• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.2
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• pp.265-277
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• 1998

In this paper, to investigate the possibility of fading reduction effect and high transmission rate in indoor multipath propagation environment, we measured and analyzed broadband signal conducting by frequency sweeping method in LOS(Line-of-Sight) environment. In measuring, we used vertically polarized, horizonatally polarized and circularly polarized and circularly polarized antenna to compare the fading reduction effect and the characteristic of bandwidth amplitude fluctuation between each broadband signals. As a result, it can be seen that the circularly polarized antenna can reduce the amplitude deviation of the broadband signal because it can remove the odd-times reflected wave in LOS environment. And also, It was found that the best effective diversity reception method is to use polarization branches, which install a circularly polarized antenna at the transmitting end and compose the vertical and horizontal antenna at the receiving end.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.61-65
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• 2011

In this paper, the nozzle design with asymmetric configuration using the optimal method is used in order to improve the under- and over-expansion problem of the flow at the supersonic turbine nozzle. For the design of nozzle contour, 8 design variables are selected and the total-to-static efficiency from the nozzle inlet to the wake outlet is considered as the objective function to be maximized. The Fluent6.3 and the iSIGHT-FD program are used for calculation of nozzle flow and design optimization respectively. RBF(Radial Basis Function) method is chosen for approximate optimization algorithm. It is shown that the static efficiency of improved nozzle design increases 1.35% and loss coefficient decreases 19.85% as compared to baseline design.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.61.4-62
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• 2020

We present H I gas kinematics and star formation activities of NGC 6822, a dwarf galaxy located in the Local Volume at a distance of ~490 kpc. We perform profile decomposition of the line-of-sight velocity profiles of the high-resolution (~42.4" × 12") spatial; ~1.6 km/s spectral) H I data cube taken with the Australia Telescope Compact Array (ATCA). For this, we use a new tool, the so-called BAYGAUD (BAYesian GAUssian Decompositor) which is based on Bayesian Markov Chain Monte Carlo (MCMC) techniques, allowing us to decompose a line-of-sight velocity profile into an optimal number of Gaussian components in a quantitative manner. We classify the decomposed H I gas components of NGC 6822 into kinematically cold, warm or hot ones with respect to their velocity dispersion: 1) cold: < 4 km/s, 2) warm: 4 ~ 8 km/s, 3) hot: > 8 km/s. We then derive the Toomre-Q parameters of NGC 6822 using the kinematically decomposed H I gas maps. We also correlate their gas surface densities with the surface star formation rates derived using both GALEX far-ultraviolet and WISE 22 micron data to examine the impact of gas turbulence caused by stellar feedback on the Kennicutt-Schmidt (K-S) law. The kinematically cold component is likely to better follow the linear extension of the Kennicutt-Schmidt (K-S) law for molecular hydrogen (H2) at the low gas surface density regime where H I is not saturated.

• Journal of Environmental Science International
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• v.11 no.9
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• pp.843-849
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• 2002

According to tourism resources in Kyonggi province, tourist behavior was dramatically different in that tourists utilizing natural resources were mainly interested in static tourism activities and sight seeing activities while tourist using socio-cultural resources preferred with dynamic tourism activities and relaxation tourism. Therefore, the objectives of reconstruction should be adjusted depending on types of tourism resources (i.e. natural and socio-cultural resources) or natural intensity as well as the development goal of recreational tourism. In contrast, historic and cultural resources surrounded with natural resources showed higher revisit rate, and was conceived as better touring site than individual resource because of historical people, traditional custom, natural sight seeing, etc. Therefore, it is believed that proper utilization of natural resources will increase revisit rate and create new conception as a famous touring site.

• The Mathematical Education
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• v.40 no.1
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• pp.15-25
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• 2001

The purpose of this thesis is to search the situation of an outbreak of the fallacy and methods of its treatment. We regard intuition as origins of genuine knowledge, but it sometimes raises the fallacy by intrinsic characters of itself. It makes an examination of the fallacy of the sense of sight like an optical illusion to instance that of sense. The sense of sight is an important factor in an intuitive cognition. However, its activity without thinking raises the fallacy of intuition in the process to observe and judge the things. I point out the fallacy of intuition which originates from terms and concepts in mathematical problems. The concept of mean velocity is representative. In this case, students make a mistake which means velocity can be solved by dividing the sum of v$_1$ and v$_2$ into two. The methods which overcome the fallacy of intuition are balance of intuition and logic, overcome of functional fixedness, the development of intuitive models and the development of metacognitive ability.

