CO and $CO_2$ could be directly injected without any change of air control system in natural gas burner and also energy efficiency was increased up to 30% maintained stable combustion.

• The Journal of Korean Physical Therapy
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• v.8 no.1
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• pp.15-20
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• 1996

The purpose of this study were to 1) determine the analgesic effect of 632.8 nm of helium-neon (He-Ne) laser stimulation on acupuncture point in rat and 2) determine the reversal of analgesic effect by naloxone injection. Eighteen Sprague-Dawley rats were devided into three groups : control (n=6) : laser (n=6), laser stimulation at $3.58\;J/cm^2$ ; and naloxone (n=6), 1 mg/kg of naloxone chloride inject into peritoneum before laser stimulation at $3.63J/cm^2$. Tail-flick latency were measured pretreat and posttreat with hot plate $(55^{\circ}C)$. Data were analyzed using one-way ANOVA and paired t-teat for tail-flick latency. No significant change was noted in the tail-flick latency in either control or naloxone groups. But significant increased in tail-flick latency in taller group. The results suggest that He-Ne laser induced analgesic effect, and endogenous opioids may be involved in He-Ne laser induced analgesia.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.5
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• pp.9-17
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• 2005

In the early stage of helicopter design, an optimal configuration is usually determined after a numerous parametric study about the aerodynamic performance due to geometric variation. In order to improve the aerodynamic performance of a shrouded tail rotor, optimization of the tip clearance gap between blade and shroud, the blade planform shape, and the arrangement of blade spacing is required. In the present study, the aerodynamic performance characteristics of a shrouded tail rotor due to geometric variation was investigated by using an inviscid compressible unstructured mesh flow solver for rotary wings.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1555-1559
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• 2003

The objective of the present study was to explore associations between five microsatellites linked to $Fec^B$ and $FecX^I$ genes and litter size in Small Tail Han sheep. The polymorphisms of five microsatellite loci, OarAE101, BM1329, BMS2508, TGLA54 and TGLA68 were detected in 244 ewes of Small Tail Han sheep. Analysis of association between three microsatellite loci (BMS2508, BM1329 and OarAE101) located in the 10 cM region covering the $Fec^B$ gene (Booroola gene) and litter size in Small Tail Han sheep indicated that BMS2508 had significant effect on litter size in the second parity (p<0.05), but no significant effect on litter size in the first parity (p>0.05), while the other two microsatellite loci had no significant effect on litter size in both the first and the second parity in Small Tail Han sheep (p>0.05). At microsatellite locus BMS2508, least squares means in the second parity of genotypes 101/111 and 99/109 were significantly higher than those of genotypes 99/99, 99/101, 99/111 and 99/115 (p<0.05); least squares mean in the second parity of genotype 101/111 was significantly higher than that of genotypes 109/111 and 111/111 (p<0.05). Results of this study also indicated that two microsatellite loci (TGLA54 and TGLA68) that confined the 28.7 cM region covering the $FecX^I$ gene (Inverdale gene) did not affect litter size in both the first and the second parity in Small Tail Han sheep significantly (p>0.05). The information found in the present study is very important for improving the reproductive performance in sheep breeds by marker assisted selection.

• Publications of The Korean Astronomical Society
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• v.15 no.spc2
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• pp.53-56
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• 2000

We investigate the critical issue on how the BBF (bursty bulk flow) is related to the substorm current wedge formation. Observationally, after analysing data sets from Geotail spacecraft at near tail and many ground magnetic observatories for 9 months period of 1996, we find three BBF events that clearly occurred at the center of the wedge with region I type FAC (field-aligned current), and two other BBF events that were seen outside the wedge sector. Theoretically, we suggest that the substorm current wedge generation by BBF is most likely when the h' VB contribution is dominant in the well-known MHD $J_{II}$ expression (Vasyliunaus, 1984) or when the divergence of the cross-tail current carried by the particle's gradient/curvature drift is predominantly sufficient at the moment of the BBF arrival at near tail.

• Nutrition Research and Practice
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• v.3 no.2
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• pp.114-121
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• 2009

The effect of diet supplemented with red beet (Beta vulgaris L.) leaf on antioxidant status of plasma and tissue was investigated in C57BL/6J mice. The mice were randomly divided into two groups after one-week acclimation, and fed a high fat (20%) and high cholesterol (1%) diet without (control group) or with 8% freeze-dried red beet leaf (RBL group) for 4 weeks. In RBL mice, lipid peroxidation determined as 2-thiobarbituric acid-reactive substances (TBARS value) was significantly reduced in the plasma and selected organs (liver, heart, and kidney). Levels of antioxidants (glutathione and $\beta$-carotene) and the activities of antioxidant enzyme (glutathione peroxidase) in plasma and liver were considerably increased, suggesting that antioxidant defenses were improved by RBL diet. Comet parameters such as tail DNA (%), tail extent moment, olive tail moment and tail length were significantly reduced by 25.1%, 49.4%, 35.4%, and 23.7%, respectively, in plasma lymphocyte DNA of RBL mice compared with control mice, and indicated the increased resistance of lymphocyte DNA to oxidative damage. In addition, the RBL diet controlled body weight together with a significant reduction of fat pad (retroperitoneal, epididymal, inguinal fat, and total fat). Therefore, the present study suggested that the supplementation of 8% red beet leaf in high fat high cholesterol diet could prevent lipid peroxidation and improve antioxidant defense system in the plasma and tissue of C57BL/6J mice.