• Title/Summary/Keyword: Engineering change

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Sensorless Speed Control of Induction Motor using Am and FMRLC (ANN과 FMRLC를 이용한 유도전동기의 센서리스 속도제어)

  • Nam Su-Myeong;Lee Jung-Chul;Lee Hong-Gyun;Lee Young-Sil;Part Bung-Sang;Chung Dong-Hwa
    • Proceedings of the KIPE Conference
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    • 2004.07a
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    • pp.38-41
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    • 2004
  • Artificial intelligence control that use Fuzzy, Neural network, genetic algorithm etc. in the speed control of induction motor recently is studied much. Also, sensors such as Encoder and Resolver are used to receive the speed of induction motor and information of position. However, this control method or sensor use receives much effects in surroundings environment change and react sensitively to parameter change of electric motor and control Performance drops. Presume the speed and position of induction motor by ANN in this treatise, and because using FMRLC that is consisted of two Fuzzy Logic, can correct Fuzzy Rule Base through teaming and save good response special quality in change of condition such as change of parameter.

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A statistical framework with stiffness proportional damage sensitive features for structural health monitoring

  • Balsamo, Luciana;Mukhopadhyay, Suparno;Betti, Raimondo
    • Smart Structures and Systems
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    • v.15 no.3
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    • pp.699-715
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    • 2015
  • A modal parameter based damage sensitive feature (DSF) is defined to mimic the relative change in any diagonal element of the stiffness matrix of a model of a structure. The damage assessment is performed in a statistical pattern recognition framework using empirical complementary cumulative distribution functions (ECCDFs) of the DSFs extracted from measured operational vibration response data. Methods are discussed to perform probabilistic structural health assessment with respect to the following questions: (a) "Is there a change in the current state of the structure compared to the baseline state?", (b) "Does the change indicate a localized stiffness reduction or increase?", with the latter representing a situation of retrofitting operations, and (c) "What is the severity of the change in a probabilistic sense?". To identify a range of normal structural variations due to environmental and operational conditions, lower and upper bound ECCDFs are used to define the baseline structural state. Such an approach attempts to decouple "non-damage" related variations from damage induced changes, and account for the unknown environmental/operational conditions of the current state. The damage assessment procedure is discussed using numerical simulations of ambient vibration testing of a bridge deck system, as well as shake table experimental data from a 4-story steel frame.

Analysis of Land Use Change Impact on Storm Runoff in Anseongcheon Watershed

  • Park, Geun-Ae;Jung, In-Kyun;Lee, Mi-Seon;Shin, Hyung-Jin;Park, Jong-Yoon;Kim, Seong-Joon
    • Korean Journal of Remote Sensing
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    • v.24 no.1
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    • pp.35-43
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    • 2008
  • The purpose of this study is to evaluate the hydrological impact due to temporal land cover change by gradual urbanization of upstream watershed of Pyeongtaek gauging station of Anseong-cheon. WMS HEC-1 was adopted, and OEM with 200 m resolution and hydrologic soil group from 1:50,000 scale soil map were prepared. Land covers of 1986, 1990, 1994 and 1999 Landsat TM images were classified by maximum likelihood method. The watershed showed a trend that forest & paddy areas decreased and urban/residential area gradually increased during the four selected years. The model was calibrated at 2 locations (Pyeonglaek and Gongdo) by comparing observed with simulated discharge results for 5 summer storm events from 1998 to 2001. The watershed average CN values varied from 61.7 to 62.3 for the 4 selected years. To identify the impact of streamflow by temporal area change of a target land use, a simple evaluation method that the CN values of areas except the target land use are unified as one representative CN value was suggested. By applying the method, watershed average CN value was affected in the order of paddy, forest and urban/residential, respectively.

ANALYZING EFFECTIVE FACTOR OF THE CHANGE MANAGEMENT BASED ON URBAN REGENERATION PROJECT IN REPUBLIC OF KOREA

  • Jae-Pil Seo;Yoon-Ki Choi;Bo-Sik Son;Han-Guk Ryu
    • International conference on construction engineering and project management
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    • 2011.02a
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    • pp.591-596
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    • 2011
  • There are quite a number of business processes in the urban regeneration project. Managers and participants who involved in the project make and use information for the best way to perform in the particular business process. The information can be also reused and produced for data at the next stage. Accordingly, the information sometimes goes out of existence and work data up into new information when the urban regeneration project has been accomplished. But in that case some of changes happen occasionally, the business for urban regeneration has suffered a loss of profit and time as result of confusions about decisions and inappropriate action. For that reason, the information should be analyzed to achieve its aim at the business process under the influence of changes. Then, even though detail processes and management method change, the Core Information, which are important factors for accomplishing the project, help that the project can be operated to solve the problem about confusion and loss of the business. In conclusion, the Core Information is main effective factors for successful urban regeneration projects on the change management. The purpose of this study is to research the information according to the Information-flow and changes, and to find out the influence factors and the Core Information to manage efficiently at the process of urban regeneration projects.

