• Journal of the Korea Safety Management & Science
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• v.4 no.3
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• pp.107-122
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• 2002

There are two approaches to process control. The one is engineering process control(EPC) which is one of the techniques very widely used in the process industry and based on control theory which aims at keeping the process on target using manipulating variable. The other is statistical process control(SPC) whose main purpose is to look for assignable causes(variability) in the process. To design an integrated or combined scheme of SPC and EPC is gaining recognition in the process experiences for hybrid industry. This paper aims to investigate recent study concerned on the integration of SPC and EPC. First, we consider the difference between SPC and EPC in simple terms and review various models of EPC for integration including evaluation of previous study. Finally, we suggest some prospective research area concerned on the integration of SPC and EPC.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.4
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• pp.799-806
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• 1989

Component mode synthesis (CMS) method can be divided into free, fixed and hybrid interface method according to each component's connecting conditions. In this paper, major mode synthesis methods were reviewed and their accuracies were examined by comparing the calculated eigenvalues with those from full finite element (FE) model. Also, CMS is expanded into the coupling between finite element (FE) and experimental model. Since the assumed experimental data seldom have slope information, the slope information at the interface points is prepared by curve-fitting of the calculated values. A simple beam structure to show the effectiveness of the above method, and we found that it can improve the accuracy of the synthesis method in calculation, expecially in the low modes.

• Journal of Communications and Networks
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• v.18 no.3
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• pp.397-410
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• 2016

This paper proposes a novel cooperative localization method for distributed wireless networks in 3-dimensional (3D) global positioning system (GPS) denied environments. The proposed method, which is referred to as hybrid ellipsoidal variational algorithm (HEVA), combines the use of non-parametric belief propagation (NBP) and variational Bayes (VB) to benefit from both the use of the rich information in NBP and compact communication size of a parametric form. InHEVA, two novel filters are also employed. The first one mitigates non-line-of-sight (NLoS) time-of-arrival (ToA) messages, permitting it to work well in high noise environments with NLoS bias while the second one decreases the number of calculations. Simulation results illustrate that HEVA significantly outperforms traditional NBP methods in localization while requires only 50% of their complexity. The superiority of VB over other clustering techniques is also shown.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.383-386
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• 2005

This study proposes a case based reasoning system with two dimensional reduction techniques. In this study, vertical and horizontal dimensions of the research data are reduced through hybrid feature and instance selection process using genetic algorithms. We applied the proposed model to customer classification model which utilizes customers' demographic characteristics as inputs to predict their buying behavior for the specific product. Experimental results show that the proposed technique may improve the classification accuracy and outperform various optimized models of typical CBR system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.4C
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• pp.330-335
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• 2008

This paper proposes a packet detection algorithm for IEEE802.11n system. IEEE802.11n is a multiple input multiple output (MIMO) system and we have to consider several combining techniques which are used in multiple receive antenna system. In this paper, we propose a hybrid packet detection algorithm which combines double sliding window algorithm or delay and correlation algorithm, that is used in single input single output (SISO) system, and multiple receive antenna combining algorithms, and simulated their performances in Iin system environments and shows the results.

• Journal of Sensor Science and Technology
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• v.20 no.4
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• pp.234-237
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• 2011

This paper presents a study into pH Indicator-Embedded hydrogel micro-particles which are encoded various shapes according to the captured indicator. We incorporate various pH indicators into a photo-curable hydrogel, PEG-DA(Poly(ethylene glycol) diacrylate). Using the latest fluidic lithography techniques, we can easily fabricate variously patterned hydrogel particles based on in-situ photopolymerization of the PEG-DA in a micro-fluidic channel. The shape of the particle is related to the pH indicator inside the particle. We demonstrate that the micro pH sensors change their colors according to the pH levels. The micro pH sensors have various characteristics that are related to the curing time, particle size, etc. By changing these conditions, we can adjust the long term stability and reaction time of the hybrid micro pH sensors.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.2
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• pp.109-112
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• 2001

Androgenesis in silkworm acquires a special significance as along with combined applications of other breeding strategies like parthenogenesis and cloning, it may serve as n valuable tool for sex control in sericulture as well as selection and production of bisexual homozygous androgenetic lines. Production of hybrid silkworm yielding high proportion of male larvae is of immense use to silk industry (Strunnikov, 1975, 1983). In this review, an attempt has been made to assimilate the works carried out on androgenesis, different techniques of induction towards androgenetic development and its role in silkworm breeding.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.9
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• pp.938-945
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• 2012

To design and estimate material failures of Type III pressure vessels, which have excellent stability and performance, various modeling techniques have been introduced. This paper provided a hybrid modeling technique composed of ply-based modeling for a cylinder part and laminate-base modeling technique for a dome part for enhancing modeling efficiency. The ply-based modeling technique provided accurate ply stresses directly for predicting material failure, on the other hand, additional manipulations in stress calculations, which may cause some errors, were needed for the case of the laminate-based modeling technique. The ply stresses in fiber, transverse and in-plane shear directions were compared with the corresponding material strengths to predict material failure.

• Journal of Information Processing Systems
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• v.13 no.6
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• pp.1585-1601
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• 2017

With the rapid development of computer technologies, a number of image modification methods have emerged, which have great impacts on the security of image information. Therefore, it is necessary to protect the integrity and authenticity of digital images, and digital watermarking technique consequently becomes a research hotspot. An effort is made to survey and analyze advancements of image watermarking algorithms based on singular value decomposition (SVD) in recent years. In the first part, an overview of watermarking techniques is presented and then mathematical theory of SVD is given. Besides, SVD watermarking model, features, and evaluation indexes are demonstrated. Various SVD-based watermarking algorithms, as well as hybrid watermarking algorithms based on SVD and other transforms for copyright protection, tamper detection, location, and recovery are reviewed in the last part.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.10a
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• pp.161-162
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• 2009

하이브리드 코팅장비를 이용해 WC-CO기판위에 Ti-Si-N박막을 증착 시켰다. 이 연구는 Ti-Si-N박막의 기계적 성질에 온도와 바이어스가 미치는 영향에 대해 실험을 하였다. 증착온도가 $300^{\circ}C$까진 Ti-Si-N박막의 미세경도와 탄성률은 증가했지만 증착온도가 $300{\sim}350^{\circ}C$에서는 탄성률은 감소하고 결정 성장으로 인해 미세경도는 감소하였다. 기판 바이어스는 박막과 미세구조에 압축 잔류 응력을 야기 시킨다. 그러나 기판바이어스가 -400V 이상에서는 re-sputtering에 의해 Si함량이 감소한다. Ti-Si-N 박막의 가장 우수한 기계적 성질은 $300^{\circ}C$, -100V에서 얻을 수 있었다.