• Title/Summary/Keyword: path dependence

Search Result 131, Processing Time 0.029 seconds

Comparison of Force Calculation Methods in 2D and 3D Finite Element Method

  • Yan Xiuke;Koh, Chang-Seop;Ryu, Jae-Seop;Xie Dexin
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
    • /
    • v.11B no.4
    • /
    • pp.137-145
    • /
    • 2001
  • The magnetic force calculation methods, the Maxwell's stress tensor method, virtual work method, and nodal force method, are reviewed and the equivalence of them are theoretically proved. The methods are applied to the magnetic force calculation of 2D linear and nonlinear problems, and 3D nonlinear problem. As the results, the convergence of the methods as the number of elements increases, accuracy of the methods, and integral path dependence of the methods are discussed. Finally some recommendations on the usage of the methods, including the determination of the integral path, are given.

  • PDF

Active Tonal Noise Control to Reduce the Low Frequency Tonal Sound (저주파 순음소음저감을 위한 능동 순음 소음제어)

  • 나희승;박영진
    • Journal of KSNVE
    • /
    • v.8 no.6
    • /
    • pp.1037-1042
    • /
    • 1998
  • This paper discusses the dependence of the convergence rate on the acoustic error path in these popular algorithms and introduces new algorithms which increase the convergence region regardless of the time-delay in the acoustic error path. We also Propose a novel control algorithm (AFC/CAFC) for tonal noise cancellation. The proposed algorithm estimates the magnitude and phase of the tonal noise. The algorithm uses the steepest descent method for the phase/magnitude estimation. Performances of tile CAFC algorithm are presented in comparison with those by the AFC algorithm based on computer simulations and experiments.

  • PDF

Active Noise Control Algorithm having Fast Convergence (빠른 수렴성을 갖는 능동 소음제어 알고리즘에 관한 연구)

  • 나희승;박영진
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 1998.04a
    • /
    • pp.670-677
    • /
    • 1998
  • Many of the adaptive noise control systems utilize a form of the least mean square (LMS) algorithm. In the active control of noise, it is common practice to locate an error microphone far from the control source to avoid the near-field effects by evanescent waves. Such a distance between the control source and the error microphone makes a certain level of time-delay inevitable and, hence, may yield undesirable effects on the convergence properties of control algorithms such as filtered-x LMS. This paper discusses the dependence of the convergence rate on the acoustic error path in these popular algorithms and introduces new algorithms which increase the convergence region regardless of the time-delay in the acoustic error path. Performances of the new LMS algorithms are presented in comparison with those by the conventional algorithms based on computer stimulations and experiments.

  • PDF

NHS: A Novel Hybrid Scheduling for ILP

  • You, Song-Pei;Mashiro Sowa
    • Proceedings of the IEEK Conference
    • /
    • 2000.07a
    • /
    • pp.310-313
    • /
    • 2000
  • This paper presents a new scheduling method for ILP processing called NHS(Novel Hybrid Scheduling). It concerns not only exploiting as much ILP as possible like other state-of-the-art scheduling scheme, but also choosing the most important instructions among many ready-to-execute instructions to processors in order to reduce the execution time under limited hardware resource. At the heart of NHS is a conception called CCP(Complex Critical Path), an extension of CP(Critical Path). By using CCP, compiler not only can get a global information of the whole program to extract ILP, but also can collecting data dependence information and control flow information. The paper also presents the simulation results, to date, of our attempts to study the NHS scheduling method. The results indicate good potential for this scheduling method.

  • PDF

Comparison of Force Calculation Methods in Finite Element Method (유한요소법을 이용한 전자기력 계산방법의 비교)

  • Xiuke, Yan;Ryu, Jae-Seop;Koh, Chang-Seop
    • Proceedings of the KIEE Conference
    • /
    • 2001.10a
    • /
    • pp.100-103
    • /
    • 2001
  • The magnetic force calculation methods, the Maxwell's stress tensor method, virtual work method, and nodal force method are reviewed. The methods are applied to the magnetic force calculation of 2D linear and nonlinear Problems. As the results the convergence of the methods as the number of elements increases, accuracy of the methods, and integral path dependence of the methods are discussed. Finally some recommendations on the usage of the methods, including the determination of the integral path, are given.

  • PDF

The Emotional Dimensions of North Korean Politics through the Lens of Historical Institutionalism

  • Kim, Hwajung
    • Journal of Contemporary Eastern Asia
    • /
    • v.21 no.2
    • /
    • pp.13-26
    • /
    • 2022
  • This study explores the following research question to address issues linked to emotions, identity, and institutions: how has the cult (institution) of the three Kims affected North Koreans' strong sense of nationalism (emotion), which is based on their Juche ideology (identity)? This paper investigates four fundamental elements of historical institutionalism: time boundedness, path dependency, institutional changes, and the shadow of the past. First, time boundedness illustrates how culture and education have been used to build trust and loyalty in the general public to construct individual and family cults. Second, path dependence reveals how the Songbun system has resulted in strong nationalism throughout Rodongdang's institutionalization. Third, institutional changes highlight the significance of age divides, as different age groups do not always support the three Kims' cult. Finally, the shadow of the past helps us understand the primary processes for generating mass ardent nationalism in the form of powerful impulses for self-sacrifice.

