• Title/Summary/Keyword: network flow model

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A Study on the Groundwater Flow in Fractured-Porous Media by Flow Resistance Theory (단열-다공암반에서 유동저항 이론을 이용한 지하수 유동 평가에 관한 연구)

  • Han Ji-Woong;Hwang Yong-Soo;Kang Chul-Hyung
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.06a
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    • pp.231-238
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    • 2005
  • On the basis of flow resistance theory the conceptual model and related mathematical descriptions is proposed for resistance modeling of groundwater flow in CPM(continuum Porous medium), DFN(discrete fracture network) and fractured-porous medium. The proposed model is developed on the basis of finite volume method assuming steady-state, constant density groundwater flow. The basic approach of the method is to evaluate inter-block flow resistance values for a staggered grid arrangement, i.e. fluxes are stored at cell walls and scalars at cell centers. The balance of forces, i.e. the Darcy law, is utilized for each control volume centered around the point where the velocity component is stored. The transmissivity (or permeability) at the interface is assumed to be the harmonic average of neighboring blocks. Flow resistance theory was utilized to relate the fluxes between the grid blocks with residual pressures. The flow within porous medium is described by three dimensional equations and that within an individual fracture is described by a two dimensional equivalent of the flow equations for a porous medium. Newly proposed models would contribute to develop flow simulation techniques with various matrix characteristics.

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An IMS based Architecture Using SDN Controller (SDN 제어기를 사용한 IMS 기반 구조)

  • Liu, Zeqi;Lee, Jae-Oh
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.8
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    • pp.19-24
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    • 2018
  • The IP Multimedia Subsystem(IMS) is an architectural framework for delivering IP multimedia services to mobile users. In order to guarantee the reliability and Quality of Service(QoS) of a variety of multimedia services, we need a new evolutionary approach that maintains the IMS based signaling platform which can perform the processing of flow through distributed controllers. Software Defined Network(SDN) is an architecture purporting to be distributed, dynamic, cost-effectives as well as adapting and seeking to be suitable for the high-bandwidth, dynamic nature of today's applications. It requires some methods for the control plane to communication with the data plane. One of such mechanisms is OpenFlow which is a prominent standard protocol and interface that is responsible for managing the network resources by using the remote SDN controller. In this paper, we propose a straightforward approach for integrating SDN technology together with the IMS architecture. Therefore we propose and construct a combined architecture model that performs flow processing using OpenFlow via the IMS based signaling platform, which maintains the existing telecom call service. Additionally, we describe some relevant experimentation results from the proposed architecture.

A Study on User Satisfaction in the Mobile Navigation Systems of National Museum of Korea : Focused on Flow Theory (국립중앙박물관 네비게이션시스템 이용자 만족도 연구: 플로우개념을 중심으로)

  • Kim, Hak-Hee;Lee, Ki-Dong
    • The Journal of Information Systems
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    • v.18 no.2
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    • pp.19-34
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    • 2009
  • The purpose of this study is to analyze the influence of the flow concepts to the visitor's satisfaction in the mobile sensor-network navigation system. recently installed in the National Museum of Korea in Seoul. The satisfaction of visitor's on the facilities and services offered by the museum environment is crucial in that it provides a value-added learning experience for the visitor to immerse into the historical descriptions and cultural contents, often presented in digital formats. 200 subjects' data are analyzed using the structural equation model and the key results are presented. It is hoped thai our flow results show a new way of understanding of information technologies applied to the museum setting.

An Exploratory Study for Investigating Relationship between Players′ Intention to Play, Flow and Interactivity in On-line Games (온라인 게임의 향후 이용의도, 플로우, 상호작용성에 관한 실증적 연구)

  • 엄명용;김태웅
    • Journal of Technology Innovation
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    • v.12 no.1
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    • pp.241-269
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    • 2004
  • Online game business has emerged as the most lucrative entertainment industry, with over 10 million players in South Korea. The popularity of online games can be attributed to the availability of broadband network and the presence of numerous PC Bangs and around the country, which have pushed online games into the mainstream entertainment culture. The age distribution of online game players is expanding and a variety of new games are under development to target certain age groups. While the interactive entertainment market continues to expand, with many new online game publishers entering the market, relatively little is known about which factors influence online game players' behavioral intentions to play continuously n this area. It appears that in this extremely attractive and growing services segment, academics, as well as practitioners, would benefit from investigating the relationships among the players' intentions to play, flow, and the impacts of several other key game-related constructs n consumer behavioral intentions. Several types of interaction in on-line games and their relationship with the flow construct are investigated, and the resulting conceptual model is proposed. Based on data collected from online questionnaire survey, the validity of the simultaneous equation model has been tested and interesting conclusions have been developed concerning the relationships between the players' behavioral intentions to play, flow, and interactions. Other interesting results concerning game development strategy are also provided.

