• Title/Summary/Keyword: Re-Entry

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Long-term evaluation of the bony regeneration following the guided tissue regeneration (차단막을 이요한 치조골재생의 장기적 평가)

  • Choi, Jeom-Il;Kim, Sung-Jo;Kim, Tae-Kyu
    • Journal of Periodontal and Implant Science
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    • v.26 no.2
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    • pp.350-355
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    • 1996
  • The present study was performed to evaluate the amount of bony regeneration following the guided tissue regeneration(GTR). Re-entry procedure has been performed at 1 year following the GTR with Gore-tex membranes on the furcal defects and the amount of bony regeneration was measured. Sites treatedwith open flap procedures were used as controls. The results reveated that significant amount of bone could be regenerated through the GTR procedures compared with convention flap procedures.

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Investigation of Single Phase Frictional Pressure Loss in Circular Micro Tubes

  • Han Dong-Hyouck;Lee Kyu-Jung
    • Journal of Mechanical Science and Technology
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    • v.20 no.8
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    • pp.1284-1291
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    • 2006
  • Single phase pressure drops in micro tubes were investigated through an experimental measurement and a numerical simulation. Experimental Po was obtained in circular micro tubes with 87 and $118{\mu}m$ diameter with distilled water. Experiments were carried out in laminar flow region with varying the Re 15-450 for the $87{\mu}m$ diameter tubes and 60-1300 for the $118{\mu}m$ diameter tube. No early transition from laminar to turbulent flow was detected for the experimental range. The computational estimation of pressure drop in the $87{\mu}m$ diameter tube was performed with the aid of CFD software. Boundary conditions from experiments were used for the numerical simulation. The results of experimental and numerical studies showed a good agreement with the conventional macro theory.

A Study on the Enhancement of Detection Performance of Space Situational Awareness Radar System

  • Choi, Eun-Jung;Lee, Jonghyun;Cho, Sungki;Moon, Hyun-Wook;Yum, Jea-Myong;Yu, Jiwoong;Park, Jang-Hyun;Jo, Jung Hyun
    • Journal of Astronomy and Space Sciences
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    • v.35 no.4
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    • pp.279-286
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    • 2018
  • Radar sensors are used for space situational awareness (SSA) to determine collision risk and detect re-entry of space objects. The capability of SSA radar system includes radar sensitivity such as the detectable radar cross-section as a function of range and tracking capability to indicate tracking time and measurement errors. The time duration of the target staying in a range cell is short; therefore, the signal-to-noise ratio cannot be improved through the pulse integration method used in pulse-Doppler signal processing. In this study, a method of improving the signal-to-noise ratio during range migration is presented. The improved detection performance from signal processing gains realized in this study can be used as a basis for comprehensively designing an SSA radar system.

A New Grid-Based Monte Carlo Code for Raman Scattered He II: Preliminary Results

  • Chang, Seok-Jun;Choi, Bo-Eun;Lee, Hee-Won
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.85.2-85.2
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    • 2019
  • We developed a new grid-based Monte Carlo code to trace far UV He II line photons that are incident on a thick H I region and subsequently transferred through Rayleigh and Raman scattering with atomic hydrogen. In particular, we consider a neutral region that is moving away from the He II emission source which is either monochromatic or is described by a Gaussian profile. The resultant Raman scattered He II line profiles from a monochromatic source are characterized by a double peaked core part with an extended Raman red tail that is attributed to multiple re-entry events. Complicated behaviors are observed in the case of a Gaussian He II source including the formation of a secondary red peak near the Balmer center dependent on the H I column density. A preliminary application of our results to the CFHT data of the planetary nebula IC 5117 is presented.

