• Title/Summary/Keyword: synthesis method

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A Method to Minimize Classification Rules Based on Data Mining and Logic Synthesis

  • Kim, Jong-Wan
    • Journal of Korea Multimedia Society
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    • v.11 no.12
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    • pp.1739-1748
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    • 2008
  • When we conduct a data mining procedure on sample data sources, several rules are generated. But some rules are redundant or logically disjoint and therefore they can be removed. We suggest a new rule minimization algorithm inspired from logic synthesis to improve comprehensibility and eliminate redundant rules. The method can merge several relevant rules into one based on data mining and logic synthesis without high loss of accuracy. In case of two or more rules are candidates to be merged, we merge the rules with the attribute having the lowest information gain. To show the proposed method could be a reasonable solution, we applied the proposed approach to a problem domain constructing user preferred ontology in anti-spam systems.

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Model Establishment of a Deployable Missile Control Fin Using Substructure Synthesis Method (부구조물 합성법을 이용한 접는 미사일 조종날개 모델 수립)

  • Kim, Dae-Kwan;Bae, Jae-Sung;Lee, In;Han, Jae-Hung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.15 no.7 s.100
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    • pp.813-820
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    • 2005
  • A deployable missile control fin has some structural nonlinearities because of the worn or loose hinges and the manufacturing tolerance. The structural nonlinearity cannot be eliminated completely, and exerts significant effects on the static and dynamic characteristics of the control fin. Thus, It is important to establish the accurate deployable missile control fin model. In the present study, the nonlinear dynamic model of 4he deployable missile control fin is developed using a substructure synthesis method. The deployable missile control fin can be subdivided Into two substructures represented by linear dynamic models and a nonlinear hinge with structural nonlinearities. The nonlinear hinge model is established by using a system identification method, and the substructure modes are improved using the Frequency Response Method. A substructure synthesis method Is expanded to couple the substructure models and the nonlinear hinge model, and the nonlinear dynamic model of the fin is developed. Finally, the established nonlinear dynamic model of the deployable missile control fin is verified by dynamic tests. The established model is In good agreement with test results, showing that the present approach is useful in aeroelastic stability analyses such as time-domain nonlinear flutter analysis.

Recent Developments in Synthesis of Colloidal Quantum Dots (콜로이드 양자점 합성의 다양한 연구 개발 동향)

  • Jung, Jae-Yong;Hong, Jong-Pal;Kim, Young-Kuk
    • Journal of Powder Materials
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    • v.25 no.4
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    • pp.346-354
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    • 2018
  • Over the last decade, the study of the synthesis of semiconductor colloidal quantum dots has progressed at a tremendous rate. Colloidal quantum dots, which possess unique spectral-luminescent characteristics, are of great interest in the development of novel materials and devices, which are promising for use in various fields. Several studies have been carried out on hot injection synthesis methods. However, these methods have been found to be unsuitable for large-capacity synthesis. Therefore, this review paper introduces synthesis methods other than the hot injection synthesis method, to synthesize quantum dots with excellent optical properties, through continuous synthesis and large capacity synthesis. In addition, examples of the application of synthesized colloid quantum dots in displays, solar cells, and bio industries are provided.

Trends on Synthesis of Cu Nanoparticles by a Wet Reduction Method (습식 환원법에 의한 Cu 나노입자의 합성 동향)

  • Shin, Yong Moo;Chee, Sang-Soo;Lee, Jong-Hyun
    • Journal of the Microelectronics and Packaging Society
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    • v.20 no.3
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    • pp.11-18
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    • 2013
  • Interest in copper nanoparticles has increased as an alternative for substituting silver nanoparticles because of its lower cost and less electromigration effect than silver. In this paper, the recent research trends and main results in wet-chemical synthesis of sub-100 nm Cu nanoparticles were summarized. The characteristics of synthesis were discussed with a classification such as modified polyol synthesis, modified hydrothermal synthesis, solvothermal synthesis, and the others, focussing on effects of capping agents, reductants, and pH. Information on the oxidation of synthesized copper nanoparticles were additionally commented.

Effect of 3-Aminobenzamide on DNA Repair Synthesis and Chromosome Aberrations Induced by Mutagens in Synchronized Mammalian Cells (동시화된 포유동물세포에서 돌연변이원에 의해 유발된 DNA 회복합성 및 염색체이상에 미치는 3-Aminobenzamide의 영향)

