• 제목/요약/키워드: global frame

검색결과 406건 처리시간 0.023초

Discriminative Training of Sequence Taggers via Local Feature Matching

  • Kim, Minyoung
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • 제14권3호
    • /
    • pp.209-215
    • /
    • 2014
  • Sequence tagging is the task of predicting frame-wise labels for a given input sequence and has important applications to diverse domains. Conventional methods such as maximum likelihood (ML) learning matches global features in empirical and model distributions, rather than local features, which directly translates into frame-wise prediction errors. Recent probabilistic sequence models such as conditional random fields (CRFs) have achieved great success in a variety of situations. In this paper, we introduce a novel discriminative CRF learning algorithm to minimize local feature mismatches. Unlike overall data fitting originating from global feature matching in ML learning, our approach reduces the total error over all frames in a sequence. We also provide an efficient gradient-based learning method via gradient forward-backward recursion, which requires the same computational complexity as ML learning. For several real-world sequence tagging problems, we empirically demonstrate that the proposed learning algorithm achieves significantly more accurate prediction performance than standard estimators.

마그네틱 콤파스 기반의 전 방향 로봇의 방위각 제어 (Azimuth Tracking Control of an Omni-Directional Mobile Robot(ODMR) Using a Magnetic Compass)

  • 이정형;정슬
    • 제어로봇시스템학회논문지
    • /
    • 제15권2호
    • /
    • pp.132-138
    • /
    • 2009
  • In this paper, control of an omni-directional mobile robot is presented. Relying on encoder measurements to define the azimuth angle yields the dead-reckoned situation which the robot fails in localization. The azimuth angle error due to dead-reckoning is compensated and corrected by the magnetic compass sensor. Noise from the magnetic compass sensor has been filtered out. Kinematics and dynamics of the omni-directional mobile robot are derived based on the global coordinates and used for simulation studies. Experimental studies are also conducted to show the correction by the magnetic compass sensor.

철근 콘크리트 특수 모멘트 골조 건물의 비탄성 동적 성능값 (Nonlinear Dynamic Capacity of Reinforced Concrete Special Moment Frame Buildings)

  • 김태완;김태진
    • 한국지진공학회:학술대회논문집
    • /
    • 한국지진공학회 2006년도 학술발표회 논문집
    • /
    • pp.209-216
    • /
    • 2006
  • For evaluation of building performance, a nonlinear dynamic capacity of the building is a key parameter. In this study, an reinforced concrete special moment resisting frame building was chosen to study the process of determining the nonlinear dynamic capacity. The building, which was designed by IBC 2003 representing new codes, was composed of special moment resisting frames in the perimeter and internal frames inside the building. The capacity, which is inter-story drift capacity, consists of two categories, local and global collapses. Global collapse capacity was determined by incremental dynamic analysis. Local collapse capacity was determined by the same method except for utilizing damage index. In audition to this, it was also investigated that the effect of including internal frames designed by gravity load in the analysis. Results showed that the damage index is a useful tool for determining local collapse. Furthermore, including the internal frames with special frames in the analysis is very important in determining the capacity of a building so both must be considered at the same time.

  • PDF

Full-length ORF2 sequence-based genetic and phylogenetic characterization of Korean feline caliciviruses

  • Kim, Sung Jae;Kim, Cheongung;Chung, Hee Chun;Park, Yong Ho;Park, Kun Taek
    • Journal of Veterinary Science
    • /
    • 제22권3호
    • /
    • pp.32.1-32.8
    • /
    • 2021
  • Feline calicivirus (FCV) is a highly infectious pathogen in cats and widely distributed worldwide with high genetic variation. Full-length open reading frame 2 of 5 from recently isolated Korean FCV isolates were sequenced and compared with those of global isolates. The results of phylogenetic analysis supported dividing global FCV isolates into two genogroups (type I and II) and demonstrated the presence of genogroup II in Korea, indicating their geographic spread in East Asia. High sequence variations in region E of the FCV isolates emphasizes that a novel vaccine needs to be developed to induce protective immunity against various FCV strains.

메움벽에 의한 R/C 골조의 내진성능 평가에 관한 연구 (Experimental Study of Infilled Wall in Reinforced Concrete Structure)

  • 김석균;김정한;김영문
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
    • /
    • pp.403-406
    • /
    • 1999
  • Although infilled wall considered as a non-structural element, the infilled applied in reinforced concrete frame structural systems represents an important element influencing the behaviour and the stability of a structure under seismic effect. This research is performed an experimental investigation of gravity-load designed single-stroy, single-bay, low-rise nonseismic moment-resisting reinforced concrete frame 2 dimension specimens to evaluate the effect of seismic capacity. For pseudo static test, it was manufactured one half scale specimens of two types (Bare Frame, Infilled Frame) based on typical building. The results of these experiments provided regarding the global as well as the local responses of 1) Crack pattern and failure modes, 2) Stiffness, strength.

