• Title/Summary/Keyword: tail distribution

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Design of 2-Dimensional WIG Section by a Nonlinear Optimization Method (비선형 최적화 기법을 이용한 2차원 지면효과익의 형상설계)

  • Hee-Jung Kim;Ho-Hwan Chun
    • Journal of the Society of Naval Architects of Korea
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    • v.36 no.3
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    • pp.50-59
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    • 1999
  • This paper is concerned on the generation of an optimal section of wing in ground effect by a SQP method which is one of nonlinear optimization techniques. A potential panel method is used for the flow analysis and the ground effect is taken into account by an image method. The numerical method is first verified by an inverse problem where a shape of wing section is sought for the prescribed pressure distribution. The purpose of the present paper is to generate a wing section which can give a maximum lift subjected to the design constraints including the height stability which is important in the WIG design. The effect of the tail wing is also included.

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Tracing the Giant Metal-poor Halo Around the Sombrero

  • Kang, Jisu;Lee, Myung Gyoon;Jang, In Sung;Ko, Youkyung;Sohn, Jubee;Hwang, Narae
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.2
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    • pp.30.2-30.2
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    • 2016
  • M104 (NGC 4594, the Sombrero) is an intriguing disk galaxy classified as an elliptical galaxy nowadays. It hosts a luminous bulge and a massive disk, but it is still mysterious how M104 acquired such peculiar structures. Globular clusters are an useful tracer to investigate the formation history of early-type galaxies. In this study we present a wide field imaging study of the globular clusters in M104. Using wide ($1^{\circ}{\times}1^{\circ}$) and deep ugi images of M104 obtained with the CFHT/MegaCam observations, we detect a large number of globular clusters. The color distribution of these globular clusters shows that there are two subpopulations: a metal-poor system and a metal-rich system. The radial number density of the metal-poor globular clusters shows a long tail reaching R ~ 30' (~ 80 kpc), indicating clearly the existence of a giant metal-poor halo in M104. This result is consistent with the previous studies on the dual halos of massive early-type galaxies. We will discuss implications of these results in relation with the formation history of M104.

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Statistical analysis of SC-associated geosynchronous magnetic field perturbations

  • Kim, Gwan-Hyeok;Park, Jong-Seon;Lee, Dong-Hun;Jin, Ho
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.91.2-91.2
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    • 2012
  • Kokubun (1983) reported the local time variation of normalized amplitude of sudden commencement (SC) with a strong day-night asymmetry at geosynchronous orbit with 81 SC events. Further careful inspection of Kokubun's local time distribution reveals that the normalized SC amplitudes in the prenoon sector are larger than those in the postnoon sector. That is, there is a morning-afternoon asymmetry in the normalized SC amplitudes. Until now, however, there are no studies on this SC-associated morning-afternoon asymmetry at geosynchronous orbit. Motivated by this previous observation, we investigate a large data set (422 SC events in total) of geosynchronous SC observations and confirm that the geosynchronous SC amplitudes is larger in the morning sector than in the afternoon sector. This morning-asymmetry is probably caused by the enhancement of partial ring current, which is located in the premidnight sector, due to solar wind dynamic pressure increase. We also examine the latitudinal and seasonal variations of the normalized SC amplitude. We find that the SC-associated geosynchronous magnetic field perturbations are dependent on the magnetic latitude and season of the year. This may be due to the location of the magnetopause and cross-tail currents enhanced during SC interval with respect to geosynchronous spacecraft position.

