• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.229-230
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• 2006

The global metal injection moulding industry is getting mature. The technology is on its way to grow from a niche technology to a widely accepted manufacturing process. This paper addresses the latest technological trends in MIM. Challenges in materials development as well as the current limits of the technology are discussed. Trends in processing like 2-component injection moulding and micro injection moulding are presented. The European MIM market situation is described and some key factors for business success are addressed. In the discussion of future business opportunities best practice examples are included.

• The Journal of Society for e-Business Studies
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• v.12 no.4
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• pp.17-27
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• 2007

This paper proposes a key distribution and authentication protocol between user, service provider and key distribution center (KDC). This protocol is based on symmetric cryptosystem, challenge-response, Diffie-Hellman component and hash function. In the proposed protocol, user and server update the session key under token-update operation, and user can process repeated efficient authentications by using updated session keys. And another merit is that KDC needs not to totally control the session key between user and server in proposed protocol. Even an attacker steals the parameters from the KDC, the attacker still can not calculate session key. According to the comparison and analysis with other protocols, our proposed protocol provides good efficiency and forward secure session key.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.2
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• pp.301-314
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• 2015

Aiming at accurately distinguishing modeless component and natural vibration mode terms from data series of nonlinear and non-stationary processes, such as Vortex-Induced Vibration (VIV), a new empirical mode decomposition method has been developed in this paper. The key innovation related to this technique concerns the method to decompose modeless component from non-stationary process, characterized by a predetermined 'maximum intrinsic time window' and cubic spline. The introduction of conceptual modeless component eliminates the requirement of using spurious harmonics to represent nonlinear and non-stationary signals and then makes subsequent modal identification more accurate and meaningful. It neither slacks the vibration power of natural modes nor aggrandizes spurious energy of modeless component. The scale of the maximum intrinsic time window has been well designed, avoiding energy aliasing in data processing. Finally, it has been applied to analyze data series of vortex-induced vibration processes. Taking advantage of this newly introduced empirical decomposition method and mode identification technique, the vibration analysis about vortex-induced vibration becomes more meaningful.

• Steel and Composite Structures
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• v.38 no.6
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• pp.637-656
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• 2021

The component-based method is widely used to analyze the initial stiffness of joint in steel structures. In this study, an analytical component model for determining the column face stiffness of square or rectangular hollow section (SHS/RHS) subjected to tension was established, focusing on endplate connections. Equations for calculating the stiffness of the SHS/RHS column face in bending were derived through regression analysis using numerical results obtained from a finite element model database. Because the presence of bolt holes decreased the bending stiffness of the column face, this effect was calculated using a novel plate-spring-based model through numerical analysis. The developed component model was first applied to predict the bending stiffness of the SHS column face determined through tests. Furthermore, this model was incorporated into the component-based method with other effective components, e.g., bolts under tension, to determine the tensile stiffness of the T-stub connections, which connects the SHS column, and the initial rotational stiffness of the joints. A comparison between the model predictions, test data, and numerical results confirms that the proposed model shows satisfactory accuracy in evaluating the bending stiffness of SHS column faces.

• 한국IT서비스학회:학술대회논문집
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• 2003.05a
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• pp.647-664
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• 2003

[ $\circ$ ] Enterprise architecture is essential for ROI of e-Enterprise. $\circ$ An architecture is described from business, application, data and technical views and these must be complete and consistent. $\circ$ UML-based CBD is currently the best approach to obtaining architecture-centric, flexible and interoperable systems. $\circt$ Reuse of architecture, components, shared services and app frameworks is key to achieving both quality and productivity. $\circ$ Web service, the NBT, cannot be tapped without the architecting capability. $\circ$ Architects with world-class domain as well as software engineering knowledge are key to success of Korean software industry.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.8
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• pp.2010-2026
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• 2013

The combination of biometrics and cryptography gains a lot of attention from both academic and industry community. The noisy biometric measurement makes traditional identity based cryptosystems unusable. Also the extraction of key from biometric information is difficult. In this paper, we propose an efficient biometric identity based signature scheme (Bio-IBS) that makes use of fuzzy extractor to generate the key from a biometric data of user. The component fuzzy extraction is based on error correction code. We also prove that the security of suggested scheme is reduced to computational Diffie-Hellman (CDH) assumption instead of other strong assumptions. Meanwhile, the comparison with existing schemes shows that efficiency of the system is enhanced.

