• Title/Summary/Keyword: Phase Identification

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An Extraction of the Risk Events in the Construction Planning Phase (건설기획단계에서의 위험요인 도출)

  • Kwon, Soon-O;Kim, Seon-Gyoo;Lee, Nak-Woon
    • Journal of Industrial Technology
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    • v.25 no.B
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    • pp.99-106
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    • 2005
  • The planning phase of construction project success or failure of the enterprise decision the 1st dangerous duration which occurs very there is a possibility of making with the phase which is important, of construction project in life cycle most many risk. But the risk management from planning phase well does not become accomplished is the actual condition from existing construction project. Consequently, it classifies the risk event from project initial planning phase of construction project from this study which probably is substantial risk event the possibility of accomplishing from a planning phase successfully in order to be.

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A Study on the Application of SVD to an Inverse Problem in a Cantilever Beam with a Non-minimum Phase (비최소 위상을 갖는 외팔보에서 SVD를 이용한 역변환 문제에 관한 연구)

  • 이상권;노경래;박진호
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.11 no.9
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    • pp.431-438
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    • 2001
  • This paper present experimental results of source identification for non-minimum phase system. Generally, a causal linear system may be described by matrix form. The inverse problem is considered as a matrix inversion. Direct inverse method can\`t be applied for a non-minimum phase system, the reason is that the system has ill-conditioning. Therefore, in this study to execute an effective inversion, SVD inverse technique is introduced. In a Non-minimum phase system, its system matrix may be singular or near-singular and has one more very small singular values. These very small singular values have information about a phase of the system and ill-conditioning. Using this property we could solve the ill-conditioned problem of the system and then verified it for the practical system(cantilever beam). The experimental results show that SVD inverse technique works well for non-minimum phase system.

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Product Phase Control During Interdiffusion Reactions (상호 확산 반응 중의 생성상 제어)

  • Park, Joon-Sik;Kim, Ji-Hoon;Perepezko, John R.
    • Journal of Korea Foundry Society
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    • v.26 no.1
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    • pp.27-33
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    • 2006
  • Phase evolutions involving nucleation stages together with diffusional growth have been examined in order to provide a guideline for determining rate limiting stages during phase evolutions. In multiphase materials systems in coatings, composites or multilayered structures, diffusion treatments often result in the development of metastable/intermediate phases at the reaction interfaces. The development of metastable phases during solid state interdiffusion demonstrates that the nucleation reaction can be one controlling factor. Also, the concentration gradient and the relative magnitudes of the component diffusivities provide a basis for a phase selection and the application of a kinetic bias strategy in the phase selection. For multicomponent alloy systems, the identification of the operative diffusion pathway is central to control phase formation. Experimental access to the nucleation and growth stage is discussed in thin film multi layers and bulk samples.

EXTENSION OF CFD CODES APPLICATION TO TWO-PHASE FLOW SAFETY PROBLEMS

  • Bestion, Dominique
    • Nuclear Engineering and Technology
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    • v.42 no.4
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    • pp.365-376
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    • 2010
  • This paper summarizes the results of a Writing Group on the Extension of CFD codes to two-phase flow safety problems, which was created by the Group for Analysis and Management of Accidents of the Nuclear Energy Agency' Committee on the Safety of Nuclear Installations (NEA-CSNI). Two-phase CFD used for safety investigations may predict small scale flow processes, which are not seen by system thermalhydraulic codes. However, the two-phase CFD models are not as mature as those in the single phase CFD and potential users need some guidance for proper application. In this paper, a classification of various modelling approaches is proposed. Then, a general multi-step methodology for using two-phase-CFD is explained, including a preliminary identification of flow processes, a model selection, and a verification and validation process. A list of 26 nuclear reactor safety issues that could benefit from investigations at the CFD scale is identified. Then, a few issues are analyzed in more detail, and a preliminary state-of-the-art is proposed and the remaining gaps in the existing approaches are identified. Finally, guidelines for users are proposed.

A Design of Device Management System for Factories using Wireless Sensor Network (무선 센서 망을 이용한 공장 내 장치 관리 시스템 설계)

  • Moon, Sung-Nam;Kim, Young-Han
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.3C
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    • pp.233-240
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    • 2012
  • Unlike traditional factory environment, in an industrial factory network applied wireless sensor network technologies, all procedures of discovery, identification and verification of devices should be performed in an automatic fashion. To address these challenges, we design a management system using the device registry server that we propose in this paper. In the phase of device discovery, the proposed system utilizes properties of routing protocol running in factories. Also, in the phase of identification and verification, the system uses unique and general information of a device stored within the device registration server. Such a way allows management system to reduce implementation complexity and to easily manage devices in a factory applied with a wireless network consisting of heterogeneous devices.