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The Characteristics of Costume Color Design in Japanese Heian Period (일본 평안시대의 복식색채의장의 특성)

  • 이경희
    • Journal of the Korean Society of Costume
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    • v.31
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    • pp.17-31
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    • 1997
  • The Heian Period(794-1192) was the period when luxury and elegance flourished. Gorgeous colors were adopted for the costumes and an el-egant assortment of colors prevailed. Representatiove of such costumes is kasane-no-irome. The world Kasane-no-irome originally came from two colors on both sides of one of the japanese kimonos called Uchiki. In later times it turned to indicate the combination ef-fect of colors of several Uchiki's worn in layers one over the other. This paper describes in de-tail the kasane-no-irome in both meanings. In so doing I distinguish two different kinds of kasane-no-irome using a Chinese character for the formed and for the latter though both are pronounced Kasane in the Japanese language. Part one of this paper which concerns the color combinations of presents typical 148 samples through reproduced dyeing clothes by Matumoto. Part two describes the color com-bination of which was so called Junihitoe. It presents typical 41 samples from reproduced dyeing clothes by Matumoto. The purpose of this study was to investigate the characteristics of color distribution and the structure of color combination in Kasane-no-irome. Therefore we obtained the following results in Kasane-no-irome. 1. The color combination of Kasane-no-irome came from the natural color harmony there-fore the names of kasane-no-irome which adopt the names of flowers and leaves of the foure seasons. Accordingly the seasons for wearing them are fixed. 2. In the hue the most frequent appearance was green. And in the tone the most frequent apperance was moderate. 3. In the color combination the most fre-quent type were monochromatic combination and contrast combination.

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Distribution and accumulation of 177Lu-labeled thermally cross-linked superparamagnetic iron oxide nanoparticles in the tissues of ICR mice

  • Hue, Jin Joo;Lee, Hu-Jang;Nam, Sang Yoon;Kim, Jong-Soo;Lee, Beom Jun;Yun, Young Won
    • Korean Journal of Veterinary Research
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    • v.55 no.1
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    • pp.57-60
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    • 2015
  • To investigate kinetics of free $^{177}Lu$ and $^{177}Lu$-labeled thermally cross-linked superparamagnetic iron oxide nanoparticles (TCL-SPION), suspensions were intravenously injected into the tail vein of mice at a dose of $5{\mu}Ci$/mouse or 15 mg/kg body weight, respectively. Free $^{177}Lu$ radioactivity levels were highest in kidney followed by liver and lung 1 day post-injection. $^{177}Lu$-labeled TCL-SPION radioactivity in liver and spleen was significantly higher compared to that of other organs throughout the experimental period (p < 0.05). Radioactivity in blood, brain, and epididymis rapidly declined until 28 days. Based on these results, TCL-SPION could be a safe carrier of therapeutics.

Inundation Simulation of Underground Space using Critical Dry Depth Scheme (임계 마름 수심기법을 이용한 지하공간 침수 모의)

  • Rhee, Dong Sop;Kim, Hyung-Jun;Song, Chang Geun
    • Journal of the Korean Society of Safety
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    • v.30 no.6
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    • pp.63-69
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    • 2015
  • In this study, a 2D hydrodynamic model equipped with critical dry depth scheme was developed to reproduce the flow over staircase. The channel geometry of hydraulic experiment conducted by Ishigaki et al. was generated in the computational space, and the developed model was validated against flow properties such as discharge, velocity and momentum. In addition, the water surface profile and the velocity distribution evolved in flow over two layers staircases were analyzed. When the initial water depth at the upper floor was 0.3 m, the maximum velocity at lower floor was 4.2 m/s, and the maximum momentum was $1.2m^3/s^2$, and its conversion to force per unit width was 1.2 kN/m. This value was equivalent to the hydrostatic force with 50 cm water depth, and evacuation became difficult, as proposed by Ishigaki et al. For the flow over staircases connecting two layers, the maximum run-up height in flat part connecting two layers was approximately two times higher than the initial water depth in upper floor, and the rapid shock wave with sharp front and long tail was propagated.

The Influence of vibration during distribution of loose-formed eggs (Bombyx mori) to farmers (산란잠종배부시의 동요로 인한 영향)

  • 김원경
    • Journal of Sericultural and Entomological Science
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    • v.5
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    • pp.39-42
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    • 1965
  • The newly hatched silkworm can not come out with the head ahead, but on the contray, it comes out with the tail ahead when it comes out of the chorion, in case the loose-formed eggs are vibrated artificially, at the end of the incubation. So the newly hatched silkworm can not throw off the chorion alone which covers his head. This kind of eggs occurs about 30% when they are vibrated. In case they were raised, they could not grow well and some of them died. The result was quite bad. In conclusion, it would be better to distribute earlier the loose-formed eggs farmers and the loose-formed eggs must not be vibrated at the end of the incubation.

