• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.581-584
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• 2004

High ductile fiber reinforced mortar suitable for wet-mix shotcreting (sprayable ductile mortar) 10 the fresh state, while maintaining tensile strain-hardening behavior in the hardened state, has been developed based on micromechanics and workability control. In the development concept of sprayable ductile mortar, micromechanics is adopted to properly select the matrix, fiber, and interface properties to exhibit strain hardening and multiple cracking behaviors in the composites. Within the pre-determined micromechanical constraints, the workability is controlled by optimizing mix proportions. A series of spray tests show the excellent pumpability and sprayability of the sprayable ductile mortar. Subsequent direct tensile tests demonstrate that the tensile performance of sprayed mortar is comparable to that of cast mortar, for the same mix design.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.602-605
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• 1999

We dried emitting layer of EL device at 30, 80, I20 and $150^{\circ}C$ for Ihr to investigate the effects to the emission characteristics of devices. PL intensity of P3HT thin film decreased with increasing the drying temperature. But, the EL intensity and stability of device with emitting layer dried at $150^{\circ}C$ were the best. We think it s because of absence of water and remaining solvent in P3HT emitting layer. So, We suggest that the drying temperature of emitting layer of EL device should be select slightly low temperature than its glass transition temperature.

• Computers and Concrete
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• v.11 no.3
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• pp.183-199
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• 2013

To select a most desired mix proportion that meets required performances according to the quality of recycled aggregate, a large number of experimental works must be carried out. This paper proposed a new design method for the mix proportion of recycled aggregate concrete to reduce the number of trial mixes. Genetic algorithm is adapted for the method, which has been an optimization technique to solve the multi-criteria problem through the simulated biological evolutionary process. Fitness functions for the required properties of concrete such as slump, density, strength, elastic modulus, carbonation resistance, price and carbon dioxide emission were developed based on statistical analysis on conventional data or adapted from various early studies. Then these fitness functions were applied in the genetic algorithm. As a result, several optimum mix proportions for recycled aggregate concrete that meets required performances were obtained.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.288-291
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• 2001

It is very important to select suspension solution for forming electrophoretic deposited YBCO thick film, because it is heavily affected to its superconducting properties. In this paper, high-temperature superconductor films of YBa$_2$Cu$_3$$O_{7-x}$ were fabricated by electrophoretic deposition (EPD) from alcohol-based suspension such as iso-propanol, iso-butanol, and their mixture. For the formation of YBCO dense and adherent coating on a silver wire by EPD, 1% PEG(1000) 2 $m\ell$, as a additive for making their surface crack-free, was used for electrophoresis. As a results, the cracks were considerably decreased and the superconducting critical current density (J$_{c}$) without/with PEG was 1200 A/$\textrm{cm}^2$ and 2020 A/$\textrm{cm}^2$, which films deposited in mix ism-propanol and iso-butanol suspension.ion.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1999.06a
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• pp.69-76
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• 1999

This paper proposes a new region-oriented coding scheme of still images. The scheme first segments an image into homogeneous regions by making use of Voronoi diagrams. Then luminance components in each Voronoi region are encoded using a transform coding technique which employs the Schmidt's orthogonalization method to produce orthonormal basis-functions for arbitrarily shaped regions. In this technique, coding efficiency depends on the properties of initial vectors to be orthogonalized. Therefore we adaptively select a set of initial vectors as well as the order in which these vectors are orthogonalized. Simulation results indicate that the proposed coding scheme achieves higher coding performance with much less computation than the KLT-based scheme which we reported formerly.

• Journal of Biomedical Engineering Research
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• v.15 no.2
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• pp.201-208
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• 1994

Many three-dimensional object modeling and display methods for computer graphics and computer vision have been developed. Recently, with the help of medical imaging devices such as computerized tomography, magnetic resonance image, etc., some of those object modeling and display methods have been widely used for capturing the shape, structure and other properties of real objects in many medical applications. In this paper, we propose the reconstruction and display method of the three-dimensional object from a series of the cross sectonal image. It is implemented by using the automatic threshold selection method and the contour following algorithm. The combination of curvature and distance, we select feature points. Those feature points are the candidates for the tiling method. As a results, it is proven that this proposed method is very effective and useful in the comprehension of the object's structure. Without the technician's responce, it can be automated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.93-94
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• 2005

Cu metallization using electrochemical plating(ECP) has played an important role in back end of line(BEOL) interconnect formation. In this work, we studied the optimized copper thickness using Bottom-up Gap-fill in Cu ECP, which is closely related with the pattern dependencies in Cu ECP and Cu dual damascene process at 0.13 ${\mu}m$ technology node. In order to select an optimized Cu ECP thickness, we examined Cu ECP bulge, Cu CMP dishing and electrical properties of via hole and line trench over dual damascene patterned wafers split into different ECP Cu thickness.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.105-106
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• 2018

It is important to set up a reasonable failure criterion for cladding, because being able to determine the cladding integrity during transportation is essential for the evaluation of SNF transportation system. There are a few of measures which can be used as a failure criterion for cladding subjected to its specific failure mode. Therefore, to select and to use appropriate failure criterion measures, i.e. strain(UE), $K_{IC}$, and CSED would be a key in evaluating the cladding integrity during transportation with every aspects. In order to justify and quantify that criterion properly, various experiments for the mechanical properties of the claddings with different conditions shall be implemented, which data will enable to justify the failure criteria proposed.

• ETRI Journal
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• v.43 no.3
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• pp.561-570
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• 2021

This paper presents master key identifier based protocol steganography (MKIPS), a new approach toward creating a covert channel within the Secure Real-time Transfer Protocol, also known as SRTP. This can be achieved using the ability of the sender of Voice-over-Internet Protocol packets to select a master key from a pre-shared list of available cryptographic keys. This list is handed to the SRTP sender and receiver by an external key management protocol during session initiation. In this work, by intelligent utilization of the master key identifier field in the SRTP packet creation process, a covert channel is created. The proposed covert channel can reach a relatively high transfer rate, and its capacity may vary based on the underlying SRTP channel properties. In comparison to existing data embedding methods in SRTP, MKIPS can convey a secret message without adding to the traffic overhead of the channel and packet loss in the destination. Additionally, the proposed covert channel is as robust as its underlying user datagram protocol channel.

• Communications for Statistical Applications and Methods
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• v.26 no.2
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• pp.149-161
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• 2019

In this article, we suggest the following approaches to simultaneous variable selection and outlier detection. First, we determine possible candidates for outliers using properties of an intercept estimator in a difference-based regression model, and the information of outliers is reflected in the multiple regression model adding mean shift parameters. Second, we select the best model from the model including the outlier candidates as predictors using stochastic search variable selection. Finally, we evaluate our method using simulations and real data analysis to yield promising results. In addition, we need to develop our method to make robust estimates. We will also to the nonparametric regression model for simultaneous outlier detection and variable selection.