• Title/Summary/Keyword: Space Rate

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A Certification Protocol based on Broadcast Invalidation Approach (브로드케스트 무효화 기법을 이용한 인증 프로토콜)

  • Sung-Ho Cho;Min-Goo Kang
    • Journal of Internet Computing and Services
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    • v.3 no.6
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    • pp.79-89
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    • 2002
  • The performance of OCC is very sensitive to the transaction abort rate, Even if the abort probability can be reduced by re-ordering, most of re-ordering schemes have space overhead in maintaining a graph or histories, In this paper, we proposed an efficient re-ordering scheme based on a broadcast invalidation mechanism. Our scheme, called CBI, can reduce the abort probability without space overhead in maintaining a graph or histories, By simulation studies, we showed that CBI reduced the abort rate and unnecessary operations, Additionally, we showed that CBI outperforms not only BTS but also TSH with low space overhead.

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Simultaneous Water and class I Methanol maser Survey of Shocker H2 Emitting regions

  • Lim, Wang-Gi;Lyo, A-Ran;Kim, Kee-Tae
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.118-118
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    • 2011
  • We executed a simultaneous survey of 22 GHz water maser and 44 GHz methanol maser toward 290 shocked $H_2$ emitting regions, which were identified from the galactic plane survey at $H_2$ 2.122 micrometer (UKIRT Widefield Infrared Survey for $H_2$; UWISH2). The primary goal of this observation is to characterize the H2 emission sources whether they are sincerely due to the outflows of young stellar objects or other shocked emission from older/evolved objects. We discovered 15 water maser sources and 15 methanol maser sources which provide the detection rate of around 5 percents. Most of detected sources have IRAS sources, infrared dark clouds, and/or submilimeter sources in the beam size of KVN single dish. In this poster, we will present the detailed results of our survey observation and discuss about the star formation rate in the galactic plane.

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ASCENT THERMAL ANALYSIS OF FAIRING OF SPACE LAUNCH VEHICLE

  • Choi Sang-Ho;Kim Seong-Lyong;Kim Insun
    • Bulletin of the Korean Space Science Society
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    • 2004.10b
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    • pp.239-242
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    • 2004
  • The fairing of the launch vehicles has a role of protecting the spacecraft from outer thermal, acoustical, and mechanical loads during flight. Among them, the thermal load is analyzed in the present study. The ascent thermal analyses include aerodynamic heating rate on every point of the fairing, heat transfer through the fairing and spacecraft, and the final temperature during ascent flight phase. A design code based on theoretical/experimental database is applied to calculate the aerodynamic heating rate, and a thermal math program, SINDA/Fluint, is considered for conductive heat transfer of the fairing. The results show that the present design satisfies the allowing temperature of the structure. Another important thermal problem, pyro explosive fairing separation device, is calculated because the pyro system is very sensitive to the temperature. The results also satisfies the pyro thermal condition.

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A Basic Study on the Fire Experiment of a Single Area for Fire Safety Design. (단일구획실험을 통한 화재안전설계에 관한 기초적 연구)

  • Kim, Dong;Yoon, Ung-Gi;Seo, Dong Goo;Kwon, Young Jin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2013.11a
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    • pp.110-111
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    • 2013
  • This research studies in the field of domestic fires are an issue in many scientific fire research as a research method to validate the domestic environment and ISO-9705 housing on the basis of experiments in virtual space by making a single fire compartment space for conducting experiments and Appearance of a fire occurring within each flammable Heat Release Rate analysis was carried out mainly. Placed within the space of one flammable HRR calculated as the sum of the number of single-room fire experiments conducted and the results compared with the value in comparing the conduct of fire locations and fire load within the building area of the future, the HRR value represents the change in domestic a consideration of the safety of the building is to propose matters.

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Variations of SCN Space in Metabolic Acidosis and Alkalosis in Rabbits (대사성 산증 및 알칼리증에 있어서 SCN 공간의 변화)

  • Earm, Yung-E;Nam, Kee-Yong
    • The Korean Journal of Physiology
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    • v.5 no.2
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    • pp.41-44
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    • 1971
  • Thiocyanate space was determined in 23 bilaterally nephrectomized rabbits in acute metabolic acidosis and alkalosis. Acid-base disturbances were induced by the infusion of 0.3 N HCI or 0.3 N NaOH solution intravenously with the rate of 1 ml/min for 40 to 60 minutes. The blood pressure was monitored throughout the experiment and no changes in blood pressure was confirmed. The following results were obtained. 1. In the saline infused control rabbits, PH was 7.385 with negligible change in pH after the infusion, SCN space was 23.6% of body weight. 2. In the metabolic acidosis group, pH dropped from 7.417 to 7 130 and SCN space was 22.8% of body weight and suggested a negligible change in the extracellular space volume. 3. In the metabolic alkalosis group, pH increased from 7.393 to 7.478 and SCN space was 25.7% of body weight which confirmed a significant increase in the extracellular space volume.