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Predicting the lateral displacement of tall buildings using an LSTM-based deep learning approach

  • Bubryur Kim;K.R. Sri Preethaa;Zengshun Chen;Yuvaraj Natarajan;Gitanjali Wadhwa;Hong Min Lee
    • Wind and Structures
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    • v.36 no.6
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    • pp.379-392
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    • 2023
  • Structural health monitoring is used to ensure the well-being of civil structures by detecting damage and estimating deterioration. Wind flow applies external loads to high-rise buildings, with the horizontal force component of the wind causing structural displacements in high-rise buildings. This study proposes a deep learning-based predictive model for measuring lateral displacement response in high-rise buildings. The proposed long short-term memory model functions as a sequence generator to generate displacements on building floors depending on the displacement statistics collected on the top floor. The model was trained with wind-induced displacement data for the top floor of a high-rise building as input. The outcomes demonstrate that the model can forecast wind-induced displacement on the remaining floors of a building. Further, displacement was predicted for each floor of the high-rise buildings at wind flow angles of 0° and 45°. The proposed model accurately predicted a high-rise building model's story drift and lateral displacement. The outcomes of this proposed work are anticipated to serve as a guide for assessing the overall lateral displacement of high-rise buildings.

Analytical Approach of New Random-walk Based Mobility Management Scheme in IP-based Mobile Networks

  • Song, Myungseok;Cho, Jun-Dong;Jeong, Jongpil
    • International Journal of Advanced Culture Technology
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    • v.2 no.1
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    • pp.1-13
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    • 2014
  • In next-generation wireless networks, provisioning of IP-based network architecture and seamless transmission services are very important issues for mobile nodes. For this reason, a mobility management mechanism to support global roaming is highly regarded. These technologies bring a broader life by using a global roaming account through the connection of multiple devices or technology to mobile users; they also provide real-time multimedia services. This paper presents a comprehensive performance analysis of fast handover for hierarchical mobile IPv6 (F-HMIPv6), hierarchical mobile IPv6 (HMIPv6), Proxy Mobile IPv6 (PMIPv6), and fast Proxy Mobile IPv6 (FPMIPv6) using the fluid-flow model and random-walk model. As a result, the location update cost of the PMIPv6 and FPMIPv6 is better than that of HMIPv6 and F-HMIPv6. These results suggest that the network-based mobility management technology is superior to the hierarchical mobility management technology in the mobility environment.

A Study on Development of the Integrated Information Network Model for Knowledge and Information Resources Sharing (지식정보 공유를 위한 통합정보망 구축 모형 개발에 관한 연구)

  • 정동열
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.14 no.2
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    • pp.119-140
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    • 2003
  • The purpose of this paper is to suggest guidelines for building up an integrated information network(IIN) model that enables to enhance production, flow and use of knowledge and information. The IIN consists of four areas of key infrastructure, such as, education, labor market, school-industry cooperation, and lifelong education information infrastructure. Based on the analysis of current situations and problems of each information infrastructure, this paper raises variety of issues and solutions for the IIN model. Directions for building up the IIN includes both information base infrastructure and information support infrastructure.

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Development of the Contingency Analysis Program of Korean Energy Management System (한국형 에너지 관리시스템용 상정고장 해석프로그램 개발)

  • Cho, Yoon-Sung;Yun, Sang-Yun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.2
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    • pp.232-241
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    • 2010
  • This paper describes the development of robust contingency analysis program for Korean Energy Management System. The important function of contingency analysis is to determine the bus/branch model for contingency, and to calculate the state of the power network based on the network model and topology output. In the proposed method, the bus/branch models for contingencies are determined exactly using a fast linked-list method based on the application common model database. To calculate the state of the power system included contingency, the full-decoupled powerflow approach, the partial powerflow method for contingencies and the proposed contingency screening algorithm are also used to contingency analysis. To verify the performance of the developed processor, we performed a file-based test using several structured input data and online test using the database which resides on memory. The results of these comprehensive tests showed that the developed processors can accurately calculate the power system contingency state from online data and can be applied to Korea Power Exchange system.

Artificial Neural Network Models for Optimal Start and Stop of Chiller and AHU (인공신경망 모델을 이용한 냉동기 및 공조기 최적 기동/정지 제어)

  • Park, SungHo;Ahn, Ki Uhn;Hwang, Aaron;Choi, Sunkyu;Park, Cheol Soo
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.35 no.2
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    • pp.45-52
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    • 2019
  • BEMS(Building Energy Management Systems) have been applied to office buildings and collect relevant building energy data, e.g. temperatures, mass flow rates and energy consumptions of building mechanical systems and indoor spaces. The aforementioned measured data can be beneficially utilized for developing data-driven machine learning models which can be then used as part of MPC(Model Predictive Control) and/or optimal control strategies. In this study, the authors developed ANN(Artificial Neural Network) models of an AHU (Air Handling Unit) and a chiller for a real-life office building using BEMS data. Based on the ANN models, the authors developed optimal control strategies, e.g. daily operation schedule with regard to optimal start and stop of the AHU and the chiller (500 RT). It was found that due to the optimal start and stop of the AHU and the chiller, 4.5% and 16.4% of operation hours of the AHU and the chiller could be saved, compared to an existing operation.

A Study on Real-time Drilling Parameters Prediction Using Recurrent Neural Network (순환신경망을 이용한 실시간 시추매개변수 예측 연구)

  • Han, Dong-kwon;Seo, Hyeong-jun;Kim, Min-soo;Kwon, Sun-il
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.05a
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    • pp.204-206
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    • 2021
  • Real-time drilling parameters prediction is a considerably important study from the viewpoint of maximizing drilling efficiency. Among the methods of maximizing drilling, the method of improving the drilling speed is common, which is related to the rate of penetration, drillstring rotational speed, weight on bit, and drilling mud flow rate. This study proposes a method of predicting the drilling rate, one of the real-time drilling parameters, using a recurrent neural network-based deep learning model, and compares the existing physical-based drilling rate prediction model with a prediction model using deep learning.

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