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Asymptotic Inference on the Odds Ratio via Saddlepoint Method (안부점근사를 이용한 승산비에 대한 점근적 추론)

  • Na, Jong-Hwa
    • Journal of the Korean Data and Information Science Society
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    • v.10 no.1
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    • pp.29-36
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    • 1999
  • We propose a new method of asymptotic inference on the odds ratio (or cross-product ratio) in $2{\times}2$ contingency table. Saddlepoint approximations to the conditional tail probability we used in this procedure. We assess the accuracy of the suggested method by comparing with the exact one. To obtain the exact values, we need very complicated calculations containing the cumulative probabilities of non-central hypergeometric distribution. The suggested method in this paper is very accurate even for small or moderate sample sizes as well as simple and easy to use. Example with a real data is also considered.

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Protein Structural Characterization by Hydrogen/Deuterium Exchange Mass Spectrometry with Top-down Electron Capture Dissociation

  • Yu, Hai Dong;Ahn, Seonghee;Kim, Byungjoo
    • Bulletin of the Korean Chemical Society
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    • v.34 no.5
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    • pp.1401-1406
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    • 2013
  • This study tested the feasibility of observing H/D exchange of intact protein by top-down electron capture dissociation (ECD) mass spectrometry for the investigation of protein structure. Ubiquitin is selected as a model system. Local structural information was obtained from the deuteration levels of c and $z^{\cdot}$ ions generated from ECD. Our results showed that ${\alpha}$-helix region has the lowest deuteration level and the C-terminal fraction containing a highly mobile tail has the highest deuteration level, which correlates well with previous X-Ray and HDX/NMR analyses. We studied site-specific H/D exchange kinetics by monitoring H/D exchange rate of several structural motives of ubiquitin. Two hydrogen bonded ${\beta}$-strands showed similar HDX rates. However, the outer ${\beta}$-strand always has higher deuteration level than the inner ${\beta}$-strand. The HDX rate of the turn structure (residues 8-11) is lower than that of ${\beta}$-strands (residues 1-7 and residues 12-17) it connects. Although isotopic distribution gets broader after H/D exchange which results in a limited number of backbone cleavage sites detected, our results demonstrate that this method can provide valuable detailed structural information of proteins. This approach should also be suitable for the structural investigation of other unknown proteins, protein conformational changes, as well as protein-protein interactions and dynamics.

Economic Valuation of Yeido Park: Application of Double-Bounded Dichotomous Choice Contingent Valuation Method (여의도공원의 경제적 가치평가: 二段階 二選 假想價値推定法을 적용하여)

    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.3
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    • pp.90-103
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    • 1998
  • The purposes of this study are to estimate the economic value and reasonable entrance fee of the Yeido Park, which is under construction in Seoul, by conduct the face-to-face interview. A total of 645 daults were selected by two stage cluster sampling. The senario was designed to meet the requirements for doubgle-bounded dichotomous choice CVM, and distributed with the photograph to epict and compare the current and suggested conditions. A donation vehicle and entrance fee were utilized to find the possibility of strategic behaviors and protest zero, and to make the data estimatable tfor interval censored survival analysis. Date was calibrated by the survival analysis to eleminate the 'fat-tail problem'. Weibull distribution was assumed as a baseline distrubution. The mean WTP of donation and entrance fee was ₩5,281 and ₩783, respectively. The economic value of this park was determined by aggregating the mean value, giving a total WTP for the population of ₩36,861,645,000. This economic value was composed with the use value and existence value. The calibrationi of the Weibull proportional hazard model showed that nearness to the park, age, intention to isit the park, and educational attainment were significant independent variable to influence an amount of donation.

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