• Title/Summary/Keyword: Interactive Simulations

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The Characteristics of Signal versus Noise SST Variability in the North Pacific and the Tropical Pacific Ocean

  • Yeh, Sang-Wook;Kirtman, Ben P.
    • Ocean Science Journal
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    • v.41 no.1
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    • pp.1-10
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    • 2006
  • Total sea surface temperature (SST) in a coupled GCM is diagnosed by separating the variability into signal variance and noise variance. The signal and the noise is calculated from multi-decadal simulations from the COLA anomaly coupled GCM and the interactive ensemble model by assuming both simulations have a similar signal variance. The interactive ensemble model is a new coupling strategy that is designed to increase signal to noise ratio by using an ensemble of atmospheric realizations coupled to a single ocean model. The procedure for separating the signal and the noise variability presented here does not rely on any ad hoc temporal or spatial filter. Based on these simulations, we find that the signal versus the noise of SST variability in the North Pacific is significantly different from that in the equatorial Pacific. The noise SST variability explains the majority of the total variability in the North Pacific, whereas the signal dominates in the deep tropics. It is also found that the spatial characteristics of the signal and the noise are also distinct in the North Pacific and equatorial Pacific.

Analysis of Output Characteristics and Design of LC Filter for Line-Interactive 3-Phase APF (3상 라인인터액티브형 능동전력필터 시스템을 위한 LC필터 출력특성 해석 및 설계)

  • 김응진
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.127-132
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    • 2000
  • This paper describes a 3-phase Line-Interactive APF system and analyzes its operating characteristics considering LC Filter output characteristics. Topology of APF is similar to that of Off-Line UPS in the point of parallelly operating inverter system. So it is possible to be multi-functioned active compensating system according to power condition. Likewise this actively operating system from APF to UPS and vice versa is often to be called Line-Interactive system. And more than that Line-Interactive system needs precise design of LC filter on converter output side to make this system fully operate in both APF and UPS modes. The problem in this point is how to design LC Filter to be contented with two different system characteristics so this paper analyzes this problem and proposes its design procedures. Then suggested filter design is verified to be contented by the simulations and experimental results

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Memory Allocation in Mobile Multitasking Environments with Real-time Constraints

  • Hyokyung, Bahn
    • International Journal of Internet, Broadcasting and Communication
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    • v.15 no.1
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    • pp.79-84
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    • 2023
  • Due to the rapid performance improvement of smartphones, multitasking on mobile platforms has become an essential feature. Unlike traditional desktop or server environments, mobile applications are mostly interactive jobs where response time is important, and some applications are classified as real-time jobs with deadlines. When interactive and real-time jobs run concurrently, memory allocation between multitasking applications is a challenging issue as they have different time requirements. In this paper, we study how to allocate memory space when real-time and interactive jobs are simultaneously executed in a smartphone to meet the multitasking requirements between heterogeneous jobs. Specifically, we analyze the memory size required to satisfy the constraints of real-time jobs and present a new model for allocating memory space between heterogeneous multitasking jobs. Trace-driven simulations show that the proposed model provides reasonable performance for interactive jobs while guaranteeing the requirement of real-time jobs.

A Study on Decoupling Methods in Cold Rolling Mill (냉연시스뎀의 비간섭화 기법에 관한 연구)

  • 이관호;심재훈;권욱현;최승갑;박철재
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.220-220
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    • 2000
  • In this paper, some non-interaction problems in tandem cold rolling mill are considered, which are required to control effectively a thickness of the cold .oiled strip. First, Interstand non-interactive compensate. (Interstand NIC) is designed for decoupling the interaction between stands. Next, a L2 optimization based pre-compensator is designed for decoupling the interaction between roll gap and strip tension in the stand. Finally, the effectness of the proposed decoupling methods is demonstrated via simulations.

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Three-Phase Line-Interactive Dynamic Voltage Restorer with a New Sag Detection Algorithm

  • Jeong, Jong-Kyou;Lee, Ji-Heon;Han, Byung-Moon
    • Journal of Power Electronics
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    • v.10 no.2
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    • pp.203-209
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    • 2010
  • This paper describes the development of a three-phase line-interactive DVR with a new sag detection algorithm. The developed detection algorithm has a hybrid structure composed of an instantaneous detector and RMS-variation detectors. The source voltage passes through the sliding-window DFT and RMS calculator, and the instantaneous sag detector. If an instantaneous sag is detected, the RMS variation detector-1 is selected to calculate the RMS variation. The RMS variation detector-2 is selected when the instantaneous sag occurs under the operation of the RMS variation detector-1. The feasibility of the proposed algorithm is verified through computer simulations and experimental work with a prototype of a line-interactive DVR with a 3kVA rating. The line-interactive DVR with the proposed algorithm can compensate for an input voltage sag or an interruption within a 2ms delay. The developed DVR can effectively compensate for a voltage sag or interruption in sensitive loads, such as computers, communications equipment, and automation equipment.

