• Title/Summary/Keyword: high robustness

Search Result 887, Processing Time 0.024 seconds

Review on Quantitative Measures of Robustness for Building Structures Against Disproportionate Collapse

  • Jiang, Jian;Zhang, Qijie;Li, Liulian;Chen, Wei;Ye, Jihong;Li, Guo-Qiang
    • International Journal of High-Rise Buildings
    • /
    • v.9 no.2
    • /
    • pp.127-154
    • /
    • 2020
  • Disproportionate collapse triggered by local structural failure may cause huge casualties and economic losses, being one of the most critical civil engineering incidents. It is generally recognized that ensuring robustness of a structure, defined as its insensitivity to local failure, is the most acceptable and effective method to arrest disproportionate collapse. To date, the concept of robustness in its definition and quantification is still an issue of controversy. This paper presents a detailed review on about 50 quantitative measures of robustness for building structures, being classified into structural attribute-based and structural performance-based measures (deterministic and probabilistic). The definition of robustness is first described and distinguished from that of collapse resistance, vulnerability and redundancy. The review shows that deterministic measures predominate in quantifying structural robustness by comparing the structural responses of an intact and damaged structure. The attribute-based measures based on structural topology and stiffness are only applicable to elastic state of simple structural forms while the probabilistic measures receive growing interest by accounting for uncertainties in abnormal events, local failure, structural system and failure-induced consequences, which can be used for decision-making tools. There is still a lack of generalized quantifications of robustness, which should be derived based on the definition and design objectives and on the response of a structure to local damage as well as the associated consequences of collapse. Critical issues and recommendations for future design and research on quantification of robustness are provided from the views of column removal scenarios, types of structures, regularity of structural layouts, collapse modes, numerical methods, multiple hazards, degrees of robustness, partial damage of components, acceptable design criteria.

High-Robust Relaxation Oscillator with Frequency Synthesis Feature for FM-UWB Transmitters

  • Zhou, Bo;Wang, Jingchao
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.15 no.2
    • /
    • pp.202-207
    • /
    • 2015
  • A CMOS relaxation oscillator, with high robustness over process, voltage and temperature (PVT) variations, is designed in $0.18{\mu}m$ CMOS. The proposed oscillator, consisting of full-differential charge-discharge timing circuit and switched-capacitor based voltage-to-current conversion, could be expanded to a simple open-loop frequency synthesizer (FS) with output frequency digitally tuned. Experimental results show that the proposed oscillator conducts subcarrier generation for frequency-modulated ultra-wideband (FM-UWB) transmitters with triangular amplitude distortion less than 1%, and achieves frequency deviation less than 8% under PVT and phase noise of -112 dBc/Hz at 1 MHz offset frequency. Under oscillation frequency of 10.5 MHz, the presented design has the relative FS error less than 2% for subcarrier generation and the power dissipation of 0.6 mW from a 1.8 V supply.

High Performance of Induction Motor Drive using GAT (GAT를 이용한 유도전동기 드라이브의 고성능 제어)

  • Ko, Jae-Sub;Nam, Su-Myeong;Choi, Jung-Sik;Park, Bung-Sang;Chung, Dong-Hwa
    • Proceedings of the KIEE Conference
    • /
    • 2005.10c
    • /
    • pp.202-204
    • /
    • 2005
  • This paper is proposed genetic algorithm tuning(GAT) controller for high performance of induction motor drive. We employed GA to the classical PI controller. The approach having ability for global optimization and with good robustness, is expected to overcome some weakness of conventional approaches and to be more acceptable for industrial practices. The control performance of the GAT PI controller is evaluated by analysis for various operating conditions. The results of experiment prove that the proposed control system has strong high performance and robustness to parameter variation, and steady-state accuracy and transient response.

  • PDF

Block Based Blind & Secure Gray Image Watermarking Technique Based on Discrete Wavelet Transform and Singular Value Decomposition

  • Imran, Muhammad;Harvey, Bruce A.
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.11 no.2
    • /
    • pp.883-900
    • /
    • 2017
  • In this paper block based blind secure gray image watermarking scheme based on discrete wavelet transform and singular value decomposition is proposed. In devising the proposed scheme, security is given high importance along with other two requirements: robustness and imperceptibility. The use of discrete wavelet transform not only improves robustness but the selection of bands with high tolerance towards noise caused an improvement in terms of imperceptibility. The robustness further improved due to the involvement of singular vectors along with singular values in watermark embedding and extraction process. Finally, to achieve security, the selected DWT band is decomposed into smaller blocks and random blocks are chosen for modification. Furthermore, the elements of left and right singular vectors of selected blocks are chosen based on their dependence upon each other for watermark embedding. Various experiments using different images as host and watermark were conducted to examine and validate the proposed technique. Additionally, the proposed technique is tested against various attacks like compression, affine transformation, cropping, translation, X shearing, scaling, Y shearing, filtering, blurring, different kinds of noises, histogram equalization, rotation, etc. Lastly, the proposed technique is compared with state-of-the-art watermarking techniques and their comparison shows significant improvement of proposed scheme over existing techniques.

