• Title/Summary/Keyword: Modified K-Means

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Preparation of Poly(ethylene terephthalate) fibers containing Pely(hydroxy ether of bisphenol A) (Poly(hydroxy ether of bisphenol A)를 함유한 PET섬유 제조)

  • Lim, Sang Kyu;Park, Kwang Hyun;Son, Tae Won;Song, Jae Soo
    • Textile Coloration and Finishing
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    • v.9 no.2
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    • pp.17-24
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    • 1997
  • PET/PHE blends were prepared by the mixing of poly(ethylene terephthalate) and poly(hydroxyether of bisphenol A) at melt state above PET melting temperature and modified PET fibers having less than 5 wt% of PHE were also prepared by the melt spinning of the PET/PHE blends. The PET/PHE blends were able to prepare by means of physical mixing concept, except the chemical interaction between hydroxyl groups of PHE and ester groups of PET. It has been revealed that the modified PET fibers have some hydrophilic properties such as low contact angle and easy-dyeable characters.

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Utilizing Particle Swarm Optimization into Multimodal Function Optimization

  • Pham, Minh-Trien;Baatar, Nyambayar;Koh, Chang-Seop
    • Proceedings of the KIEE Conference
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    • 2008.10c
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    • pp.86-89
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    • 2008
  • There are some modified methods such as K-means Clustering Particle Swarm Optimization and Niching Particle Swarm Optimization based on PSO which aim to locate all optima in multimodal functions. K-means Clustering Particle Optimization could locate all optima of functions with finite number of optima. Niching Particle Swarm Optimization is able to locate all of optima but high computing time. Because of those disadvantages, we proposed a new method that could locate all of optima with reasonal time. We applied our method and others as well to analytic functions. By comparing the outcomes, it is shown that our method is significantly more effective than the two others.

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CT HEAD IMAGES SEGMENTATION USING UNSUPERVISED TECHNIQUES

  • Lee, Tong Hau;Fauzi, Mohammad Faizal Ahmad;Komiya, Ryoichi;Hu, Ng
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.217-222
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    • 2009
  • In this paper, a new approach is proposed for the segmentation of Computed Tomography (CT) head images. The approach consists of two-stage segmentation with each stage contains two different segmentation techniques. The ultimate aim is to segment the CT head images into three classes which are abnormalities, cerebrospinal fluid (CSF) and brain matter. For the first stage segmentation, k-means and fuzzy c-means (FCM) segmentation are implemented in order to acquire the abnormalities. Whereas for the second stage segmentation, modified FCM with population-diameter independent (PDI) and expectation-maximization (EM) segmentation are adopted to obtain the CSF and brain matter. The experimental results have demonstrated that the proposed system is feasible and achieve satisfactory results.

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Sweet Spot Search of Array Antenna Beam (Array 안테나 빔의 스위트 스폿 탐색)

  • Eom, Ki-Hwan;Kang, Seong-Ho;Lee, Chang-Young;NamKung, Wook;Hyun, Kyo-Hwan
    • 한국정보통신설비학회:학술대회논문집
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    • 2005.08a
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    • pp.115-119
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    • 2005
  • In this paper, we propose a method that search the sweet spot of array antenna beam, and keep it for fast speed transmission in millimeter wave on single array antenna link. We use TDD(Time Division Duplex) as transfer method, and it transfers the control data of antenna. The proposed method is the modified genetic algorithm which selects a superior initial group through slave-processing in order to resolve the local solution of genetic algorithm. The efficiency of the proposed method is verified by means of simulations with white Gaussian noise and not on single array antenna link.

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Efficiency to Discovery Transgenic Loci in GM Rice Using Next Generation Sequencing Whole Genome Re-sequencing

  • Park, Doori;Kim, Dongin;Jang, Green;Lim, Jongsung;Shin, Yun-Ji;Kim, Jina;Seo, Mi-Seong;Park, Su-Hyun;Kim, Ju-Kon;Kwon, Tae-Ho;Choi, Ik-Young
    • Genomics & Informatics
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    • v.13 no.3
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    • pp.81-85
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    • 2015
  • Molecular characterization technology in genetically modified organisms, in addition to how transgenic biotechnologies are developed now require full transparency to assess the risk to living modified and non-modified organisms. Next generation sequencing (NGS) methodology is suggested as an effective means in genome characterization and detection of transgenic insertion locations. In the present study, we applied NGS to insert transgenic loci, specifically the epidermal growth factor (EGF) in genetically modified rice cells. A total of 29.3 Gb (${\sim}72{\times}coverage$) was sequenced with a $2{\times}150bp$ paired end method by Illumina HiSeq2500, which was consecutively mapped to the rice genome and T-vector sequence. The compatible pairs of reads were successfully mapped to 10 loci on the rice chromosome and vector sequences were validated to the insertion location by polymerase chain reaction (PCR) amplification. The EGF transgenic site was confirmed only on chromosome 4 by PCR. Results of this study demonstrated the success of NGS data to characterize the rice genome. Bioinformatics analyses must be developed in association with NGS data to identify highly accurate transgenic sites.