  • PDF

A Coupled Finite Element Analysis of Independently Modeled Substructures by Penalty Frame Method

  • Maenghyo Cho;Kim, Won-Bae
    • Journal of Mechanical Science and Technology
    • /
    • 제16권10호
    • /
    • pp.1201-1210
    • /
    • 2002
  • A penalty frame method is proposed for the coupled analysis of finite elements with independently modeled substructures. Although previously reported hybrid interface method by Aminpour et al (IJNME, Vol 38, 1995) is accurate and reliable, it requires non-conventional special solution algorithm such as multifrontal solver. In present study, an alternative method has been developed using penalty frame constraints, which results in positive symmetric global stiffness matrices. Thus the conventional skyline solver or band solver can be utilized in the solution routine, which makes the present method applicable in the environment of conventional finite element commercial software. Numerical examples show applicability of the present method.

A hybrid imperialist competitive ant colony algorithm for optimum geometry design of frame structures

  • Sheikhi, Mojtaba;Ghoddosian, Ali
    • Structural Engineering and Mechanics
    • /
    • 제46권3호
    • /
    • pp.403-416
    • /
    • 2013
  • This paper describes new optimization strategy that offers significant improvements in performance over existing methods for geometry design of frame structures. In this study, an imperialist competitive algorithm (ICA) and ant colony optimization (ACO) are combined to reach to an efficient algorithm, called Imperialist Competitive Ant Colony Optimization (ICACO). The ICACO applies the ICA for global optimization and the ACO for local search. The results of optimal geometry for three benchmark examples of frame structures, demonstrate the effectiveness and robustness of the new method presented in this work. The results indicate that the new technique has a powerful search strategies due to the modifications made in search module of ICACO. Higher rate of convergence is the superiority of the presented algorithm in comparison with the conventional mathematical methods and non hybrid heuristic methods such as ICA and particle swarm optimization (PSO).

Real-Time Digital Image Stabilization for Cell Phone Cameras in Low-Light Environments without Frame Memory

  • Luo, Lin-Bo;Chong, Jong-Wha
    • ETRI Journal
    • /
    • 제34권1호
    • /
    • pp.138-141
    • /
    • 2012
  • This letter proposes a real-time digital image stabilization system for cell phone cameras without the need for frame memory. The system post-processes an image captured with a safe shutter speed using an adaptive denoising filter and a global color correction algorithm. This system can transfer the normal brightness of an image previewed under long exposure to the captured image making it bright and crisp with low noise. It is even possible to take photos in low-light conditions. By not needing frame memory, the approach is feasible for integration into the size-constrained image sensors of cell phone cameras.

Structural behavior of conventional and buckling restrained braced frames subjected to near-field ground motions

  • Guneyisi, Esra Mete;Ameen, Nali
    • Earthquakes and Structures
    • /
    • 제7권4호
    • /
    • pp.553-570
    • /
    • 2014
  • In this study, nonlinear dynamic analyses were performed in order to evaluate and compare the structural response of different type of moment resisting frame buildings equipped with conventional braces (CBs) and buckling restrained braces (BRBs) subjected to near-field ground motions. For this, the case study frames, namely, ordinary moment-resisting frame (OMRF) and special moment-resisting frame (SMRF) having two equal bays of 6 m and a total height of 20 m were utilized. Then, CBs and BRBs were inserted in the bays of the existing frames. As a brace pattern, diagonal type with different configurations were used for the braced frame structures. For the earthquake excitation, artificial pulses equivalent to Northridge and Kobe earthquake records were taken into account. The results in terms of the inter-story drift index, global damage index, base shear, top shear, damage index, and plastification were discussed. The analysis of the results indicated a considerable improvement in the structural performance of the existing frames with the inclusion of conventional and especially buckling-restrained braces.

Seismic performance evaluation of a RC special moment frame

  • Kim, Taewan;Kim, Jinkoo
    • Structural Engineering and Mechanics
    • /
    • 제27권6호
    • /
    • pp.671-682
    • /
    • 2007
  • The probability and the reliability-based seismic performance evaluation procedure proposed in the FEMA-355F was applied to a reinforced concrete moment frame building in this study. For the FEMA procedure, which was originally developed for steel moment frame structures, to be applied to other structural systems, the capacity should be re-defined and the factors reflecting the uncertainties related to capacity and demand need to be determined. To perform the evaluation procedure a prototype building was designed per IBC 2003, and inelastic dynamic analyses were conducted applying site-specific ground motions to determine the parameters for performance evaluation. According to the analysis results, distribution of the determined capacities turned out to be relatively smaller than that of the demands, which showed that the defined capacity was reasonable. It was also shown that the prototype building satisfied the target performance since the determined confidence levels exceeded the objectives for both local and global collapses.