• Title/Summary/Keyword: sweeping

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The Multistakeholder Model of Internet Governance (인터넷 거버넌스 모델로서의 멀티스테이크홀더)

  • Lee, Young-Eum
    • Review of Korean Society for Internet Information
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    • v.14 no.3
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    • pp.21-34
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    • 2013
  • The multistakeholder model of Internet governance is based on the belief that the stakeholder groups should be able to agree on the rules and principles in governing the Internet space. The global expansion of the sweeping influence of the Internet has heightened the awareness of international governments on the importance of Internet governance, but since the Internet has developed mostly through voluntary participation by various groups, the organization with the greatest ability to manage the Internet space currently is ICANN(Internet Corporation for Assigned Names and Numbers), the U.S. based organization that manages the assignment of Internet domain names and IP addresses. Although ICANN has attempted to globalize its operation, governments in some nations are voicing dissatisfaction over the fact that the voice of the governments are not adequately represented within ICANN. This paper examines how the concept of multistakeholderissm has been used in WSIS(World Summit on Information Society), ICANN(Internet Corporation for Assigned Names and Numbers) and the ITU(International Telecommunication Union) as an important principle in emphasizing their roles in Internet governance.

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Thermal-Hydraulic Analysis of A Wire-Spacer Fuel Assembly

  • Ahmad, Imteyaz;Kim, Kwang-Yong
    • 유체기계공업학회:학술대회논문집
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    • 2004.12a
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    • pp.473-478
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    • 2004
  • This work presents the Thermal Hydraulic analysis has been performed for a 19-pin wire-spacer fuel assembly using three-dimensional Reynolds-averaged Navier-Stokes equations. SST model is used as a turbulence closure. The whole fuel assembly has been analyzed for one period of the wire-spacer using periodic boundary condition at inlet and outlet of the calculation domain. The overall results far a preliminary calculation show a good agreement with the experimental observations. It has been found that the major unidirectional flows are the axial velocity in sub-channels and the peripheral sweeping flows and the velocities are found to be following a cyclic path of period equal to the wire-wrap pitch. The temperature is found to be maximum in the central region and also, there exist a radial temperature gradient between the fuel rods. The major advantage of performing this kind of analysis is the prediction of thermal-hydraulic behavior of a fuel assembly with much ease.

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Damage Detection Method for Bridge Structures Using Hilbert-Huang Transform Technique (Hilbert-Huang Transform을 이용한 교량구조물의 손상추정기법)

  • 윤정방;장신애;심성한;이종재
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2002.10a
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    • pp.453-458
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    • 2002
  • A recently developed Hilbert-Huang transform (HHT) technique is applied to the detection of the damage locations of bridge structures. The HHT may be used to identify the locations of damages which exhibit nonlinear and non-stationary behavior, since the instantaneous frequency characteristics of the measured signal can be analyzed by the HHT. Numerical simulations were conducted on two bridge systems with damages using controlled excitations with sweeping frequency. Nonlinear plastic model using a gap element is employed to model the behavior of the cracked elements in the numerical simulations. The results indicate that the HHT method can reasonably identify the damage locations based on a limited number of acceleration sensors. Experimental study has been 실so carried out on a steel frame to confirm the applicability of the HHT to detect a structural connection with loosened bolts.

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Modeling of Blend Surfaces by Bezier Surface Patches (비지어곡면에 의한 블렌드곡면의 모델링)

  • 주상윤
    • Korean Journal of Computational Design and Engineering
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    • v.2 no.2
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    • pp.122-129
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    • 1997
  • Ball rolling blending is a popular technique for blending between parametric surfaces. The ball rolling blend surface is conceptually a trajectory of a ball rolling between two base sufaces. It is constructed by sweeping a circular arc along a ball contact curve pair. Since a ball rolling blend surfaces does not have a polynomial form like a Bezier surface patch, it is impossible to apply this method directly to a commercial CAD/CAM system. In this paper an algorithm is developed to approximate a ball rolling blend surface into Bezier surface patches. Least square method is applied to obtain proper Bezier surface patches under a given tolerance. The Bezier surface patches have degree three or more and guarantee VC1-continuity.

