• Title/Summary/Keyword: Mixed Space

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Effects of temperature and solution composition on evaporation of iodine as a part of estimating volatility of iodine under gamma irradiation

  • Yeon, Jei-Won;Jung, Sang-Hyuk
    • Nuclear Engineering and Technology
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    • v.49 no.8
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    • pp.1689-1695
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    • 2017
  • As a part of evaluating the volatility of iodide ions subjected to gamma irradiation, $I_2$ evaporation experiments were performed with $I_2$ and $I^-$ mixed solutions in the temperature range $26-80^{\circ}C$ in an open, well-ventilated space. The evaporation of $I_2$ was observed to follow primarily first order kinetics, depending on the $I_2$ concentration. The evaporation rate constant increased rapidly with increase in temperature. The presence of $I^-$ slightly reduced the evaporation rate of $I_2$ by forming relatively stable $I_3^-$. The effect of $Cl^-$ at <1.0 wt% on $I_2$ evaporation was insignificant. The evaporation rate constants of $I_2$ were $1.3{\times}10^{-3}min^{-1}\;cm^{-2}$, $2.4{\times}10^{-2}min^{-1}\;cm^{-2}$, and $8.6{\times}10^{-2}min^{-1}\;cm^{-2}$, at $26^{\circ}C$, $50^{\circ}C$, and $80^{\circ}C$, respectively.

All-fiber RGB Laser Light Source of Head-up Display System for Automobile Application

  • Lee, Jonggwan;Kim, Kyungwon;Son, Seong-Jin;Kim, Bok Hyeon;Yu, Nan Ei
    • Current Optics and Photonics
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    • v.4 no.3
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    • pp.221-228
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    • 2020
  • We developed an all-fiber RGB laser light source module for application in an automobile head-up display. It is based on laser diodes and an optical fiber combiner that substantially enhances the flexibility of configuration and stability against harsh working conditions for automobiles. We coupled 13 laser diodes with optical fibers and merged them into a single output with a beam combiner device. Red (R), green (G), and blue (B) laser sources were employed to produce primary colors that were mixed into a white light output. An optical output power of approximately 1.5 W was achieved, and the color balance of the output lights was assessed based on the CIE 1931 color space. The optical output power was shown to be stable for over 160 h within an optical fluctuation of less than 0.27%.

Mixing Collaborative and Hybrid Vision Devices for Robotic Applications (로봇 응용을 위한 협력 및 결합 비전 시스템)

  • Bazin, Jean-Charles;Kim, Sung-Heum;Choi, Dong-Geol;Lee, Joon-Young;Kweon, In-So
    • The Journal of Korea Robotics Society
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    • v.6 no.3
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    • pp.210-219
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    • 2011
  • This paper studies how to combine devices such as monocular/stereo cameras, motors for panning/tilting, fisheye lens and convex mirrors, in order to solve vision-based robotic problems. To overcome the well-known trade-offs between optical properties, we present two mixed versions of the new systems. The first system is the robot photographer with a conventional pan/tilt perspective camera and fisheye lens. The second system is the omnidirectional detector for a complete 360-degree field-of-view surveillance system. We build an original device that combines a stereo-catadioptric camera and a pan/tilt stereo-perspective camera, and also apply it in the real environment. Compared to the previous systems, we show benefits of two proposed systems in aspects of maintaining both high-speed and high resolution with collaborative moving cameras and having enormous search space with hybrid configuration. The experimental results are provided to show the effectiveness of the mixing collaborative and hybrid systems.