Performance and Robustness of Control Charting Methods for Autocorrelated Data

  • Chin, Chang-Ho;Apley, Daniel W.
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.34 no.2
    • /
    • pp.122-139
    • /
    • 2008
  • With the proliferation of in-process measurement technology, autocorrelated data are increasingly common in industrial SPC applications. A number of high performance control charting techniques that take into account the specific characteristics of the autocorrelation through time series modeling have been proposed over the past decade. We present a survey of such methods and analyze and compare their performances for a range of typical autocorrelated process models. One practical concern with these methods is that their performances are often strongly affected by errors in the time series models used to represent the autocorrelation. We also provide some analytical results comparing the robustness of the various methods with respect to time series modeling errors.

Frequency-Temporal Filtering for a Robust Audio Fingerprinting Scheme in Real-Noise Environments

  • Park, Man-Soo;Kim, Hoi-Rin;Yang, Seung-Hyun
    • ETRI Journal
    • /
    • v.28 no.4
    • /
    • pp.509-512
    • /
    • 2006
  • In a real environment, sound recordings are commonly distorted by channel and background noise, and the performance of audio identification is mainly degraded by them. Recently, Philips introduced a robust and efficient audio fingerprinting scheme applying a differential (high-pass filtering) to the frequency-time sequence of the perceptual filter-bank energies. In practice, however, the robustness of the audio fingerprinting scheme is still important in a real environment. In this letter, we introduce alternatives to the frequency-temporal filtering combination for an extension method of Philips' audio fingerprinting scheme to achieve robustness to channel and background noise under the conditions of a real situation. Our experimental results show that the proposed filtering combination improves noise robustness in audio identification.

  • PDF

Improved Reliable SVD-Based Watermark Scheme For Ownership Verification (소유권 확인을 위한 향상된 고신뢰성 SVD 기반 워터마킹기법)

  • Luong, Ngoc Thuy Dung;Sohn, Won
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2016.11a
    • /
    • pp.82-84
    • /
    • 2016
  • We propose a new reliable SVD-based watermarking scheme having high fidelity and strong robustness with no false-positive problem. Each column of the principal component of a watermark image is embedded into singular values of LL, LH, HL and HH sub-bands of cover image with different scale factors. Each scale factor is optimized by trading-off fidelity and robustness using Differential Evolution (DE) algorithm. The proposed scheme improves fidelity and robustness of existing reliable SVD based watermarking schemes without any false-positive problem. Index Terms - watermarking, reliable SVD, DWT, principal component, Differential Evolution.

  • PDF

On the Robustness of Disturbance Observer based Controller for DC Motor with Unstructured Uncertainty (비구조적 불확실성이 존재하는 DC모터에 대한 외란관측기 기반 제어기의 강인성에 대한 연구)

  • Jo, Nam-Hoon
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.66 no.1
    • /
    • pp.66-71
    • /
    • 2017
  • In this paper, we study the robustness of disturbance observer based controller for DC motor in the presence of unmodeled dynamics. It is well known that the robustness property usually becomes weaker as the control gain becomes larger. On the contrary to this expectation, it is shown that the phase margin of DOB controller remains quite a large value even though the time constant of Q-filter becomes smaller. The computer simulation results show that DOB controller is able to stabilize the motor system even in the presence of unmodeled dynamics. On the contrary, the unity-feedback system fails to maintain stability when a high gain feedback is employed for the purpose of achieving better disturbance attenuation performance.

Smart passive control of buildings with higher redundancy and robustness using base-isolation and inter-connection

  • Murase, Mitsuru;Tsuji, Masaaki;Takewaki, Izuru
    • Earthquakes and Structures
    • /
    • v.4 no.6
    • /
    • pp.649-670
    • /
    • 2013
  • It is known that a base-isolated building exhibits a large response to a long-duration, long-period wave and an inter-connected system without base-isolation shows a large response to a pulse-type wave. To compensate for each deficiency, a new hybrid passive control system is investigated in which a base-isolated building is connected to another building (free wall) with oil dampers. It is demonstrated that the present hybrid passive control system is effective both for pulse-type ground motions and long-duration and long-period ground motions and has high redundancy and robustness for a broad range of disturbances.

Secure Object Detection Based on Deep Learning

  • Kim, Keonhyeong;Jung, Im Young
    • Journal of Information Processing Systems
    • /
    • v.17 no.3
    • /
    • pp.571-585
    • /
    • 2021
  • Applications for object detection are expanding as it is automated through artificial intelligence-based processing, such as deep learning, on a large volume of images and videos. High dependence on training data and a non-transparent way to find answers are the common characteristics of deep learning. Attacks on training data and training models have emerged, which are closely related to the nature of deep learning. Privacy, integrity, and robustness for the extracted information are important security issues because deep learning enables object recognition in images and videos. This paper summarizes the security issues that need to be addressed for future applications and analyzes the state-of-the-art security studies related to robustness, privacy, and integrity of object detection for images and videos.