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Pipe Offset Routing Program By Using 3D CAD For Shipbuilding (조선전용 3차원 CAD 시스템을 이용한 Pipe Offset Routing 프로그램 개발)

  • Kim, Sung-Min;Sheen, Dong-Mok
    • Journal of the Society of Naval Architects of Korea
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    • v.45 no.4
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    • pp.432-440
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    • 2008
  • Korean shipbuilders are starting to use three dimensional solid CAD systems to enhance their competitiveness in design and production. Despite many merits, three dimensional CAD systems reveal some problems in pipe-line modeling. Pipe-line modeling is heavily dependent on point data in routing. However, since the models built by sweeping or skinning operations do not have data about points and lines on the surfaces, the point data for routing are currently manually calculated by considering the diameters of the pipes and alignment conditions with other pipes. This process is inefficient and prone to errors. In order to enhance the pipe modeling, this paper presents an Offset Routing Program for a three dimensional CAD system, which aids designers to easily define the start points and to generate the pipe routings using reference objects.

Applicable Road Design Method of Debris-Flow Control Structure (토석류 차단시설의 도로적용 설계 방안)

  • Lee, Yong-Soo;Kim, Jin-Hwan;Yu, Jun;Chung, Ha-Ik
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.243-246
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    • 2009
  • Localized rainfall due to abnormal climate has caused extensive damages killing several tens to hundreds of people for yearly basis. The typhoon 'Lusa' of year 2002 has resulted 5,400 billion won of property damage and the damages for roads were approximated to be 2,860 billion won at 12,377 locations holding 53% damage of total. The recent typhoon, 'Aewinia' of yeat 2006 caused the 1,400 billion-won property damage including sweeping and flooding of 127 roads and 65 rivers, respectively. There are needs to minimize the damages for important structures for repeated heavy rainfalls every year and, especially, because debris flow might be a main cause of road damage, the design criteria and guideline for roads are required to be improved. Therefore, this paper presented design method of debris-flow control structure for road protection.

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Drosophilid Survey of Mt. Sul-Ak (Kang-Won Province) (설악산의 초파리 분포조사)

  • 정용재;노분조
    • The Korean Journal of Zoology
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    • v.2 no.2
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    • pp.1-6
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    • 1959
  • 1. 저자들이 1959년 7월 14일부터 22일까지에 강원도 설악산의 9개소 즉 장수태, 십이탕골, 백담사, 오세암, 수강동, 봉정암, 가야동, 마등령, 및 신흥사에서 주로 복숭아 trap 법과 sweeping 법으로 채집한 Drosophilidae 는 4 촉 4 아촉 22종 512 개체였다. 2. D.auraria, D. testacea, D.brachynephros, D.sexivitata, D.unispina, D.bifasciata, Amiota variegata, D.angularis 및 D. histrio가 다수 채집되었으며 Mycodrosophilachr과 Chymomyza 촉의 종은 본 채집에서 볼 수 없었고 다른곳에서 흔히 잡히는 D.bizohnata D.bizonnata, D.nigrmaculata 도 채집되어지지 않았다. 3. D.sexivittata, D.testacea 의 Polymorphism, D.brachynephros, D. angularis,D. unispina의 구별, D. lacertosa 와 Amiota variegata 의 crossvein, A. alboguttata 의 genitalia , D, histrio의 abominal band 및 crossvein , A. alboguttata 의 genitalia, D.histrio의 abominal band 및 crossvein $C_3$ bristle 문제를 검토했다. 4. D.kuntzeisms 한국산 Drosophilidae 목록에 새로 첨가할 미기록종이며 미지종 3 종 즉 A(A.) sp., d.(D.) sp., D.(S.) sp like helvetica BURLA 의 검토를 예의 진행중에 있다.