New Path Planning Algorithm based on the Visibility Checking using a Quad-tree on a Quantized Space, and its improvements (격자화된 공간상에서 4중-나무 구조를 이용한 가시성 검사를 바탕으로 한 새로운 경로 계획 알고리즘과 그 개선 방안들)

  • Kim, Jung-Tae;Kim, Dai-Jin
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.1
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    • pp.48-52
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    • 2010
  • In this paper, we introduce a new path planning algorithm which combines the merits of a visibility graph algorithm and an adaptive cell decomposition. We quantize a given map with empty cells, blocked cells, and mixed cells, then find the optimal path on the quantized map using a visibility graph algorithm. For reducing the number of the quantized cells we use the quad-tree technique which is used in an adaptive cell decomposition, and for improving the performance of the visibility checking in making a visibility graph we propose a new visibility checking method which uses the property of the quad-tree instead of the well-known rotational sweep-line algorithm. For the more efficient visibility checking, we propose two additional improvements for our suggested method. Both of them are used for reducing the visited cells in the quad-tree. The experiments for a performance comparison of our algorithm with other well-known algorithms show that our proposed method is superior to others.

Ultrastructural Studies for Protoplasts and Protoplast Fusion in Streptomyces lavendulae (Streptomyces levendulae의 원형질체와 원형질체 융합에 대한 미세구조)

  • 하영칠;홍순우;유진철;임헌만
    • Korean Journal of Microbiology
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    • v.24 no.3
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    • pp.197-203
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    • 1986
  • Morphology and ultrastructure of protoplast fusion mode in Streptomyces lavendulae were studied by scanning and transmission electron microscopy. The isolated protoplasts were stable in some degree in hypertonic solution except that several protoplasts showed irregular morphology. Fusion events were occurred as follows; contact zone, fusion zone and separation zone were appeared sequentially. After formation of the separation zone, cytoplasm and DNA from both parents were mixed eventually. In the contact zone, two menbranes were still separated by electron transparent space. The contact zone changed to fusion zone by formation of fusion membrane that phospholipid molecules of two membranes were rearranged. Thereafter, nonmembraneous separation zone was formed by disappearance of fusion membrane. These changes were characterized by successive changes in typical membrane structure in fusion areas and by a progressive loss of bispherical shape.

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A Study on the Dwellings of Korean Diaspora in Yunhaju of Russia (러시아 거주 고려인의 주거에 관한 연구 -연해주 (Yunhaju: 연해주) 지역을 중심으로-)

  • 이영심;조재순
    • Journal of the Korean housing association
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    • v.15 no.1
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    • pp.51-62
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    • 2004
  • Koreans had started moving to Yunhaju in Russia for escaping from the tyrannical rule and famine in 1860's in Korea. It had been veiled and nearly known about Korean's life there because of social and political situation of Russia until the Perestroyka. This study examined the dwellings of Korean Diaspora in Yunhaju through visiting their houses and having an interview. Results of research were as following: 1) Russian traditional houses which Koreans built was followed by Russian style basically and Koreans used the space slightly different way. Korean Diaspora have been adopted Russian life style with keeping their own traditional way of living. 2) Some Korean Diaspora still have been kept traditional heating system 'Ondol' in their houses until now in Yunhaju. Moreover over, it is known that people of Central Asia prefer to set 'Ondol' recently as a very specific and expensive heating system. 3) Korean's food style in Yunhaju is the one mixed with Russian, Korean, and Central Asian foods. This study could be a first step to supply for a basic information for studying of Korean Diaspora in Russia and it is needed to take more deep research in other areas in Russia.

An Analysis of Cell Loss Process in an ATM Network Under Partial Buffer Sharing Policy (ATM 전송망에서의 PBS를 이용한 셀 우선 순위 제어 방식의 연구)

  • 곽민곤;성수란;김종권
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.12
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    • pp.2328-2339
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    • 1994
  • The PBS(Partial Buffer Sharing) space priority mechanism is one of priority control methods which may improve the performance of a single server queueing system when mixed traffic with different performance requirements is applied to the system. This paper analyzes the cell loss behavior of PBS assuming loss sensitive traffic and delay sensitive traffic are applied to the system. To derive the successive cell loss probabilities. which are an important performance measure of realtime traffic, we develop a recursive algorithm. Performance results show the successive cell loss probabilities obtained by our method are lager than the probabilities derived from an independent cell loss assumption. These results may indicate the limitation of PBS for realtime traffic and the increase of the admissible load with the criterion of quality of service.

