• Title/Summary/Keyword: local approaches

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A Forwarding Scheme for (m,k)-firm Streams Based on Local Decision in Wireless Sensor Networks

  • Li, Bijun;Kim, Ki-Il
    • Journal of information and communication convergence engineering
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    • v.9 no.6
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    • pp.775-779
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    • 2011
  • As the technology of multimedia sensor networks is desired in large numbers of applications nowadays, real-time service becomes one of the most important research challenges. Even though lots of related works have been conducted to meet this requirement in several ways, the specific traffic model for real-time has not been taken yet. Thus, it causes lack of adaptability of those approaches in real deployment. To solve this problem, in this paper, we model the application via (m,k)-firm streams which have weakly hard real-time property. And then, a novel forwarding scheme based on modified DBP (Distance-Based Priority) is proposed by considering local-DBP and stream DBP together. Local-DBP can contribute to identify the detailed causes of unsatisfied quality, that is, network congestion or wireless link failure. Simulation results reveal that (m,k)-firm is a good traffic model for multimedia sensor networks and the proposed scheme can contribute to guarantee real-time requirement well.

Evaluation of Ductile Fracture Characteristics Based on Local Approach (국부접근법에 입각한 연성재료의 파괴특성 평가)

  • Lee, Tae-Rin;Chang, Yoon-Suk;Choi, Jae-Boong;Kim, Young-Jin
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.49-54
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    • 2004
  • Several cell models, so-called local approach, have been proposed as engineering approaches to numerically simulate ductile fracture characteristics. In this paper, two- and three-dimensional finite element analyses incorporating both modified GTN and Rousselier models were carried out. Smooth and notched bars and CT25 specimens were assessed for StE460 and DIN22NiMoCr37 materials which were quoted from previous researches. Micro-mechanical parameters used in the assessment were established by fitting the numerical results with the experiments, and J-R curves derived from the simulations were found to be in good agreement with the corresponding experimental results.

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Haptic Simulation with s-FEM (s-FEM 을 이용한 햅틱 시뮬레이션)

  • Jun, Seong-Ki;Cho, Maeng-Hyo
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.780-785
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    • 2007
  • Accurate and fast haptic simulations of deformable objects are desired in many applications such as medical virtual reality. In haptic interactions with a coarse model, the number of nodes near the haptic interaction region is too few to generate detailed deformation. Thus, local refinement techniques need to be developed. Many approaches have employed purely geometric subdivision schemes, but they are not proper in describing the deformation behavior of deformable objects. This paper presents a continuum mechanics-based finite element adaptive method to perform haptic interaction with a deformable object. This method superimposes a local fine mesh upon a global coarse model, which consists of the entire deformable object. The local mesh and the global mesh are coupled by the s-version finite element method (s-FEM), which is generally used to enhance accurate solutions near the target points even more. The s-FEM can demonstrate a reliable deformation to users in real-time.

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MINIMAL LOCALLY STABILIZED Q1-Q0 SCHEMES FOR THE GENERALIZED STOKES PROBLEM

  • Chibani, Alima;Kechkar, Nasserdine
    • Journal of the Korean Mathematical Society
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    • v.57 no.5
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    • pp.1239-1266
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    • 2020
  • In this paper, some novel discrete formulations for stabilizing the mixed finite element method Q1-Q0 (bilinear velocity and constant pressure approximations) are introduced and discussed for the generalized Stokes problem. These are based on stabilizing discontinuous pressure approximations via local jump operators. The developing idea consists in a reduction of terms in the local jump formulation, introduced earlier, in such a way that stability and convergence properties are preserved. The computer implementation aspects and numerical evaluation of these stabilized discrete formulations are also considered. For illustrating the numerical performance of the proposed approaches and comparing the three versions of the local jump methods alongside with the global jump setting, some obtained results for two test generalized Stokes problems are presented. Numerical tests confirm the stability and accuracy characteristics of the resulting approximations.

Intelligent Control of Induction Motor Using Hybrid System GA-PSO

  • Kim, Dong-Hwa;Park, Jin-Il
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1086-1091
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    • 2005
  • This paper focuses on intelligent control of induction motor by hybrid system consisting of GA-PSO. Induction motor has been using in industrial area. However, it is challengeable on how we control effectively. From this point, an optimal solution using GA (Genetic Algorithm) and PSO (Particle Swarm Optimization) is introduced to intelligent control. In this case, it is possible to obtain local solution because chromosomes or individuals which have only a close affinity can convergent. To improve an optimal learning solution of control, This paper deal with applying PSO and Euclidian data distance to mutation procedure on GA's differentiation. Through this approaches, we can have global and local optimal solution together, and the faster and the exact optimal solution without any local solution. Four test functions are used for proof of this suggested algorithm.

