• Title/Summary/Keyword: VEGA

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The near infrared image of GRB100205A field

  • Kim, Yongjung;Im, Myungshin
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.82.1-82.1
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    • 2012
  • GRB100205A is a Gamma Ray Burst (GRB) which is suspected to be at redshift z=11-13 due to its very red H-K color($(H-K)_{vega}=2.1{\pm}0.5$). We observed a field centered at GRB100205A with Wide Field Camera (WFCAM) at United Kingdom Infrared Telescope (UKIRT) in Hawaii, in order to search a quasar that could be located around the GRB. The images were obtained in J, H, and K filters covering a square area of $0.78deg^2$. Our J-, H-, and K-band data reach the depths of 22.5, 22.1, and 21.0 mag (Vega) at $5{\sigma}$, respectively. Also using z-band image observed by CFHT, we find 8 candidates that have colors consistent with a quasar at z=11-13(non-detection in z-, J-band and $(H-K)_{vega}$ > 1.6). However, the shallow depths of J-, H-band are not enough to verify their true nature. Instead, we identify many red objects to be old or dusty galaxies at $z{\geq}3$. The number density of such objects appears about twice or more than that of the field of Cosmological Evolution Survey (COSMOS) and Ultra Deep Survey (UDS) of UKIRT Infrared deep sky survey (UKIDSS). On scales between 0.18' and 15' the correlation function is well described by a power law with an exponent of ${\approx}-0.9$ and this implies that those objects are like galaxies. It is interesting that many red galaxies exist in the region where the GRB was detected.

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Improving TCP-Vegas Performance over Mobile Ad-hoc Networks (이동 애드혹 네트워크에서의 TCP-Vegas 성능향상 기법)

  • Bae Han-Seok;Song Jeom-Ki;Kim Dong-Kyun;Park Jung-Soo;Kim Hyoung-Jun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.3A
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    • pp.221-231
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    • 2006
  • TCP is needed as a transport protocol to provide reliable end-to-end message delivery for MANETs in order to achieve a smooth integration with the fixed Internet. Particularly, TCP has its variants, namely TCP-Reno and TCP-Vegas. However, there has been no research work on extensive performance comparison of TCP-Reno and TCP-Vegas over AODV and OLSR. This paper is the first trial to perform the research by using ns-2 simulator. Through the extensive simulations, we found that which to select among routing protocols is more important than which to select among TCP variants, because the performance difference between TCP-Reno and TCP-Vegas over uy selected routing protocol is not so much outstanding. Particularly, TCP-Vegas relies on an accurate BaseRTT estimation in order to decide the sending rate of a TCP Sender. However, it cannot be directly applied to MANET because a route change makes the Base an used over a Previous Path obsolete. Therefore, we propose a technique for improving the performance of TCP-Vegas by considering the route change, and show the performance improvement through simulation study.

A Study on the Character of Postpartum Women by Factor AA in 7-Zone-Diagnostic System (7구역 진단기의 Factor AA를 통한 산모의 특성 연구)

  • Song, Yun-Hui;Kim, Tae-Hee
    • The Journal of Korean Obstetrics and Gynecology
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    • v.21 no.3
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    • pp.132-142
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    • 2008
  • Purpose: This research was designed to study that VEGA DFM 722 is proper index in postpartum women. Methods: The subjects were 81 postpartum women who admitted for postpartum care in Oriental Hospital of Woosuk University from 20, May 2005 to 28, October 2005 and 83 general women who taken Medical Health Examination from 29, January 2005 to 22, July 2006. The women took the test of VEGA DFM 722 and CBC. The SPSS 12.0 for windows was used to analyse the data and the independent samples t-test and paired samples t-test were used to verify the results. Results: The following results were obtained 1. The heights of zone 1, 2, 3 of postpartum women group significantly higher than that of general women group. The height of zone 6 of postpartum women group significantly higher than that of general women group. But, there were no significant differences in the heights of zone 4, 5, 7. 2. The heights of zone 1, 2, 3 of second test significantly lower than that of first test in postpartum women. But, there were no significant differences in the heights of zone 4, 5, 6, 7. Conclusion: The results suggest that postpartum women has upper heat and lower cold compared with general women. And after oriental postpartum care, disparity in upper heat and lower cold was decreased in postpartum women.

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Throughput analysis of RTP-TCP coexistence network (RTP-TCP가 공존하는 네트워크의 Throughput 분석)

  • 김석후;채현석;최명렬
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.10e
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    • pp.682-684
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    • 2002
  • 본 논문에서는 RTP와 TCP가 공존하는 네트워크에서 RTP 패킷의 크기, interval,전송라인의 대역폭, Queue의 크기, delay의 변화에 따라 throughput의 특징에 대하여 알아보기 위해서 ns(network simulator)를 이용하여 RTP, TCP_Reno, TCP_Vegas로 구성된 네트워크를 구성하고 시뮬레이션을 통해서 throughput의 특징 및 원인을 분석했다.