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Reinforcement Learning Using State Space Compression (상태 공간 압축을 이용한 강화학습)

  • Kim, Byeong-Cheon;Yun, Byeong-Ju
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.3
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    • pp.633-640
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    • 1999
  • Reinforcement learning performs learning through interacting with trial-and-error in dynamic environment. Therefore, in dynamic environment, reinforcement learning method like Q-learning and TD(Temporal Difference)-learning are faster in learning than the conventional stochastic learning method. However, because many of the proposed reinforcement learning algorithms are given the reinforcement value only when the learning agent has reached its goal state, most of the reinforcement algorithms converge to the optimal solution too slowly. In this paper, we present COMREL(COMpressed REinforcement Learning) algorithm for finding the shortest path fast in a maze environment, select the candidate states that can guide the shortest path in compressed maze environment, and learn only the candidate states to find the shortest path. After comparing COMREL algorithm with the already existing Q-learning and Priortized Sweeping algorithm, we could see that the learning time shortened very much.

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Design of a Spatial Hash Strip Join Algorithm using Efficient Bucket Partitioning and Joining Methods (효율적인 버킷 분할과 조인 방법을 이용한 공간 해쉬 스트립 조인 알고리즘 설계)

  • Shim, Young-Bok;Lee, Jong-Yun;Jung, Soon-Key
    • Proceedings of the Korea Information Processing Society Conference
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    • 2003.11c
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    • pp.1367-1370
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    • 2003
  • 본 논문에서는 인덱스가 존재하지 않는 두 개의 입력 릴레이션에 대해서도 최적의 조인 연산을 수행할 수 있는 공간 해쉬 조인 알고리즘을 제안한다. 인덱스가 존재하지 않는 릴레이션의 처리에 사용하는 기존의 공간 해쉬 조인(SHJ: Spatial Hash Join)과 Scalable Sweeping-Rased Spatial Join(SSSJ) 알고리즘을 결합하여 SHJ 알고리즘의 단점으로 지적되고 있는 편향된(skewed) 데이터에 대한 조인 연산의 성능저하 문제를 개선한 수 있는 Spatial Hash Strip Join(SHSJ) 알고리즘을 제안한다. SHJ에서 편향된 데이터의 경우 해쉬 버킷의 오버플로우 처리를 위해 버킷 재분할 방법을 사용하고 있는데 반하여 본 논문에서 제안한 SHSJ 알괴리즘에서는 버킷의 재분할 처리 대신에 버킷에 데이터를 삽입하고, 조인 연산과정에서 오버플로우가 발생한 버킷에 대하여 SSSJ 알고리즘을 사용함으로써 편향된 입력 릴레이션의 처리 성능을 제고시킬 수 있도록 한다.

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Bonding Property of Silicon Wafer Pairs with Annealing Method (열처리 방법에 따른 실리콘 기판쌍의 접합 특성)

  • 민홍석;이상현;송오성;주영창
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.5
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    • pp.365-371
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    • 2003
  • We prepared silicon on insulator(SOI) wafer pairs of Si/1800${\AA}$ -SiO$_2$ ∥ 1800${\AA}$ -SiO$_2$/Si using water direct bonding method. Wafer pairs bonded at room-temperature were annealed by a normal furnace system or a fast linear annealing(FLA) equipment, and the micro-structure of bonding interfaces for each annealing method was investigated. Upper wafer of bonded pairs was polished to be 50 $\mu\textrm{m}$ by chemical mechanical polishing(CMP) process to confirm the real application. Defects and bonding area of bonded water pairs were observed by optical images. Electrical and mechanical properties were characterized by measuring leakage current for sweeping to 120 V, and by observing the change of wafer curvature with annealing process, respectively. FLA process was superior to normal furnace process in aspects of bonding area, I-V property, and stress generation.