A Data Fault Detection System for Diesel Engines Using Neural Networks (신경회로망을 이용한 디젤기관의 데이터 이상감지 시스템에 관한 연구)

  • 천행춘;유영호
    • Journal of Advanced Marine Engineering and Technology
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    • v.26 no.4
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    • pp.493-500
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    • 2002
  • The operational data of diesel generator engine is two kinds of data. One is interactive the other is non interactive. We can find the fault information from interactive data measured for every sampling time when the changing rate, direction and status of data are investigated in comparition with those of normal status to diagnose the fault of combustion system. The various data values of combustion system for diesel engine are not proportional to load condition. The criterion to decide the level of data value is not absolute but relative to relational data. This study proposes to compose malfunction diagnosis engine using neural networks to decide that level of data value is out of normal status with the data collected from generator engine of the ship using the commercial data mining tool. This paper investigates the real ship's operational data of diesel generator engine and confirms usefulness of fault detecting through simulations for fault detecting.

Improvement to Crack Retardation Models Using ″Interactive Zone Concept″

  • Lee, Ouk-Sub;Chen, Zhi-Wei
    • International Journal of Precision Engineering and Manufacturing
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    • v.3 no.4
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    • pp.72-77
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    • 2002
  • The load interaction effect can be best illustrated by the phenomenon of overload retardation. Some prediction methods for retardation are reviewed and the problems discussed in the present paper. The so-called under-load effect much of the retardation disappears if a very low level minimum stress follows the overload, is also of importance for a prediction model to work properly under random load spectrum. The concept of Interactive Zone (IZ) fully considering reversed plasticity during unloading was discussed. This IZ concept can be combined with existing models to derive some improved models that can naturally take account of the under-load effect. Some simulations by IZ improved models for test under complex load sequences including multiple overloads and both over/under loads are compared with test results. It is seen that the improvement by IZ concept greatly enhanced the ability of existing models to accommodate complex load interaction effects.

INTERACTIVE VISUALIZATION TECHNIQUES FOR A VIRTUAL REALITY BASED ANALSYIS OF SIMULATION RESULTS

  • Benolken, Paul;Graf, Holger;Rix, Joachim
    • Proceedings of the Korea Society for Simulation Conference
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    • 2001.10a
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    • pp.237-247
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    • 2001
  • In this paper we present an overview of existing state of the art visualization techniques fur the interactive analysis of results from numerical simulations and measurements. We describe the basic concepts and key ideas behind these different visualization methods in this paper. The potential of these techniques for an efficient integration into a virtual reality environment will be investigated. Furthermore we present our first demonstrator fur visualizing multiparametric data and give an outlook on our plans for further exploiting and developing these techniques in an upcoming project.

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An approach to the interactive design process using genetic algorithms

  • Okuno, Taku;Kakazu, Yukinori
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10b
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    • pp.281-284
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    • 1992
  • This paper is aiming to apply the Genetic Algorithms (GAs) to the interactive design. For that purpose, the scheme for utilizing the past design processes for the next interactive design process is proposed. In this scheme, the process consists of three phases: the searching phase, the tuning phase and the design phase. The first phase searches the optimal decision sequences for the past design instances by GAs. By the collected sequences, the second phase tunes the criteria of selecting decision sequences for the next design process. By this scheme, the implicit constraints satisfied in the past design can be applied to the next design. Finally, the computer simulations on the simple gear-train design were carried out to show the effectiveness of the scheme.

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Development of Three-Phase Line-Interactive Dynamic Voltage Restorer with Hybrid Detection Method (Hybrid 검출방식을 적용한 삼상 선로 응동형 DVR(Dynamic Voltage Restorer) 개발)

  • Jeong, Jong-Kyou;Han, Byung-Moon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.10
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    • pp.1954-1961
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    • 2009
  • This paper describes the development of a three-phase line-interactive dynamic voltage restorer with hybrid detection method, which is composed of three H-bridge inverter modules and super-capacitors. The operational feasibility was verified through computer simulations with PSCAD/EMTDC software, and experimental works with a 3kVA prototype. The developed system can compensate the input voltage sag and interruption within 2ms. The maximum allowable duration of voltage interruption is about 4 seconds. The developed system can be effectively used to compensate the voltage interruption in the sensitive load, such as computer, communication devices, and automation devices, and medical equipment. The developed system has a simple structure to be easily implemented with commercially available components, and to be highly reliable in operation.