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Study for Local Glass Transition of Bulk Metallic Glasses using Atomic Strain (원자변형률을 이용한 비정질 금속의 천이온도에 관한 연구)

  • Park, Jun-Young
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.5
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    • pp.104-109
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    • 2011
  • Bulk metallic glasses (BMG) have been greatly improved by the advance of synthesis process during last three decades. It was also found that the Glass Forming Ability (GFA) strongly depends on the glass transition temperature. When the temperature approaches to a critical value, the crystals nucleation from the supercooled liquid can be suppressed so that bulk glass formation possible. Egami and others found that the local glass transition temperature depends on the volumetric strain of each atom and suggested the critical transition temperature. In this paper, we explore the strain dependency of local glass transition temperature using the atomic strain defined by the deformation tensor for the Voronoi polyhedra.

Haptic Simulation for Deformable Object with s-FEM (s-FEM을 이용한 변형체 햅틱 시뮬레이션)

  • Jun Seong-Ki;Choi Jin-Bok;Cho Maeng-Hyo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2006.04a
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    • pp.373-380
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    • 2006
  • Accurate and fast haptic simulations of deformable objects are desired in many applications such as medical virtual reality. In haptic interactions with a coarse model, the number of nodes near the haptic interaction region is too few to generate detailed deformation. Thus, local refinement techniques need to be developed. Many approaches have employed purely geometric subdivision schemes, but they are not proper in describing the deformation behavior of deformable objects. This paper presents a continuum mechanics-based finite element adaptive method to perform haptic interaction 'with a deformable object. This method superimposes a local fine mesh upon a global coarse model, which consists of the entire deformable object. The local mesh and the global mesh are coupled by the s-version finite element method (s-FEM), which is generally used to enhance accurate solutions near the target points even more. The s-FEM can demonstrate a reliable deformation to users in real-time.

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Competency Development in Urban Local Bodies for Implementing Public Private Partnership Projects in India

  • Devkar, Ganesh A.;Kalidindi, Satyanarayana N.
    • Journal of Construction Engineering and Project Management
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    • v.3 no.2
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    • pp.35-48
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    • 2013
  • Weak competencies in urban local bodies (ULBs) for implementing public private partnership (PPP) projects has been recognized as a major hurdle in uptake of PPP model in India. In this context, a questionnaire survey was conducted to evaluate perception of urban PPP experts and ULB representatives on three aspects related to competency development, including, critical competencies for implementing urban PPP projects, approaches for competency development in ULBs and constraints faced by ULBs in development of competencies. The five critical competencies identified are project identification, project conceptualization, transaction design, PPP process management and contract management. The approach of training programs for municipal staff and elected representatives, and capacity building oriented technical assistance for implementing urban PPP projects have been preferred by survey respondents for competency development. The frequent transfer of municipal decision makers and low motivation among municipal staff have been identified as the most significant constraints for development of competencies.

Detection of local structural chages in time series (시계열에서 국소구조변화의 탐지에 관한 연구)

  • Jae June Lee
    • The Korean Journal of Applied Statistics
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    • v.7 no.2
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    • pp.299-311
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    • 1994
  • In time series data, atypical observations are not rare. Several approaches have been proposed to detect a single outlier, but the effectiveness of those procedures is in doubt when patchy outliers are present. In this paper, the atypicality in patchy outliers is interpreted as a local structural change, and a model is introduced to entertain its effect on the series. Based on this model, a statistic and a procedure are proposed for identifying those local structural changes. The performance of the proposed procedure is evaluated through simulation study and the analysis of real data sets.

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Metaphor and Cognitive Map: Analysis on the image of local government (메타포(metaphor)와 인지지도 분석: 지방정부에 대한 이미지를 중심으로)

  • Kim, Dong-Hwan
    • Korean System Dynamics Review
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    • v.12 no.3
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    • pp.5-23
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    • 2011
  • Studies in social science are performed on the language of social actors. While a metaphor analysis focuses on the meaning of the language, a cognitive map analysis deals with its external relationships. If we can put together both analyses, it will be possible to investigate the internal meanings and external relationship of the language and image at the same time. In this paper, metaphor analysis and cognitive map approach is applied to find the image of local governments. This study shows how to link metaphor analysis to the cognitive map and the benefit of using both approaches together.

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