• 제목/요약/키워드: Distributed model

검색결과 4,089건 처리시간 0.029초

Fiber element-based nonlinear analysis of concrete bridge piers with consideration of permanent displacement

  • Ansari, Mokhtar;Daneshjoo, Farhad;Safiey, Amir;Hamzehkolaei, Naser Safaeian;Sorkhou, Maryam
    • Structural Engineering and Mechanics
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    • 제69권3호
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    • pp.243-255
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    • 2019
  • Utilization of fiber beam-column element has gained considerable attention in recent years due mainly to its ability to model distributed plasticity over the length of the element through a number of integration points. However, the relatively high sensitivity of the method to modeling parameters as well as material behavior models can pose a significant challenge. Residual drift is one of the seismic demands which is highly sensitive to modeling parameters and material behavior models. Permanent deformations play a prominent role in the post-earthquake evaluation of serviceability of bridges affected by a near-fault ground shaking. In this research, the influence of distributed plasticity modeling parameters using both force-based and displacement-based fiber elements in the prediction of internal forces obtained from the nonlinear static analysis is studied. Having chosen suitable type and size of elements and number of integration points, the authors take the next step by investigating the influence of material behavioral model employed for the prediction of permanent deformations in the nonlinear dynamic analysis. The result shows that the choice of element type and size, number of integration points, modification of cyclic concrete behavior model and reloading strain of concrete significantly influence the fidelity of fiber element method for the prediction of permanent deformations.

A cross-domain access control mechanism based on model migration and semantic reasoning

  • Ming Tan;Aodi Liu;Xiaohan Wang;Siyuan Shang;Na Wang;Xuehui Du
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제18권6호
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    • pp.1599-1618
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    • 2024
  • Access control has always been one of the effective methods to protect data security. However, in new computing environments such as big data, data resources have the characteristics of distributed cross-domain sharing, massive and dynamic. Traditional access control mechanisms are difficult to meet the security needs. This paper proposes CACM-MMSR to solve distributed cross-domain access control problem for massive resources. The method uses blockchain and smart contracts as a link between different security domains. A permission decision model migration method based on access control logs is designed. It can realize the migration of historical policy to solve the problems of access control heterogeneity among different security domains and the updating of the old and new policies in the same security domain. Meanwhile, a semantic reasoning-based permission decision method for unstructured text data is designed. It can achieve a flexible permission decision by similarity thresholding. Experimental results show that the proposed method can reduce the decision time cost of distributed access control to less than 28.7% of a single node. The permission decision model migration method has a high decision accuracy of 97.4%. The semantic reasoning-based permission decision method is optimal to other reference methods in vectorization and index time cost.

Spatial analysis of soil erosion and deposition using physics-based distributed model

  • Min Geun Song;Young Hun Kim;Chan Ul Choi;Van Linh Nguyen;Min Ho Yeon
    • 농업과학연구
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    • 제51권3호
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    • pp.375-389
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    • 2024
  • Soil erosion, a critical environmental issue primarily driven by water and wind, has severe consequences, including the loss of fertile agricultural land, degradation of water quality, and sediment accumulation in riverbeds. This study utilized the SSEM (surface soil erosion model), a physically-based distributed model, to simulate the rainfall-runoff-sediment dynamics associated with short-term rainfall events in the Naerin River basin. A spatial analysis of erosion and deposition was conducted, taking into account topographical factors such as local slope and overland flow length. The study area was segmented into six sub-catchments using Strahler's stream order method to examine the correlation between geographic factors and erosion or deposition. The findings revealed that erosion was predominant within flow path distances of 0 - 1 km (adjacent to the river) and 3 - 4 km (in the upper catchment areas). Notably, deposition did not occur in areas beyond 2.5 km from the river. Furthermore, it was observed that average erosion depth increased on steeper slopes (exceeding 0.3 - 0.4 degrees), whereas deposition was absent in these steep slope classes.