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A Study of the Flow Phenomenon of Water in a Channel with Flat Plate Obstruction Geometry at the Entry

  • Khan, M.M.K.;Kabir, M.A.;Bhuiyan, M.A.
    • Journal of Mechanical Science and Technology
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    • v.17 no.6
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    • pp.879-887
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    • 2003
  • The flow in a parallel walled test channel, when obstructed with a geometry at the entrance, can be forward, reverse and stagnant depending on the position of the obstruction. This interesting flow phenomenon has potential benefit in the control of energy and various flows in the process industry In this experiment, the flat plate obstruction geometry was used as an obstruction at the entry of the test channel. The parameters that influence the flow inside and around the test channel were the gap (g) between the test channel and the obstruction geometry, the length (L) of the test channel and the Reynolds number (Re). The effect of the gap to channel width ratio (g/w) on the magnitude of the velocity ratio (V$\_$i/ / V$\_$o/ : velocity inside/ velocity outside the test channel) was investigated for a range of Reynolds numbers. The maximum reverse flow observed was nearly 20% to 60% of the outside velocity for Reynolds number ranging from 1000 to 9000 at g/w ratio of 1.5. The maximum forward velocity inside the test channel was found 80% of the outside velocity at higher g/w ratio of 8. The effect of the test channel length on the velocity ratio was investigated for different g/w ratios and a fixed Reynolds number of 4000. The influence of the Reynolds number on the velocity ratio is also discussed and presented for different gap to width ratio (g/w). The flow visualisation photographs showing fluid motion inside and around the test channel are also presented and discussed.

Fifty Years of Scientific Ocean Drilling (1968-2018): Achievements and Future Direction of K-IODP (해양 과학시추 50년 (1968-2018): 한국의 성과 및 미래 방향)

  • KIM, GIL YOUNG
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.24 no.1
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    • pp.30-48
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    • 2019
  • The year 2018 is the $50^{th}$ anniversary of scientific ocean drilling. Nevertheless, we know more about the surface of the moon than the Earth's ocean floor. In other words, there are still no much informations about the Earth interior. Much of what we do know has come from the scientific ocean drilling, providing the systematic collection of core samples from the deep seabed. This revolutionary process began 50 years ago, when the drilling vessel Glomar Challenger sailed into the Gulf of Mexico on August 11, 1968 on the first expedition of the federally funded Deep Sea Drilling Project (DSDP). DSDP followed successively by Ocean Drilling Program (ODP), Integrated Ocean Drilling Program (old IODP), and International Ocean Discovery Program (new IODP). Concerning on the results of scientific ocean drilling, there are two technological innovations and various scientific research results. The one is a dynamic positioning system, enables the drilling vessel to stay fixed in place while drilling and recovering cores in the deep water. Another is the finding of re-entry cone to replace drill bit during the drilling. In addition to technological innovation, there are important scientific results such as confirmation of plate tectonics, reconstruction of earth's history, and finding of life within sediments. New IODP has begun in October, 2013 and will continue till 2023. IODP member countries are preparing for the IODP science plan beyond 2023 and future 50 years of scientific ocean drilling. We as IODP member also need to participate in keeping with the international trend.

A Study on the Welfare Policy of Career Interrupted Women (경력단절여성의 복지정책에 관한 연구)

  • Kyung-Hwa, Lee
    • Journal of Advanced Technology Convergence
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    • v.1 no.2
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    • pp.57-62
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    • 2022
  • In order to support women with career breaks to re-enter the labor market, it is not only necessary to discover and select promising jobs, but also to provide objective and accurate job information on selected promising jobs so that women with career breaks can make reasonable career choices. need arises. It can be pointed out that the government support course has no burden of tuition compared to the general course, and because the quality of education is high, it is possible to select trainees with a high willingness to find employment through competition in the recruitment process. In addition, the government support process secures relatively high-quality programs and instructors, increasing trainees' concentration, satisfaction, and willingness to find a job. Job literacy and employment preparation education are obligatory, job design support through job counseling, and continuous follow-up support. The system also works. Accordingly, if systematic and continuous development and support are made in the process of selecting promising occupations for women with career breaks and designing education and training programs, it is expected that women with career breaks will be more active in their re-entry into the labor market.

Southeast Asian Studies: Insiders and Outsiders, or is Culture and Identity a Way Forward?

