• Title/Summary/Keyword: Robustness Testing

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R&D기반 성장모형의 실증분석

  • 조상섭;정동진;장송자
    • Journal of Technology Innovation
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    • v.10 no.2
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    • pp.91-105
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    • 2002
  • This paper extends the empirical analysis on R&D based growth model so that the nonstationary panel unit root testing methods can be used to distinguish the exogenous growth model and R&D based growth model for the 1981-1999 period with fourteen OECD economies including Korea. Our results show that first, using U.S. and Group mean as benchmarking, the stochastic R&D productivity convergence to benchmarking is not supported in our data set. Second, the empirical results for stochastic nonconvergence to the U.S. or group mean also are robustness to panel unit root methods. We, therefore, find strong support for the implications for R&D based growth model.

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SVD-Based Digital Image Forensics for Detecting Tampering (위변조 검출을 위한 SVD 디지털 이미지 포렌직)

  • Song, Geun-Sil;Kim, Mi-Ae;Lee, Won-Hyung
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.377-378
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    • 2006
  • The proposed method measures the correlation maps of SVD that are used to interpret data relations and structures between the original image and the distorted image. It seems that the SVD results can be used to assist us in gaining information about covariance structure of two images. This method is able to work in the complete absence of any digital watermark or signature. The effectiveness of this method is seen through testing the robustness against JPEG compression.

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Utterance Verification Using Search Confusion Rate and Its N-Best Approach

  • Kim, Kyu-Hong;Kim, Hoi-Rin;Hahn, Min-Soo
    • ETRI Journal
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    • v.27 no.4
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    • pp.461-464
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    • 2005
  • Recently, a variety of confidence measures for utterance verification has been studied to improve speech recognition performance by rejecting out-of-vocabulary inputs. Most of the conventional confidence measures for utterance verification are based primarily on hypothesis testing or an approximated posterior probability, and their performances depend on the robustness of an alternative hypothesis or the prior probability. We introduce a novel confidence measure called a search confusion rate (SCR), which does not require an alternative hypothesis or the approximation of posterior probability. Our confusion-based approach shows better performance in additive noise-corrupted speech as well as in clean speech.

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A Study on the Durability Estimation of Vehicle Fuel Tank (차량용 연료탱크의 내구도 평가에 관한 연구)

  • Hong, Min-Sung;Cho, Eun-Hee
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.18 no.6
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    • pp.614-620
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    • 2009
  • A fuel tank of a vehicle is an important part due to its flammable contents ant its importance during crash conditions. Therefore, the fuel tank's design should be assessed for durability and robustness to ensure safety during the early development phase. Previously, evaluation for the durability was done by testing in physical driving conditions which could only be done after the completion of the vehicle. Computation simulation is a more effective method to evaluate the strength and durability of the fuel tank during the early stage. In this paper, two outstanding computational simulation methods are studied. One evaluates PV cycle fatigue due to build up pressure in the fuel tank and the other evaluates the PSD vibration fatigue from modal characteristics. The results show that computational methods agree with physical tests and are thus suitable to analyze the strength and durability of the fuel tank at early development phase.

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Investigation of Strain Measurements using Digital Image Correlation with a Finite Element Method

  • Zhao, Jian;Zhao, Dong
    • Journal of the Optical Society of Korea
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    • v.17 no.5
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    • pp.399-404
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    • 2013
  • This article proposes a digital image correlation (DIC) strain measurement method based on a finite element (FE) algorithm. A two-step digital image correlation is presented. In the first step, the gradient-based subpixels technique is used to search the displacements of a region of interest of the specimen, and then the strain fields are obtained by utilizing the finite element method in the second step. Both simulation and experiment processing, including tensile strain deformation, show that the proposed method can achieve nearly the same accuracy as the cubic spline interpolation method in most cases and higher accuracy in some cases, such as the simulations of uniaxial tension with and without noise. The results show that it also has a good noise-robustness. Finally, this method is used in the uniaxial tensile testing for Dahurian Larch wood specimens with or without a hole, and the obtained strain values are close to the results which were obtained from the strain gauge and the cubic spline interpolation method.

Thermal environmental performance evaluation of 4kW power electronic cooling system for commercial vehicle (4kW급 상용차량용 전력전자 냉방장치의 열 환경 성능평가)

  • Han, Keun-Woo;Kim, Seong-Gon;Lee, Chung-Hoon;Choi, Myoung-Hyun;Jung, Young-Gook
    • Proceedings of the KIPE Conference
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    • 2017.07a
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    • pp.290-291
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    • 2017
  • This study deals with an evaluation method for testing the robustness of the 4 kW commercial power electronic cooling system to the thermal environment. The power electronic cooling system consists of a cascaded push-pull DC / DC converter, a three-phase DC / AC inverter, and an electric compressor. The system manufactured by the thermal environment evaluation test (heat distribution test, thermal impact test, high temperature operation test, temperature cycle test, low temperature operation test) for the commercial electric power cooling system for commercial vehicle proves that it is robust against thermal environment.