개발 생산성 향상을 위한 분산 시스템 기반의 프레임워크 설계 (A Design of Framework based on Distributed System for Enhancing Productivity)

  • 최병하;최승교;조경산
    • 한국컴퓨터정보학회논문지
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    • 제17권1호
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    • pp.53-60
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    • 2012
  • 본 논문은 분산 시스템 기반에서 경량급 프레임워크의 간단한 개발 주기를 지원하며 분산 처리가 가능한 IPO(Input-Process-Output) 모델 기반의 프레임워크를 제안한다. 제안 프레임워크는 입력 함수, 처리 함수, 출력 함수를 가진 클래스를 개발하면 분산 시스템의 표현 계층과 중간 계층에서 하나의 응용 프로그램으로 실행되도록 지원해준다. 또한 이 기법의 특징으로 응용 프로그램 개발시 분산 시스템 의존적인 부분을 제거하며, 개발-구축-배치-검증의 개발 주기를 개발-검증 주기로 감소시킨다. 이 기법의 생산성 향상과 성능 검증하기 위해 기존의 분산 시스템과 경량급 프레임워크의 응용 프로그램을 제안 기법의 응용 프로그램과 비교 분석한다. 그 결과 상당한 코드 감소와 분산 시스템 의존적인 부분이 감소하여 개발 생산성을 향상시키고 경량급 시스템에 비해 상대적으로 안전적인 성능을 보인다.

GIS와 불확실도 해석기법을 이용한 분포형 강우 - 유출 모형의 개발 (I) - 이론 및 모형의 개발 - (Development of Distributed Rainfall-Runoff Model by Using GIS and Uncertainty Analysis (I) - Theory and Development of Model -)

  • 최현상;한건연
    • 한국수자원학회논문집
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    • 제37권4호
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    • pp.329-339
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    • 2004
  • 본 연구의 목적은 유역에서의 강우-유출 과정 모의를 위해 GIS에 기반을 둔 2차원 강우-유출 해석모형의 개발이다. 본 연구가 추구하는 세부 목표는 첫째, 강우--유출해석을 위한 2차원 모형을 개발하고, 둘째, 개발된 모형과 GIS를 연계하는 것이다. 모형에 포함된 수식화 과정은 다음의 네 가지로 요약학 수 있다. 시$\cdot$공간적으로 분포하는 강우의 처리과정과 침투과성, 유역의 유출을 추적하기 위한 1, 4, 8방향 흐름 추적과정, 그리고 하도 추적을 위한 1차원 해석과정이다. 개발된 모형에 Monte Carlo 모의기법을 결합하여 추계학적 모형을 구성하였다. 모형에 필요한 입력자료(고도, 토양도, 강우자료 등)의 구축과 모의결과의 도시를 위해 Arc/Info와 ArcView를 연계ㆍ활용한 시스템을 구성하였다.

System Dynamics법을 이용한 동북아항만 경쟁모델에 관한 연구 (On the Competitive Model among Northeast Asia Port by System Dynamics Method)

  • 여기태;이철영
    • 한국항만학회지
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    • 제12권1호
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    • pp.1-8
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    • 1998
  • If a system has a large boundary and complexity, forecast's accuracy will be very low when consider the system's substance as black box. Thus, it is necessary that analysis by structure model. To examine competition in Northeast Asia Ports, it has assumed that the form of structure model, For which the System Dynamics method is adapted in this paper. Northeast Asia Ports Model includes five ports - Pusan, Kobe, Yokohama, Kaoshiung, Keelung, - which are adjacent to each other by geographically and has a competition relation. The Northeast Asia Ports Model has several sub-systems which consists of each unit port models. And, each unit port model found by quantitive, qualititive factors and their feedback loops. All effects which components of one port have influence to components of the rest ports must be surveyed in order to construct Northeast Asia Ports Model, but it may be impossible currently. In this paper Northeast Asia Ports Model was simplified by HFP-Hierarchical Fuzzy Process Method-adapted to integration of level variables of unit port model. Container cargo volumes in Northeast Ports Model is distributed by results of HFP method. And distributed container cargo volumes effected to unit port model. Developed model can estimate change of container cargo volumes in competitive relation by alternation of simple parameter, and reflects dynamics characteristics which are included in model.