Effect of Path Loss Models for CDMA Base Station Deployment in LOS Environments (LOS 환경에서 CDMA 기지국 배치를 위한 Path Loss Model의 영향)

  • Min, Seung-Wook
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.36 no.1A
    • /
    • pp.1-7
    • /
    • 2011
  • Cell Capacity and cell layout are strongly dependent on the up-link interference caused by out-of-cell mobiles. Accurate prediction of the propagation path loss from out-of-cell mobiles is essential to achieve system designs that minimize the infrastructure required for a given quality of service (QOS). Less accurate predictions can be expected to yield designs requiring the use of a greater number of base stations. In order to quantify the dependence of infrastructure on prediction accuracy, this paper considers the cellular systems, LOS (line of sight) cells along a road or highway.

Near-ground boundary layer wind characteristics analysis of Typhoon "Bailu" based on field measurements

  • Dandan Xia;Li Lin;Liming Dai;Xiaobo Lin
    • Wind and Structures
    • /
    • v.39 no.1
    • /
    • pp.15-30
    • /
    • 2024
  • In this paper, detailed wind field data of the full path of typhoon "Bailu" were obtained based on site measurements. Typhoon "Bailu" made first landfall southeast of the Taiwan Strait with a wind speed of approximately 30 m/s near the center of the typhoon eye and a second landfall in Dongshang County in Fujian Province. The moving process is classified into 3 regions for analysis and comparison. Detailed analyses of wind characteristics including wind profile, turbulence intensity, gust factor, turbulence integral scale and wind power spectral density function at the full process of the typhoon are conducted, and the findings are presented in this paper. Wind speed shows significant dependence on both the direction of the moving path and the distance between the typhoon center and measurement site. Wind characteristics significantly vary with the moving path of the typhoon center. The relationship between turbulence intensity and gust factor at different regions is investigated. The integral turbulence scales and wind speed are fitted by a Gaussian model. Such analysis and conclusions may provide guidance for future bridge wind-resistant design in engineering applications.

Tier-based Proactive Path Selection Mode for Wireless Mesh Networks

  • Fu-Quan, Zhang;Joe, In-Whee;Park, Yong-Jin
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.6 no.5
    • /
    • pp.1303-1315
    • /
    • 2012
  • In the draft of the IEEE 802.11s standard, a tree topology is established by the proactive tree-building mode of the Hybrid Wireless Mesh Protocol (HWMP). It is used for cases in which the root station (e.g., gateway) is an end point of the majority of the data connections. In the tree topology, the root or central stations (e.g., parent stations) are connected to the other stations (e.g., leaves) that are one level lower than the central station. Such mesh stations are likely to suffer heavily from contention in bottleneck links when the network has a high traffic load. Moreover, the dependence of the network on such stations is a point of vulnerability. A failure of the central station (e.g., a crash or simply going into sleep mode to save energy) can cripple the whole network in the tree topology. This causes performance degradation for end-to-end transmissions. In a connected mesh topology where the stations having two or more radio links between them are connected in such a way that if a failure subsists in any of the links, the other link could provide the redundancy to the network. We propose a scheme to utilize this characteristic by organizing the network into concentric tiers around the root mesh station. The tier structure facilitates path recovery and congestion control. The resulting mode is referred to as Tier-based Proactive Path Selection Mode (TPPSM). The performance of TPPSM is compared with the proactive tree mode of HWMP. Simulation results show that TPPSM has better performance.

Study on the Change of Nuclear Energy Policy: Before and After Fukushima Nuclear Accident (원자력 정책 변동에 관한 연구: 후쿠시마 원전 사고 전후를 중심으로)

  • Park, Soo-Kyung;Jang, Dong-Hyun
    • The Journal of the Korea Contents Association
    • /
    • v.19 no.6
    • /
    • pp.222-235
    • /
    • 2019
  • Since Fukushima nuclear disaster occurred in 2011, the nuclear energy policy of the international society has been in recession. However, In Korea, the nuclear-friendly policy had remained and even expanded over the last 60 years until the Park Geun-hye government. In other words, there was the path dependence of nuclear energy policy. Since the Moon Jae-in government that pledged to perform nuclear phase-out policy in 2017 was inaugurated, the nuclear-friendly policy began to swerve from the course of path dependence. Based on the mai logic of historical institutionalism, this study looked into the change of Korean nuclear policy by before and after the Fukushima nuclear accident. As the result of this research, the external situation of Fukushima Nuclear Accident became a critical turning point and led to a change in the government's policy on nuclear power. From an institutional perspective, it influenced the paradigm of nuclear power policy, policy decision structure, and laws of nuclear power. From a doer's perspective, it influenced political idea and social acceptability. Since Moon Jae-in government was inaugurated in 2017, nuclear phase-out policy has secured its institutional foundation and nuclear power policy has basically changed from nuclear-friendly policy to nuclear phase-out policy. Therefore, the energy policy of Moon Jae-in government gets out of the nuclear power based path dependency that previous governments pursued, keeps punctuated equilibrium, and changes to renewable energy oriented policy.