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Simulation of Reservoir Sediment Deposition in Low-head Dams using Artificial Neural Networks

  • Idrees, Muhammad Bilal;Sattar, Muhammad Nouman;Lee, Jin-Young;Kim, Tae-Woong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.159-159
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    • 2019
  • In this study, the simulation of sediment deposition at Sangju weir reservoir, South Korea, was carried out using artificial neural networks. The ANNs have typically been used in water resources engineering problems for their robustness and high degree of accuracy. Three basic variables namely turbid water inflow, outflow, and water stage have been used as input variables. It was found that ANNs were able to establish valid relationship between input variables and target variable of sedimentation. The R value was 0.9806, 0.9091, and 0.8758 for training, validation, and testing phase respectively. Comparative analysis was also performed to find optimum structure of ANN for sediment deposition prediction. 3-14-1 network architecture using BR algorithm outperformed all other combinations. It was concluded that ANN possess mapping capabilities for complex, non-linear phenomenon of reservoir sedimentation.

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Tilt Angle Measurement Based on Arrayed Eddy Current Sensors

  • Chao, Xuewei;Li, Yang;Nie, Jing
    • Journal of Magnetics
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    • v.21 no.4
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    • pp.524-528
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    • 2016
  • Eddy current (EC) sensor works based on the electromagnetic induction principle and has been widely applied in the industrial testing and evaluation due to its robustness and environmental adaptability. Meanwhile, tilt angle measurement is mainly based on the laser or visual method, which is strict with the measurement environment and not suitable for the industrial applications. In this paper, a novel tilt angle measurement method based on arrayed EC sensors is proposed. Both the simulation and experiments indicate that the measured error is approximately linear with tilt angle and the accuracy after compensation is $0.25^{\circ}$. In conclusion, this research cannot only broaden the scope of EC application, but also overcome the shortcomings of existing angle measurement methods.

A Variant Guillain-Barré Syndrome with Anti-Ganglioside Complex Antibody

  • Huh, So-Young;Lee, So-Young;Lee, Jin-Hyung;Lee, Won Gu;Kim, Jong Kuk;Yoon, Byeol-A;Kim, Nam Jun
    • Journal of Neurocritical Care
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    • v.11 no.2
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    • pp.134-136
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    • 2018
  • Background: Recently, anti-ganglioside complex (GSC) antibodies were discovered among the various subtypes of Guillain-$Barr{\acute{e}}$ syndrome. GSC is the novel glycoepitopes formed by two individual ganglioside molecules. Case Report: We present a 36-year-old man with overlap Miller Fisher syndrome and acute bulbar palsy who had anti-GSC antibody that provided diagnostic robustness. Conclusion: Anti-GSC testing could be considered important in patients who show atypical manifestation with negative antibody reaction against each constituent ganglioside.

Optical Design of A Compact Imaging Spectrometer for STSAT3

  • Lee, Jun-Ho;Jang, Tae-Seong;Yang, Ho-Soon;Rhee, Seung-Wu
    • Journal of the Optical Society of Korea
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    • v.12 no.4
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    • pp.262-268
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    • 2008
  • A compact imaging spectrometer (COMIS) for use in the STSAT3 microsatellite is currently under development. It is scheduled to be launched into a low Sun-synchronous Earth orbit (${\sim}700km$) by the end of 2010. COMIS was inspired by the success of CHRIS, which is a small hyperspectral imager developed for the ESA microsatellite PROBA. COMIS is designed to achieve nearly equivalent imaging capabilities of CHRIS in a smaller (65 mm diameter and 4.3 kg mass) and mechanically superior (in terms of alignment and robustness) package. Its main operational goal will be the imaging of Earth's surface and atmosphere with ground sampling distances of ${\sim}30m$ at the $18{\sim}62$ spectral bands ($4.0{\sim}1.05{\mu}m$). This imaging will be used for environmental monitoring, such as the in-land water quality monitoring of Paldang Lake, which is located next to Seoul, South Korea. The optics of COMIS consists of two parts: imaging telescope and dispersing relay optics. The imaging telescope, which operates at an f-ratio of 4.6, forms an image (of Earth's surface or atmosphere) onto an intermediate image plane. The dispersion relay optics disperses the image and relay it onto a CCD plane. All COMIS lenses and mirrors are spherical and are made from used silica exclusively. In addition, the optics is designed such that the optical axis of the dispersed image is parallel to the optical axis of the telescope. Previous efforts focused on manufacturing ease, alignment, assembly, testing, and improved robustness in space environments.