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Enhancement of Land Load Estimation Method in TMDLs for Considering of Climate Change Scenarios (기후변화를 고려하기 위한 오염총량관리제 토지계 오염부하량 산정 방식 개선)

  • Ryu, Jichul;Park, Yoon Sik;Han, Mideok;Ahn, Ki Hong;Kum, Donghyuk;Lim, Kyoung Jae;Park, Bae Kyung
    • Journal of Korean Society on Water Environment
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    • v.30 no.2
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    • pp.212-219
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    • 2014
  • In this study, a land pollutant load calculation method in TMDLs was improved to consider climate change scenarios. In order to evaluate the new method, future change in rainfall patterns was predicted by using SRES A1B climate change scenarios and then post-processing methods such as change factor (CF) and quantile mapping (QM) were applied to correct the bias between the predicted and the observed rainfall patterns. Also, future land pollutant loads were estimated by using both the bias corrected rainfall patterns and the enhanced method. For the results of bias correction, both methods (CF and QM) predicted the temporal trend of the past rainfall patterns and QM method showed future daily average precipitation in the range of 1.1~7.5 mm and CF showed it in the range of 1.3~6.8 mm from 2014 to 2100. Also, in the result of the estimation of future land pollutant loads using the enhanced method (2020, 2040, 2100), TN loads were in the range of 4316.6~6138.6 kg/day and TP loads were in the range of 457.0~716.5 kg/day. However, each result of TN and TP loads in 2020, 2040, 2100 was the same with the original method. The enhanced method in this study will be useful to predict land pollutant loads under the influence of climate change because it can reflect future change in rainfall patterns. Also, it is expected that the results of this study are used as a base data of TMDLs in case of applying for climate change scenarios.

Change Attention based Dense Siamese Network for Remote Sensing Change Detection (원격 탐사 변화 탐지를 위한 변화 주목 기반의 덴스 샴 네트워크)

  • Hwang, Gisu;Lee, Woo-Ju;Oh, Seoung-Jun
    • Journal of Broadcast Engineering
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    • v.26 no.1
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    • pp.14-25
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    • 2021
  • Change detection, which finds changes in remote sensing images of the same location captured at different times, is very important because it is used in various applications. However, registration errors, building displacement errors, and shadow errors cause false positives. To solve these problems, we propose a novle deep convolutional network called CADNet (Change Attention Dense Siamese Network). CADNet uses FPN (Feature Pyramid Network) to detect multi-scale changes, applies a Change Attention Module that attends to the changes, and uses DenseNet as a feature extractor to use feature maps that contain both low-level and high-level features for change detection. CADNet performance measured from the Precision, Recall, F1 side is 98.44%, 98.47%, 98.46% for WHU datasets and 90.72%, 91.89%, 91.30% for LEVIR-CD datasets. The results of this experiment show that CADNet can offer better performance than any other traditional change detection method.

An On-Line Real-Time SPC Scheme and Its Performance

  • Nishina, Ken
    • International Journal of Quality Innovation
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    • v.2 no.1
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    • pp.30-49
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    • 2001
  • This paper considers a recent environment in the manufacturing process in which data in large amounts can be obtained on-line in real-time. Under this environment an on-line real-time Statistical Process Control (SPC) scheme equipped with detection of a process change, change-point estimation, and recognition of the change pattern is proposed. The proposed SPC scheme is composed of a Cusum chart, filtering methods and Akaike Information Criterion (AIC). We examine the performance of this scheme by Monte Carlo simulation and show its usefulness.

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A robust optical security system using polarization and phase masks

  • Kim, Jae-Hyun;Shin, Chang-Mok;Seo, Dong-Hoan;Kim, Jong-Yun;Park, Se-Joon;Kim, Soo-Joong
    • Proceedings of the IEEK Conference
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    • 2000.07b
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    • pp.919-922
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    • 2000
  • A robust optical security technique using ortho-gonally polarized lights in the interferometer is proposed. We use orthogonally polarized lights in order to minimize the noise generated by the refractive index change due to vibration, flow of air, change of temperature etc. To make orthogonally polarized lights the first beam splitter in the Mach-Zehnder interferometer is substituted by a polarizing beam splitter(PBS). Because of incoherence of orthogonally polarized lights, the noise generated by the change of refractive index is minimized. To encrypt an image we use the random partition and the diffusing of pixel. Finally we make Phase-only-filters of each image which is randomly partitioned and diffused pixel by pixel. Simulation results show the proposed system has the ability of encryption and decryption of an image.

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Propagation of Engineering Changes for Supporting Consistent Product Data View (일관된 제품자료관점을 지원하는 설계변경 전달에 관한 연구)

  • 도남철
    • Korean Journal of Computational Design and Engineering
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    • v.8 no.2
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    • pp.90-100
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    • 2003
  • Engineering change (EC) objects are the data structure and related operations that can support applications for EC procedures or processes. Their functionalities include controlling management data, specifying related product structure, and archiving a history of product structure changes for EC management. In this paper we introduce a systematic approach to support the propagation of changes between different product structure views using the history of structure changes in EC objects. The change propagations supported by EC objects enable designers to maintain the consistency of multiple product structure views for engineering, manufacturing or even customer support applications. This paper also includes EC examples and experimental implementations for the proposed EC objects.

Tsunami-induced Change Detection Using SAR Intensity and Texture Information Based on the Generalized Gaussian Mixture Model

  • Jung, Min-young;Kim, Yong-il
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.2
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    • pp.195-206
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    • 2016
  • The remote sensing technique using SAR data have many advantages when applied to the disaster site due to its wide coverage and all-weather acquisition availability. Although a single-pol (polarimetric) SAR image cannot represent the land surface better than a quad-pol SAR image can, single-pol SAR data are worth using for disaster-induced change detection. In this paper, an automatic change detection method based on a mixture of GGDs (generalized Gaussian distribution) is proposed, and usability of the textural features and intensity is evaluated by using the proposed method. Three ALOS/PALSAR images were used in the experiments, and the study site was Norita City, which was affected by the 2011 Tohoku earthquake. The experiment results showed that the proposed automatic change detection method is practical for disaster sites where the large areas change. The intensity information is useful for detecting disaster-induced changes with a 68.3% g-mean, but the texture information is not. The autocorrelation and correlation show the interesting implication that they tend not to extract agricultural areas in the change detection map. Therefore, the final tsunami-induced change map is produced by the combination of three maps: one is derived from the intensity information and used as an initial map, and the others are derived from the textural information and used as auxiliary data.