• Journal of Multimedia Information System
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• v.5 no.4
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• pp.221-228
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• 2018

Skin-color information is not sufficient for palmprint segmentation in complex scenes, including mobile environments. Traditional active shape model (ASM) combines gray information and shape information, but its performance is not good in complex scenes. An improved ASM method is developed for palmprint segmentation, in which Perux method normalizes the shape of the palm. Then the shape model of the palm is calculated with principal component analysis. Finally, the color likelihood degree is used to replace the gray information for target fitting. The improved ASM method reduces the complexity, while improves the accuracy and robustness.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.10
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• pp.3989-4006
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• 2020

The intelligent agriculture monitoring is based on the perception and analysis of environmental data, which enables the monitoring of the production environment and the control of environmental regulation equipment. As the scale of the application continues to expand, a large amount of data will be generated from the perception layer and uploaded to the cloud service, which will bring challenges of insufficient bandwidth and processing capacity. A fog-based offline and real-time hybrid data analysis architecture was proposed in this paper, which combines offline and real-time analysis to enable real-time data processing on resource-constrained IoT devices. Furthermore, we propose a data process-ing algorithm based on the incremental principal component analysis, which can achieve data dimensionality reduction and update of principal components. We also introduce the concept of Squared Prediction Error (SPE) value and realize the abnormal detection of data through the combination of SPE value and data fusion algorithm. To ensure the accuracy and effectiveness of the algorithm, we design a regular-SPE hybrid model update strategy, which enables the principal component to be updated on demand when data anomalies are found. In addition, this strategy can significantly reduce resource consumption growth due to the data analysis architectures. Practical datasets-based simulations have confirmed that the proposed algorithm can perform data fusion and exception processing in real-time on resource-constrained devices; Our model update strategy can reduce the overall system resource consumption while ensuring the accuracy of the algorithm.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3213-3217
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• 2012

Reactive adsorption desulfurization (RADS) experiments were conducted over a series of commercial metal oxide supports ($Al_2O_{3-}$, $SiO_{2-}$, $TiO_{2-}$ and $ZrO_{2-}$) supported Ni/ZnO adsorbents. The adsorbents were characterized by X-ray diffraction (XRD), temperature programmed reduction (TPR), and Fourier transform infrared spectroscopy (FTIR) in order to find out the influence of specific types of surface chemistry and structural characteristics on the sulfur adsorptive capacity. The desulfurization performance of all the studied adsorbents decreased in the following order: Ni/ZnO-$TiO_2$ > Ni/ZnO-$ZrO_2$ > Ni/ZnO-$SiO_2$ > Ni/ZnO-$Al_2O_3$. Ni/ZnO-$TiO_2$ shows the best performance and the three hour sulfur capacity can achieve 12.34 mg S/g adsorbent with a WHSV of $4h^{-1}$. Various characterization techniques suggest that weak interaction between active component and support component, high dispersion of NiO and ZnO, high reducibility and large total Lewis acidity of the adsorbents are important factors in achieving better RADS performance.

• Journal of The Korean Astronomical Society
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• v.38 no.4
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• pp.463-470
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• 2005

In this paper, we have made the component-based development of observational software for KASI solar imaging spectrograph (KSIS) that is able to obtain three-dimensional imaging spectrograms by using a scanning mirror in front of the spectrograph slit. Since 2002, the KASI solar spectrograph has been successfully operated to observe solar spectra for a given slit region as well as to inspect the response functions of narrow band filters. To improve its capability, we have developed the KSIS that can perform sequential observations of solar spectra by simultaneously controlling the scanning mirror and the CCD camera via Visual C++. Main task of this paper is to introduce the development of the component-based software for KSIS. Each component of the software is reusable on the level of executable file instead of source code because the software was developed by using CBD (component-based development) methodology. The main advantage of such a component-based software is that key components such as image processing component and display component can be applied to other similar observational software without any modifications. Using this software, we have successfully obtained solar imaging spectra of an active region (AR 10708) including a small sunspot. Finally, we present solar $H{\alpha}$ spectra ($6562.81{\AA}$) that were obtained at an active region and a quiet region in order to confirm the validity of the developed KSIS and its software.