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A Study on the Clinical Use of 7-zone-Diagnostic System (2) - the Comparative Analysis of the Rule and the Decipher for each Equipment - (7구역진단기의 임상응용에 대한 고찰 (2) - 각 제품에 따른 원리와 판독의 비교 -)

  • Song, Beom-Yong
    • Journal of Acupuncture Research
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    • v.23 no.5
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    • pp.11-21
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    • 2006
  • The 7-zone-diagnostic system(ABR-2000, BIO MEDIC 700Plus, CP-6000A, OMD 3000, VEGA-DFM 722) is a diagnostic device which applies pulse signals to predetermined bodily locations. Applying alternating positive and negative stress to tissues with positive and negative pulses first manifests itself as negative and positive wave forms. This system make a diagnosis of functional disorder or some typical organic diseases include stress of the mind or the body, and the energetic situation, reserves. We are known a disorder or disease throw the result charts. And these result represents various characteristic signals are assisted diagnosis and care. These result chart contains disorder flow wave forms and some valuable diagnostic hints or marks. But we have several various products for the 7-zone-diagnostic system. I think that we need the comparative analysis of the general rule and the decipher for each equipment. Because these letters(marks) each product are different, we necessary various plentiful research and suitable statistics in these points. And we must carry out many various research in the future.

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Managerial Ability, Managerial Incentives and Firm Performance: Empirical Evidence from Vietnam

  • PHAN, Nghi Huu
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.4
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    • pp.193-200
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    • 2021
  • This study investigates the impact of managerial ability and managerial incentives on firm performance. In particular, it studies how managerial ability factor can exert significant influence on the profitability and the risk of firms. By doing this, the study can provide several policy implications about how managerial ability can influence firm decisions and its corresponding business policies. Data of the study was collected from the Annual Enterprises Survey (AES), which is conducted by the General Statistics Office of Vietnam (GSO) during the 2009-2013 period. After removing firms with insufficient financial information, our final dataset includes over 50,000 firms in Vietnam. The main result of the study shows that there is a significant and positive relationship between managerial ability and firm leverage. This finding indicates that managerial ability significantly plays an important role in making financial decisions. In addition, our study provides empirical evidence about the causal relationship between managerial compensation and firm risk-taking behavior. Specifically, we find that firm risks are significantly associated with compensation schemes including lower delta and higher vega. In other words, our study implies that the sensitivity of CEO wealth to stock volatility can positively affect both delta and vega or managerial incentives schemes.

WELL-POSEDNESS FOR THE BENJAMIN EQUATIONS

  • Kozono, Hideo;Ogawa, Takayoshi;Tanisaka, Hirooki
    • Journal of the Korean Mathematical Society
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    • v.38 no.6
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    • pp.1205-1234
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    • 2001
  • We consider the time local well-posedness of the Benjamin equation. Like the result due to Keing-Ponce-Vega [10], [12], we show that the initial value problem is time locally well posed in the Sobolev space H$^{s}$ (R) for s>-3/4.

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Adaptive control for robot manipulators exeeuting fine motion tasks

  • Parra-Vega, Vicente;Arimoto, Suguru
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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    • pp.183-188
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    • 1994
  • A passivity-based adaptive controller for robots executing fine motion tasks is proposed. The robot dynamics is modelled such that it is subject to holonomic constraints and hence it can be treated as a particular case of constrained motion tasks. Energy-motivated stability analysis is used to conclude the asymptotic stability. Remarks regarding the structure of the controller are given. A computer simulations study is presented and a robust constraint stabilization algorithm is also proposed.

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Collaborative Visualization of Warfare Simulation using a Commercial Game Engine (상업용 게임 엔진을 활용한 전투 시뮬레이션 결과의 협업 가시화)

  • Kim, Hyungki;Kim, Junghoon;Kang, Yuna;Shin, Suchul;Kim, Imkyu;Han, Soonhung
    • Journal of the Korea Society for Simulation
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    • v.22 no.4
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    • pp.57-66
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    • 2013
  • The needs for reusable 3D visualization tool has been being raised in various industries. Especially in the defense modeling and simulation (M&S) domain, there are abundant researches about reusable and interoperable visualization system, since it has a critical role to the efficient decision making by offering diverse validation and analyzing processes. To facilitate the effectiveness, states-of-the-arts M&S systems are applying VR (Virtual Reality) or AR (Augmented Reality) technologies. To reduce the work burden authors design a collaborative visualization environment based on a commercial game engine Unity3D. We define the requirements of the warfare simulation by analyzing pros and cons of existing tools and engines such as SIMDIS or Vega, and apply functionalities of the commercial game engine to satisfy the requirements. A prototype has been implemented as the collaborative visualization environment of iCAVE at KAIST, which is a facility for immersive virtual environment. The facility is intraoperative with smart devices.

Performance Evaluation for TCP/IP over UBR (UBR 위에서 동작하는 TCP/IP 성능 평가)

  • Ahn, Sung-Soo;Yu, Hyung-Sik;Whang, Sun-Ho;Lee, Jun-Won;Kim, Sung-Un
    • Journal of KIISE:Information Networking
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    • v.27 no.1
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    • pp.76-87
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    • 2000
  • ATM is a key technology of integration of multimedia service. Recently, Many study have been concentrated on performance testing for evaluation network performance are stronger everyday. The performance testing is on evaluation of maximal throughput of network by measuring and analyzing of various performance parameters. There are two ways to test ATM network performance; one is using QoS in cell level on the point of network's view, and the other is using metric in frame level in the point of user's view. And, the standardization process is also under way. In this paper, we derive a performance requirement of TCP in TCP/IP data transmission over ATM UBR service. By applying the derived requirements to ATM and packet networks, we evaluate the performance of TCP over UBR based on the result of our simulations. Therefore, we evaluate the result of simulation and find degradation of network throughput by interaction between TCP congestion control and ATM cell drop policy. So we suggest the accelerated Vegas that modify traditional TCP Vegas in congestion control mechanism for batter network throughput.

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