• Publications of The Korean Astronomical Society
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• v.19 no.1
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• pp.17-20
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• 2004

In this paper, the intensity ratio of [O I] $\lambda6300$ and $H_\alpha$ lines, which plays an important role in the study of warm (or diffuse) ionized interstellar medium, is calculated assuming collisional ionization equilibrium (or coronal equilibrium). The calculated ratio is compared with the previous works, and with the observations, obtained by Reynolds (1989) and Reynolds et al. (1998) with the Wisconsin Ha Mapper facility, toward the directions that sample the faint interstellar emission-line background. The comparison confirms that most of the Ha originates from nearly fully ionized regions along the lines of sight rather than from partially ionized H I clouds or layers of H II on the surfaces of H I clouds.

• The Journal of Korean Medicine
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• v.19 no.2
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• pp.137-152
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• 1998

Acute complications of diabetes mellitus were diminished after Banting and Best discovered insulin. But chronic complications of diabetes mellitus have been increased. The main complications of diabetes mellitus are diabetic retinopathy, diabetic nephropathy, diabetic neuropathy, diabetic foot lesion and macrovascular complication. These complications can result in renal failure, loss of sight, cerebral infarction and myocardial infarction. So it is very difficult to treat the complications of diabetes mellitus. In oriental medicine, the transformations(傳變症) of Sogal(消渴) are edema, carbuncle, loss of sight and so on. The comparative study between the trcmsformations(傳變症) of SogaI(消渴) and the complications of diabetes mellitus has come to the following conclusions. 1. In oriental medicine, diabetic retinopathy was expessed as loss of sight and the treament of diabetic retinopathy should be started at an early stage, to prevent vitreous hemorrhage and traction retinal detachment. 2. In oriental medicine. diabetic nephropathy was expressed as edema and the treatment should be started at an early stage of renal injury when the protein comes from urine.3. Symmetrical distal polyneuropathy is the main part of diabetic neuropathy and it was expressed as weakness of the lower limbs and pain of joints in the symptoms of Haso(下消). In Oriental medicine, acupuncture and herb medicine which effect is SopungHwalHyul can treat polyneuropathy. 4. Chief macrovascular complications are coronary artery disease and cerebrovascular disease, The cause of macrovascular complication is atherosclerosis. So the method of treating atherosclerosis should be studied in oriental medicine. 5. Diabetic foot were expressed as carbuncle and its main causes are decreasing perfusion of fool, diabetic neuropathy and infection. So these causes should be studied in oriental medicine. 6. The complications of diabetes mellitus afe very similar to the transfonnatiuns of Sogal(消渴).The control of blood glucose is indispensable to prevent and delay the complication of diabetes mellitus.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.66-66
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• 2004

중량은 항공기의 성능을 좌우하는 주요 변수로써, 최소의 중량 달성이 100여 년 전 라이트 형제가 최초의 비행을 성공한 후, 항공기 개발자들의 주요 관심사였다. 일반 구조물의 최적화를 통한 설계는 구조물의 강도를 유지하면서 중량절감, 비용절감을 위해 널리 사용되고 있다. 하지만, 현재 항공기 구조물에 대해서는 아직 최적화론 통한 설계가 널리 적용되지 않고 있다. 그래서, 항공기에서는 중량절감을 위해 가벼우면서 강도를 큰 알루미늄이 주재료로 사용되고 있다.(중략)

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.41.1-41.1
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• 2021

Neutral (HI) gas clouds associated with galaxies are responsible for fuelling the star-formation in the universe. In literature, the extremely strong damped Lyman-alpha absorbers (or ESDLAs) have been known to be sensitive to the effects of HI-H2 transition and star-formation in galaxies. Yet, ESDLAs are rare to probe due to the smaller cross section they subtend on the sky (similar to galaxies). In my talk, I will focus primarily on my study of the nature of ESDLAs that are observed as absorption signature along the line-of-sight (LOS) of a quasar (QSO). I will further look at the HI-H2 transition and interesting results relevant to diffuse molecular gas and the multi-phase medium (gas in different ionization states) that are associated with ESDLAs. Furthermore, I will also discuss how the ESDLA environments differ from the high star-forming and molecular environments detected in blind optical and radio surveys consecutively.

• Proceedings of the Korea Contents Association Conference
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• 2003.05a
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• pp.185-188
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• 2003

Entrance on the stage of electronic commerce based on internet is acting role that take away regional limitation in commercial transaction. This means that must establish common idea until now in commercial transaction newly, That is, feeler escapes in pattern that is been prior and it means that sight is been prior. We say too much may not be even if success and failure availability of electronic commerce shopping mall catches this sight. And, We Must be able to meet and attach goods purchase by construction of shopping mall through development of correct contents about in various desire of costomer. Therefore, in this paper, we recognize and studied about the efficiency of practical use for useful contents to satisfy customer'a desire in shopping mall construction.