  • King, Victor T.
    • SUVANNABHUMI
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    • v.8 no.1
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    • pp.17-53
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    • 2016
  • Debates continue to multiply on the definition and rationale of Southeast Asia as a region and on the utility of the multidisciplinary field of area studies. However, we have now entered a post-colonialist, post-Orientalist, post-structuralist stage of reflection and re-orientation in the era of globalization, and a strong tendency on the part of insiders to pose these issues in terms of an insider-outsider dichotomy. On the one hand, the study of Southeast Asia for researchers from outside the region has become fragmented. This is for very obvious reasons: the strengthening and re-energizing of academic disciplines, the increasing popularity of other non-regional multidisciplinary studies, and the entry of globalization studies into our field of vision. On the other hand, how has the local Southeast Asian academy addressed these major issues of change in conceptualizing the region from an insider perspective? In filling in and giving substance to an outsider, primarily Euro-American-Australian-centric definition and vision of Southeast Asia, some local academics have recently been inclined to construct Southeast Asia in terms of the Association of Southeast Asian Nations (ASEAN): a nation-state-based, institutional definition of what a region comprises. Others continue to operate at a localized level exploring small-scale communities and territories, while a modest number focus on sub-regional issues (the Malay-Indonesian world or the Mekong sub-region are examples). However, further reflections suggest that the Euro-American-Australian hegemony is a thing of the past and the ground has shifted to a much greater emphasis on academic activity within the region. Southeast Asia-based academics are also finding it much more important to network within the region and to capture, understand, and analyze what Chinese, Japanese, and Korean scholars are saying about Southeast Asia, its present circumstances and trajectories, and their increasingly close involvement with the region within a greater Asia-Pacific rim. The paper argues that the insider-outsider dichotomy requires considerable qualification. It is a neat way of dramatizing the aftermath of colonialism and Orientalism and of reasserting local priorities, agendas, and interests. But there might be a way forward in resolving at least some of these apparently opposed positions with recourse to the concepts of culture and identity in order to address Southeast Asian diversities, movements, encounters, hybridization, and hierarchies.

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A Study on the Characteristics of Space Forms in Performing Arts Centers for Performance Types (공연의 형식에 따른 현대공연장 공간구성 특성에 관한 연구)

  • Kim, Sung-Kee
    • Korean Institute of Interior Design Journal
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    • v.21 no.1
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    • pp.195-202
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    • 2012
  • This study aimed to analyze the types and characteristics of space forms according to performance types in the space of performing arts centers through the cases of modern performing arts centers. As for the space forms according to the performance forms, the performing arts centers devoted to dramas made a small space or turned into multi-purpose ones entering the modern days. Added to the proscenium, the main stage, was the back stage for the stage background. The area of the stage and auditorium grew similar with some kind of separation between the stage and audience. The concert halls have close relationships with the audience and their stage contacts the auditorium on many sections. The stage space is smaller than the auditorium and usually either the complex or entry type. In the opera theater, they commonly create a space for social gathering in addition to the main stage of proscenium, back stage, side stage and auditorium. They're also distinct from other performing centers for having an orchestra pit between the stage and audience. The stage is twice as big as the auditorium and the separate type. In today's performing arts centers, the sizes of the stage and auditorium can vary widely, and the performances of many different genres are put to multiple purposes.

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Assessment of Health and Nutritional Status of North Koreans Utilizing an Exhaustive Literature Search and Survey (문헌과 이탈 귀순자 설문조사를 통해 본 북한인의 보건영양상태)

  • 장남수
    • Journal of Nutrition and Health
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    • v.31 no.8
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    • pp.1338-1346
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    • 1998
  • North Korea has been experiencing a serious food shortage. However, the extent and magnitude of malnutrition and health problems are virturally unknown because a nationwide food and nutritional survey has never been conducted. To get a better udnerstanding of the situation., an exhaustive literature search on the health and nutritiona conditions of North Koreans was performed. We also obtained anthropometric data on 274 North Korean Defectors who are recently resettlers in the South. Some(137) measurements were taken at the time of entry to the South, and the remaining data was from the health and nutrition mail survey conducted by us on North Korean refugeee re-settlers. Health and inutritional status of North Koreans was found to be less than desirable as shown in high infant mortality rates, high mortality and morbidity rates of malnutriton-related infectious deseases, and smaller body sizes. Striking differences were noted in all of the above health and nutrition indicators between north and South Koreans. Considering the fact that North and South Koreans are homogeneous in their genetic back-ground, ours study results clearly demonstrate that the health and nutrition of North Koreas has deteriorated with the dhronic food shortage, which might have sorsened with a recent food crissi. The smaller and thinner adult stature proevailing in North Korea could play a significant negative role in the country's economy, since lower lean body mass has been associated with reduced work productivity that could hinder economic growth and development.

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