Surface Modification of Multi-walled Carbon Nanotubes for Enhancement of Dispersion and Electrochemical Properties

  • Kim, Young-Ja;Zhang, Wentao;Lee, Hong-Ro;Kim, Jong-Hyee
    • Journal of the Korean institute of surface engineering
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    • v.41 no.5
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    • pp.194-198
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    • 2008
  • Several methods for improving dispersion of carbon nanotubes (CNTs) have been investigated. CNTs modified by acids and hydrogen peroxide ($H_2O_2$) showed improved dispersion. From SEM micrographs and photos of dispersion, CNTs modified with nitric acid and $H_2O_2$, showed no agglomeration in solution even standing for 4 months, which means successfully improved dispersion property. TEM micrographs of surface modified single CNT treated with 69% $HNO_3$ in boiling acid solution as the optimum method were obtained. For confirmation of CNTs' application to EDLC electrode materials, characteristics of EDLC have been analyzed by cyclic voltammetry curve, specific capacitance of unit cell, electrode discharge curves and AC impedance curve. From the results, it could be confirmed that electrochemical properties of CNTs were enhanced after surface modification with 69% $HNO_3$ acid treatment.

Optimization Design for Dynamic Characters of Electromagnetic Apparatus Based on Niche Sorting Multi-objective Particle Swarm Algorithm

  • Xu, Le;You, Jiaxin;Yu, Haidan;Liang, Huimin
    • Journal of Magnetics
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    • v.21 no.4
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    • pp.660-665
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    • 2016
  • The electromagnetic apparatus plays an important role in high power electrical systems. It is of great importance to provide an effective approach for the optimization of the high power electromagnetic apparatus. However, premature convergence and few Pareto solution set of the optimization for electromagnetic apparatus always happen. This paper proposed a modified multi-objective particle swarm optimization algorithm based on the niche sorting strategy. Applying to the modified algorithm, this paper guarantee the better Pareto optimal front with an enhanced distribution. Aiming at shortcomings in the closing bounce and slow breaking velocity of electromagnetic apparatus, the multi-objective optimization model was established on the basis of the traditional optimization. Besides, by means of the improved multi-objective particle swarm optimization algorithm, this paper processed the model and obtained a series of optimized parameters (decision variables). Compared with other different classical algorithms, the modified algorithm has a satisfactory performance in the multi-objective optimization problems in the electromagnetic apparatus.

COMMON RAIL INJECTOR MODIFIED TO ACHIEVE A MODULATION OF THE INJECTION RATE

  • FICARELLA A.;GIUFFRIDA A.;LANZAFAME R.
    • International Journal of Automotive Technology
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    • v.6 no.4
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    • pp.305-314
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    • 2005
  • Injection rate shape control is one feature of a diesel fuel injection system that is strongly desired at this time. In the conventional common rail system, it is difficult to control the injection rate since the fuel pressure is constant during the injection period, resulting in a nearly rectangular rate shape. In order to look into possible injection modulations, injectors equipped with standard and geometrically modified control valves were investigated in detail by means of computer modelling and simulation. Experiments were carried out to validate the feasibility of such a shaping. The results of this study show a noteworthy dependence of the fuel rate on geometrical modifications in the piloting stage of the injector.

An esthetic appliance for the management of crown-root fracture: a case report

  • Jeon, Sang-Min;Lee, Kang-Hee;Jung, Bock-Young
    • Restorative Dentistry and Endodontics
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    • v.39 no.3
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    • pp.226-229
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    • 2014
  • Orthodontic extrusion is usually performed by means of a fixed orthodontic appliance that utilizes arch wire attached to adjacent teeth and transfers the desired force by elastic from the wire to the root. However, clinicians often encounter cases where the bonding required for tooth traction is not possible because the adjacent teeth have been restored with ceramic or veneer. The purpose of this case report is to describe a modified orthodontic extrusion appliance that is useful when conventional orthodontic treatment is not possible. The modified appliance was fabricated using an artificial tooth, clear plastic sheeting, and a braided fiber-reinforced composite strip that covered adjacent teeth without bonding. It satisfied the esthetic and functional needs of the patient and established the optimal biologic width.

A New Approach for SINS Stationary Self-alignment Based on IMU Measurement

  • Zhou, Jiangbin;Yuan, Jianping;Yue, Xiaokui
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.355-359
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    • 2006
  • For the poor observability of azimuth misalignment angle and east gyro drift rate of the traditional initial alignment, a bran-new SINS stationary fast self-alignment approach is proposed. By means of analyzing the characteristic of the strapdown inertial navigation system (SINS) stationary alignment seriously, the new approach takes full advantage of the specific force and angular velocity information given by inertial measurement unit (IMU) instead of the mechanization of SINS. Firstly, coarse alignment algorithm is presented. Secondly, a new fine alignment model for SINS stationary self-alignment is derived, and the observability of the model is analysed. Then, a modified Sage-Husa adaptive Kalman filter is introduced to estimate the misalignment angles. Finally, some computer simulation results illustrate the efficiency of the new approach and its advantages, such as higher alignment accuracy, shorter alignment time, more self-contained and less calculation.

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