http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Delay Minimization Algorithm with a Predefined Conference Time Guarantee
Dongsu Seong,Keonbae Lee 한국멀티미디어학회 2009 한국멀티미디어학회 국제학술대회 Vol.2009 No.-
Ad-hoc hierarchical conference may cause the transmission delay between the terminal nodes. This problem can be solved by constructing the conference such that each terminal node has many neighboring terminal nodes as possible. This method minimizes the number of hops between terminal nodes in a conference, but it may deplete quickly the computing resources and powers since the nodes should process a great deal of media traffic from its neighboring nodes. Therefore the predefined conference time may be not guaranteed in a mobile environment. There is a trade-off between the scheme to reduce the transmission delay and the scheme to reduce the resource consumption rate. This paper introduces a algorithm for minimizing the media delay with a guarantee of the predefined conference time.
최단 거리 단말기의 소개를 이용하는 계층 회의 구성 방법
성동수(Dongsu Seong) 한국정보기술학회 2012 한국정보기술학회논문지 Vol.10 No.8
The multipoint conference is expected to be one of the fundamental applications in ubiquitous environment, and hierarchical conference can be used well in this environment. The multipoint conference system using the endpoint mixing scheme causes the media data delay problem since the media data go through the hierarchical structure. In this paper, we propose an algorithm which minimizes the distance between terminals, and which considers the computing resource. When a new participant wants to join the ongoing hierarchical conference, our algorithm introduces a proper terminal in the conference and new participants terminal sends a call request to the introduced terminal which has the minimum distance from new participants terminal among the selected terminals with the computing resource consideration. As the experimental results with the proposed method, the hierarchical conference can be organized efficiently comparatively with the earlier schemes on the basis of media delay point of view because the average path distance between terminals can be reduced.
계층적 다자간 회의에서 평균 경로 거리를 고려한 회의구성 알고리즘
성동수(Dongsu Seong) 한국정보기술학회 2011 한국정보기술학회논문지 Vol.9 No.9
The multipoint conference in ubiquitous environment is expected to be one of the fundamental applications for various services, and ad-hoc hierarchical conference can be used well in this environment. When a new participant with a multimedia terminal wants to join an ad-hoc wireless hierarchical conference, our algorithm introduces a proper terminal in the conference and new participant's terminal sends a call request to the introduced terminal. The proposed algorithm selects adequate terminals in the conference to consider each terminal’s computing resources and introduces the terminal to minimize the average path distance between terminals among the selected terminals. The conference can be organized more efficiently in the environment to organize an ad-hoc hierarchical conference in comparison with the earlier scheme.
Dongsu Choi,Soong-Taek Hwang,Yeon-Ki Kim,Seong-Han Sohn 한국식물학회 2018 Journal of Plant Biology Vol.61 No.6
Submergence harms plants by limiting gasexchange and decreasing incoming light. Upon prolongedflooding, deepwater rice (Oryza sativa) escapes completesubmergence by rapid stem growth, but the mechanism ofstem elongation in the early stages following submergenceremains unclear. To elucidate changes in gene expressionduring early submergence-induced stem elongation, weperformed transcriptome analysis using microarray system indeepwater rice. We compared gene expression between thecontrol (0 h) and 1, 4 hour after submergence. We found 586and 1,353 genes for Sub 1 h and 4 h treatments each thatwere up-regulated by at least two-fold, compared to thecontrol (P < 0.05), submergence up-regulated gene expressionrelated to at least 10 independent biological processes. Expression of deepwater rice genes related to energy productionthrough fermentation increased with time after submergence,which likely ensures sufficient energy for rapid stemelongation. We provide the first report of initial and overallexpression of deepwater rice genes related to the responsespecific to submergence escape.
QUASI-SPHERICAL, TIME-DEPENDENT VISCOUS ACCRETION FLOW: ONE-DIMENSIONAL RESULTS
Lee, Seong-Jae,Ryu, Dongsu,Chattopadhyay, Indranil IOP Publishing 2011 The Astrophysical journal Vol.728 No.2
<P>We investigated the instability of advective accretion flow as a consequence of angular momentum transfer in one-dimensional, quasi-spherical transonic accretion flow around a non-rotating black hole. The code is designed to include the effects of viscosity; the hydrodynamics component preserves angular momentum strictly with Lagrangian and remap method in the absence of viscosity, while the viscosity component updates viscous angular momentum transfer through the implicit method. We performed two tests to demonstrate the suitability of the code for accretion study. First, we simulated the inviscid, low angular momentum, transonic accretion flow with shocks around a black hole, and then the subsonic, self-similarADAF solution around a Newtonian object. Both simulations fitted the corresponding analytical curves extremely well. We then simulated a rotating, viscous, transonic fluid with shocks. We showed that for low viscosity parameter, stable shocks at larger distance are possible. For higher viscosity parameter, more efficient angular momentum transfer in the post-shock disk makes the shock structure oscillatory. Moreover, as the shock drifts to larger distances, a secondary inner shock develops. We showed that the inner shock is the direct consequence of the expansion of the outer shock, as well as the creation of regions with partial derivative l/partial derivative r < 0 due to more efficient angular momentum transfer near the inner sonic point. We showed that all disk parameters, including emissivity, oscillate with the same period as that of the shock oscillation. Our simulation may have implications for low frequency quasi-periodic oscillations, e.g., GRO J1655-40 and XTE J1550-564.</P>
IP기반의 차세대 무선네트워크에서 끊김없는 이동성지원을 위한 인증기법
한동수 ( Dongsu Han ),안성진 ( Seong-jin Ahn ),정종필 ( Jongpil Jeong ) 한국정보처리학회 2011 한국정보처리학회 학술대회논문집 Vol.18 No.1
최근 스마트폰의 보급에 따라 이동통신에서의 무선 데이터망에 대한 수요가 늘어남에 따라서 이를 보완하기 위해서 무선 사업자들은 WiFi와 같은 대체 통신 인프라를 늘려 나가고 있다. 향후 4G라고불리는 NGN에서는 음성을 비롯한 모든 정보들이 IP망에서 동작하게 될 것이다. 이러한 3G망과 GSM 그리고 WiFi, Wibro 등이 복합적으로 구성되어 있는 IP 네트워크에서 사용자로 하여금 끊김없는 서비스를 유지하려면 각 망간의 수평이동이 원활하게 되어야 하며 이를 위한 다양한 연구가 진행되어 왔다. 본 논문에서는 빠른 핸드오프 성능을 높일 수 있는 인증 개념을 도입하고자 한다. 인증하는 시간을 줄임으로서 끊김없는 서비스를 지원하는데 많은 도움이 될 것이다.