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Study of strength Development of Ultra High-Strength Concrete (초고강도 콘크리트의 강도발현에 관한 기초적 연구)

  • Min, Hong-Jun;Gong, Min-Ho;Lim, Nam-Gi;Lee, Young-Do;Jung, Sang-Jin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.11a
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    • pp.75-79
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    • 2006
  • Recently, more highly effective construction materials are needed for the reasonable and economical structure system is required as the construction structures become more multi storied, large-sized and diversified. That is to say, the highly qualified concrete is positively promoted as a part of plan to establish the effective space according to the dead load of structures and diminish of segment profile and to build up the economic structures. However, the high strength concrete has the problems such high brittleness and low ductility. Specially, for the high strength concrete, it has different strength from normal concrete as the internal temperature goes up steadily due to high heat of hydration by the quantities of highly level of cement, so the concrete which is mixed with various miscible materials is used. As the development and study for high strength concrete (more than $100N/mm^2$) is under way actively and the strength of high strength concrete increases, the strength different from the existing high strength concrete of ten than $100N/mm^2$, but the study for this is not adequate and indefinite. In addition, the study and report to apply the strength expression and analysis results of internal structure. Therefore, this study is an experiment about using the miscible materials affects what happens to the longitudinal physical property.

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Incompressible smoothed particle hydrodynamics modeling of thermal convection

  • Moballa, Burniadi;Chern, Ming-Jyh;Odhiambo, Ernest
    • Interaction and multiscale mechanics
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    • v.6 no.2
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    • pp.211-235
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    • 2013
  • An incompressible smoothed particle hydrodynamics (ISPH) method based on the incremental pressure projection method is developed in this study. The Rayleigh-B$\acute{e}$nard convection in a square enclosure is used as a validation case and the results obtained by the proposed ISPH model are compared to the benchmark solutions. The comparison shows that the established ISPH method has a good performance in terms of accuracy. Subsequently, the proposed ISPH method is employed to simulate natural convection from a heated cylinder in a square enclosure. It shows that the predictions obtained by the ISPH method are in good agreements with the results obtained by previous studies using alternative numerical methods. A rotating and heated cylinder is also considered to study the effect of the rotation on the heat transfer process in the enclosure space. The numerical results show that for a square enclosure at, the addition of kinetic energy in the form of rotation does not enhance the heat transfer process. The method is also applied to simulate forced convection from a circular cylinder in an unbounded uniform flow. In terms of results, it turns out that the proposed ISPH model is capable to simulate heat transfer problems with the complex and moving boundaries.

Accuracy of image registration for radiation treatment planning using a brain phantom

  • Jin, Ho-Sang;Suh, Tae-Suk;Song, Ju-Young;Juh, Ra-Hyeong;Kwark, Chul-Eun;Lee, Hyoung-Koo;Choe, Bo-Young
    • Proceedings of the KSMRM Conference
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    • 2002.11a
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    • pp.106-106
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    • 2002
  • Purpose: The purposes of our study are (1) to develop a brain phantom which can be used for multimodal image registration, (2) to evaluate the accuracy of image registration with the home-made phantom. Method: A brain phantom which could be used for image registration technique of CT-MR and CT-SPECT images using chamfer matching was developed. The brain phantom was specially designed to obtain imaging dataset of CT, MR, and SPECT. The phantom had an external frame with 4 N-shaped pipes filled with acryl rods for CT, MR imaging and Pb rods for SPECT imaging. 8 acrylic pipes were inserted into the empty space of the brain phantom to be imaged for geometric evaluation of the matching. Accuracy of image fusion was assessed by the comparison between the center points of the section of N-shaped bars in the external frame and the inserted pipes of the phantom. Technique with partially transparent, mixed images using color on gray was used for visual assessment of the image registration process.

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