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The Hero's Journey of Animation from the Spatial Map Model (애니메이션 영웅서사의 공간지도 연구)

  • Shin, Yeonu
    • Journal of Korea Multimedia Society
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    • v.22 no.6
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    • pp.729-737
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    • 2019
  • This study defined the animation space as the concept of map based on the space of Joseph Campbell's heroic narrative. The space in which the animated character exists is an image symbolic language that reflects the inner and outer growth stages of the hero. I focused on the spatiality that plays the role of the power to lead the narrative and examined the meaning as the mediator that leads the heroic narrative. First, 6 spatial variables were derived by observing 'Hero's Journey 'which is used as a basis of US commercial animation scenario. Second, spatial variables are defined as 64 zones and proposed as 'Spatial Map Model of the Hero's Journey' (SMMH). Third, the character space of was applied to 'SMMH', and the change of space utilization rate and spatiality and the narrative meaning were analyzed. This study extended the narrative of animation space which was not actively studied to map concept. It is possible to provide a different viewpoint in animation production and research.

Analysis of Papers Published in the Journal of Astronomy and Space Sciences from 1984 to 2018

  • Jeon, Junhyeok;Kim, Yonggi
    • Journal of Astronomy and Space Sciences
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    • v.36 no.3
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    • pp.199-211
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    • 2019
  • This paper presents at the characteristics of publications in the Journal of Astronomy and Space Sciences from 1984 to 2018. Since its first publication, a total of 1,113 papers (~35 volumes) have been published up to December 2018. While the space astronomy field has made up a large portion of the total number of papers, the number of annually published papers in this field is decreasing. In contrast, the number of papers in the space environment field has been showing an increasing trend since 2013, accounting for more than 30% of the annual publications. The participation rate of foreign researchers has been maintained at greater than 20% since 2012. Despite the decrease in the number of paper per year, there are positive developments including sustained foreign researcher participation at greater than 20% and improvements in the impact factor. We believe that JASS has the potential to enter the distinguished level of international academic journals following a well-developed future road map.

Evaluation of Creative Space Efficiency in China' Provinces Based on AHP Method

  • Hu, Shan-Shan;Kim, Hyung-Ho
    • International journal of advanced smart convergence
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    • v.9 no.4
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    • pp.52-61
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    • 2020
  • The AHP method was used in 30 provinces of China to construct the index system of creative space efficiency evaluation and determine the weight of each index. The fuzzy comprehensive evaluation method was further used to score the indexes at all levels, and then the total efficiency score was sorted. The purpose of this study is to adjust the regional layout of creative space reasonably and implement financial policies accurately through the evaluation of the efficiency of creative space. The results is ranking top in weight of several indicators, which include the number of incubated Startups, the number of innovation and entrepreneurship mentors, the survival rate of incubator, the innovative training activities, etc. It was also found that Beijing, Shanghai, Jiangsu, Guangdong and Zhejiang ranked first in the score of creative space efficiency. This study is meaningful in that it was In order to effectively solve the problem of the imbalance of the creative space efficiency in China's province, by coordinating the regional pattern, establishing a sound service system and improving the efficiency evaluation system.

Absorption Characteristics of Perforated Environment Friendly Sound Absorbing Board using Hwangto (황토를 이용한 친환경 유공 흡음보드의 흡음특성)

  • Kim, Sun-Woo;Park, Hyeon Ku
    • KIEAE Journal
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    • v.11 no.1
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    • pp.3-8
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    • 2011
  • Sound absorbing materials used for lightweight panels and interior material are mainly made of fibroid material such as glass wool or rock wool. However these fiber type sound absorbing materials have some problems such that sound absorption could be decreased as time goes by because of durability. In addition, dust scattering from fiber type material can cause another problem in health. In this point of view, this study aims to develop environment friendly sound absorbing material using Hwangto(so called loess or yellow soil), a traditional housing material. Hwangto is natural housing material in Korea and generally known for improving indoor air quality. Hwangto panel is made to construct on the floor, wall and ceiling, and expected that there is not enough absorption. Present study tried to develop environment friendly sound absorbing material that has high sound absorption performance with good environment performance in terms of air quality. Pore rate was designed to maximize the absorption in the specific frequency bands, and two kinds of backing space were applied in order to see the effect of backing space. As a result peak frequency that has maximum absorption is going high as the pore rate is increased. The backing space provides more absorption and makes the peak frequency down to low.

Estimation of Allowable Path-deviation Time in Free-space Optical Communication Links Using Various Aircraft Trajectories

  • Kim, Chul Han
    • Current Optics and Photonics
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    • v.3 no.3
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    • pp.210-214
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    • 2019
  • The allowable path-deviation time of aircraft in a free-space optical communication system has been estimated from various trajectories, using different values of aircraft speeds and turn rates. We assumed the existence of a link between the aircraft and a ground base station. First, the transmitter beam's divergence angle was calculated through two different approaches, one based on a simple optical-link equation, and the other based on an attenuation coefficient. From the calculations, the discrepancy between the two approaches was negligible when the link distance was approximately 110 km, and was under 5% when the link distance ranged from 80 to 140 km. Subsequently, the allowable path-deviation time of the aircraft within the tracking-error tolerance of the system was estimated, using different aircraft speeds, turn rates, and link distances. The results indicated that the allowable path-deviation time was primarily determined by the aircraft's speed and turn rate. For example, the allowable path-deviation time was estimated to be ~3.5 s for an aircraft speed of 166.68 km/h, a turn rate of $90^{\circ}/min$, and a link distance of 100 km. Furthermore, for a constant aircraft speed and turn rate, the path-deviation time was observed to be almost unchanged when the link distance ranged from 80 to 140 km.