A Study on Counterfeit Electronic Parts Identification and Verification Methods to Improve the Reliability of Weapons Systems in Mass Production Phase (양산단계 무기체계 신뢰성 향상을 위한 위조 전자부품 식별 및 검증 방안에 대한 연구)

  • Kim, Byung-Jun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.15 no.4
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    • pp.617-624
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    • 2020
  • Due to the rapid development of science technology and the main characteristics of the defense industry, such as long development period, design complexity, high possibility of discontinuing parts due to long life cycle, and small quantity production, it can cause increasing of the inflow possibility of counterfeit electronic parts and deteriorating the reliability of weapons systems. This paper presents the specific criteria for the identification of electronic parts to be verified for mass produced weapons systems after the development is completed, and the identification and verification methods for the inflow of counterfeit electronic components.

Detection and Identification of the Series Arc in an Indoor Wiring System (옥내 배선계통에서 직렬 아크의 검출과 판별)

  • Kim, Woo-Hyun;Wang, Guoming;Kil, Gyung-Suk;Ji, Hong-Keun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.6
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    • pp.412-416
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    • 2018
  • Most series arcs lead to electrical fires that cannot be interrupted by circuit breakers, because the arc's current is outside the breaker's operating range. In this paper, experiments were conducted on the detection and identification of series arcs to prevent electrical fires. Plugs and outlets specified in KS C 8305 were deteriorated to replicate arc faults commonly found in fields. The characteristics of series arcs resulting from various types of loose connections were determined by analyzing the frequency spectra and phase distributions of detected arc pulses. The results showed that the simulated arc defects used in this study were more similar to actual arc phenomena than the existing arc generator specified in UL 1699. In addition, loose connections, such as wire-wire, terminal-wire, and outlet-plug, can be identified by phases of $0^{\circ}$, $180^{\circ}$ and $360^{\circ}$, respectively. These phases can be detected by a band pass filter with a frequency range of 5~10 MHz, which can be used as the trip signal for circuit breakers.

AUTOMATED HAZARD IDENTIFICATION FRAMEWORK FOR THE PROACTIVE CONSIDERATION OF CONSTRUCTION SAFETY

  • JunHyuk Kwon;Byungil Kim;SangHyun Lee;Hyoungkwan Kim
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.60-65
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    • 2013
  • Introducing the concept of construction safety in the design/engineering phase can improve the efficiency and effectiveness of safety management on construction sites. In this sense, further improvements for safety can be made in the design/engineering phase through the development of (1) an automated hazard identification process that is little dependent on user knowledge, (2) an automated construction schedule generation to accommodate varying hazard information over time, and (3) a visual representation of the results that is easy to understand. In this paper, we formulate an automated hazard identification framework for construction safety by extracting hazard information from related regulations to eliminate human interventions, and by utilizing a visualization technique in order to enhance users' understanding on hazard information. First, the hazard information is automatically extracted from textual safety and health regulations (i.e., Occupational Safety Health Administration (OSHA) Standards) by using natural language processing (NLP) techniques without users' interpretations. Next, scheduling and sequencing of the construction activities are automatically generated with regard to the 3D building model. Then, the extracted hazard information is integrated into the geometry data of construction elements in the industry foundation class (IFC) building model using a conformity-checking algorithm within the open source 3D computer graphics software. Preliminary results demonstrate that this approach is advantageous in that it can be used in the design/engineering phases of construction without the manual interpretation of safety experts, facilitating the designers' and engineers' proactive consideration for improving safety management.

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GMM-Based Gender Identification Employing Group Delay (Group Delay를 이용한 GMM기반의 성별 인식 알고리즘)

  • Lee, Kye-Hwan;Lim, Woo-Hyung;Kim, Nam-Soo;Chang, Joon-Hyuk
    • The Journal of the Acoustical Society of Korea
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    • v.26 no.6
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    • pp.243-249
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    • 2007
  • We propose an effective voice-based gender identification using group delay(GD) Generally, features for speech recognition are composed of magnitude information rather than phase information. In our approach, we address a difference between male and female for GD which is a derivative of the Fourier transform phase. Also, we propose a novel way to incorporate the features fusion scheme based on a combination of GD and magnitude information such as mel-frequency cepstral coefficients(MFCC), linear predictive coding (LPC) coefficients, reflection coefficients and formant. The experimental results indicate that GD is effective in discriminating gender and the performance is significantly improved when the proposed feature fusion technique is applied.

A Method and Tool for Identifying Domain Components Using Object Usage Information

  • Lee, Woo-Jin;Kwon, Oh-Cheon;Kim, Min-Jung;Shin, Gyu-Sang
    • ETRI Journal
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    • v.25 no.2
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    • pp.121-132
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    • 2003
  • To enhance the productivity of software development and accelerate time to market, software developers have recently paid more attention to a component-based development (CBD) approach due to the benefits of component reuse. Among CBD processes, the identification of reusable components is a key but difficult process. Currently, component identification depends mainly on the intuition and experience of domain experts. In addition, there are few systematic methods or tools for component identification that enable domain experts to identify reusable components. This paper presents a systematic method and its tool called a component identifier that identifies software components by using object-oriented domain information, namely, use case models, domain object models, and sequence diagrams. To illustrate our method, we use the component identifier to identify candidates of reusable components from the object-oriented domain models of a banking system. The component identifier enables domain experts to easily identify reusable components by assisting and automating identification processes in an earlier development phase.

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