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조기경보 체제를 위한 통합 레이다 정보처리 시스템의 설계 및 성능분석에 관한 연구 (A study on the Design and the Performance Analysis of Radar Data Integrating Systems for a Early Warning System)

  • 이상웅;라극환;조동래
    • 전자공학회논문지A
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    • 제29A권11호
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    • pp.25-39
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    • 1992
  • Due to the data processing development by the computer, the early warning system recently has made a remarkable evolution in its functions and performance as a component of the communication and control system which is also supported by the computer communication and intelligence system. In this paper it is presented that a integrated data processing system is designed to integrate the information sent from the various radar systems which constitute an early warning system. The suggested system model of this paper is devided into two types of structures, the centralized model and the distributed model, according to the data processing algorithm. We apply the queueing theory to analyse the performance of the designed models and the OPNET system kernel to make the analysing program with C language. From the analysis of the queueing components by applying the analysis programs to the designed systems, we got the tendancies and characteristics of both models, that is, a fast data processing performance of the distributed model and a stable data processing capability of the centralized model.

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Performance Analysis of Distribution-based and Replication-based Model for High Performance Grid Information Service

  • Quan, Cheng-Hao;Kim, Hie-Cheol;Lee, Kang-Woo;Lee, Yong-Doo
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅲ
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    • pp.1621-1624
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    • 2003
  • As the entities participating Grid become larger, performance requirement for the LDAP-based GIS(Grid Information Service) goes beyond that provided by a stand-alone single LDAP server. This entails the exploration of distributed LDAP systems. This paper presents the performance evaluation respectively for a distribution-based and a replication-based LDAP model. The analysis is based on an analytic performance model for each distributed system which is obtained by applying the M/M/1 queuing model. The performance evaluation made to these analytic models reveals that the distribution-based and the replication-based model show a significant tradeoff in their performance with respect to the system size as well as the amount of system load.

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체적부하를 갖는 유체 전달관로의 압력전파 특성 (The Propagation Characteristics of the Pressure in the Volume Loaded Fluid Transmission Line)

  • 윤선주;손병진
    • 대한기계학회논문집
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    • 제18권11호
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    • pp.3075-3083
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    • 1994
  • The applications of the electrical transmission line theory to the pressure propagation characteristics in the volume loaded fluid transmission line with step and impulse input wave is demonstrated in this paper. The method is based on the premise that the time response is the inverse Fourier transform of frequency spectrum of the wave which spectrum is a product of frequency spectrum of input pressure wave and system transfer function. The frequency response and transient response of step and impulse input wave in the volume loaded fluid transmission line is analysed by the Laplace transform and inverse Laplace transform with FFT numerical algorithm. The numerical solution of the distributed friction model is compared with the average friction model and the infinite product model. And the result is showed that FFT method may have major advantages for the simulation of fluid circuitary.

대용특성을 활용한 규준형 스크리닝 절차의 설계 (Design of Screening Procedures Using a Surrogate Variable with Specified Producer's and Consumer's Risks)

  • 홍성훈;정민영
    • 한국품질경영학회:학술대회논문집
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    • 한국품질경영학회 2009년도 추계학술대회
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    • pp.3-10
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    • 2009
  • When the measurement method for a performance variable is destructive or expensive, it is profitable to replace the performance variable with a highly correlated surrogate variable. In this paper we propose screening procedures using a surrogate variable with specified producer's and consumer's risks. Blending the basic concepts of acceptance sampling plans and screening procedures, the proposed model can be used effectively by quality professionals. Two models are considered: the normal model with dichotomous performance and continuous surrogate variables, and the bivariate normal model with continuous performance and surrogate variables. It is assumed the surrogate variable given the performance variable is normally distributed in the normal model, and performance and surrogate variables are jointly normally distributed in the bivariate normal model. For the two models, Producer's and consumer's risks are derived, and methods of finding the optimal screening procedures are presented. Numerical examples are also given.

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