  • 신은주;강인영;엄경일
    • Environmental Mutagens and Carcinogens
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    • v.11 no.2
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    • pp.107-117
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    • 1991
  • The effect of 3-aminobenzamide (3AB), an inhibitor of poly (ADP-ribose) polymerase, on ethyl methanesulfonate (EMS)-or bleomycin (BLM)-induced DNA repair synthesis and chromosome aberrations was examined during the cell cycle of Chinese hamster ovary (CHO)-K$_1$ cells. The synchronized cells were obtained by using thymidine double block method and mitotic selection method. Three assays were employed in this study: unscheduled DNA synthesis, alkaline elution and chromosome aberrations. 3AB alone did not induce DNA repair and chromosome aberrations in all phases. The post-treatment with 3AB inhibited DNA repair synthesis induced by EMS or BLM in G$_2$ phase, whereas 3AB did not affect chromosome aberrations induced by EMS or BLM in all phases. These results suggest that 3AB aggravates the cell cycle disturbance which occur after DNA damage, and leads to an accumulation of cells at G$_2$ phase, and inhibits DNA repair synthesis, while the effect 3AB on chromosome aberrations may need reevaluated.

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Bio-Inspired Green Nanoparticles: Synthesis, Mechanism, and Antibacterial Application

  • Velusamy, Palaniyandi;Kumar, Govindarajan Venkat;Jeyanthi, Venkadapathi;Das, Jayabrata;Pachaiappan, Raman
    • Toxicological Research
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    • v.32 no.2
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    • pp.95-102
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    • 2016
  • In the recent years, noble nanoparticles have attracted and emerged in the field of biology, medicine and electronics due to their incredible applications. There were several methods have been used for synthesis of nanoparticles such as toxic chemicals and high energy physical procedures. To overcome these, biological method has been used for the synthesis of various metal nanoparticles. Among the nanoparticles, silver nanoparticles (AgNPs) have received much attention in various fields, such as antimicrobial activity, therapeutics, bio-molecular detection, silver nanocoated medical devices and optical receptor. Moreover, the biological approach, in particular the usage of natural organisms has offered a reliable, simple, nontoxic and environmental friendly method. Hence, the current article is focused on the biological synthesis of silver nanoparticles and their application in the biomedical field.

Synthesis of $PbLaTiO_{3}$: Mn powders by hydrothermal method

  • Park, Sun-Min
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.13 no.2
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    • pp.63-67
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    • 2003
  • Synthesis of $PbLaTiO_{3}$ : Mn powders containing La and Mn was carried out using $PbO,\;TiO_{2},\;La_{2}O_{3}\;and\;MnO_{2}$ as starting materials by hydrothermal method. In the synthesis of single phase $PbLaTiO_{3}$ : Mn powder containing La and Mn, the optimal x value corresponding to La substitution was 0.01 which corresponds to $0.99(Pb_{1-x}La_{2x/3}TiO_{3})+0.01MnO_{2}$. The optimal conditions for the preparation of the powder synthesis were 8 M-KOH solvent of hydrothermal solvent, $270^{\circ}C$ of reaction temperature and 24 hrs of run time. It was found that the synthesized powders had spherical morphology with average particle size of 70 nm and specific surface area of $5.5\;m^{2}/g$.

A Study on the Text-to-Speech Conversion Using the Formant Synthesis Method (포만트 합성방식을 이용한 문자-음성 변환에 관한 연구)

  • Choi, Jin-San;Kim, Yin-Nyun;See, Jeong-Wook;Bae, Geun-Sune
    • Speech Sciences
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    • v.2
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    • pp.9-23
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    • 1997
  • Through iterative analysis and synthesis experiments on Korean monosyllables, the Korean text-to-speech system was implemented using the phoneme-based formant synthesis method. Since the formants of initial and final consonants in this system showed many variations depending on the medial vowels, the database for each phoneme was made up of formants depending on the medial vowels as well as duration information of transition region. These techniques were needed to improve the intelligibility of synthetic speech. This paper investigates also methods of concatenating the synthesis units to improve the quality of synthetic speech.

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Synthesis of Multiferroic Nanocomposites by a Polyol Method

  • Shim, In-Bo;Pyun, Jeffrey;Park, Yong-Wook;Uhm, Young-Rang;Kim, Chul-Sung
    • Journal of Powder Materials
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    • v.14 no.3 s.62
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    • pp.180-184
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    • 2007
  • The material design and synthesis are of important to modem science and technology. Here, we report the synthesis of multifunctional nanomaterials with different properties: feroelecties $YMnO_3$ and multiferroic materials such as $CoFe_2O_4-YMnO_3,\;Fe_3O_4-YMnO_3,\;CoFe_2O_4-Cd_{0.85}Zn_{0.15}S,\;and\;Fe_3O_4-Cd_{0.85}Zn_{0.15}S$ nano-composites by using a chemical synthesis process. These results provide a simple and convenient synthesis process to produce multifunctional nanocomposites.

An accurate substructural synthesis approach to random responses

  • Ying, Z.G.;Zhu, W.Q.;Ye, S.Q.;Ni, Y.Q.
    • Structural Engineering and Mechanics
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    • v.39 no.1
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    • pp.47-75
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    • 2011
  • An accurate substructural synthesis method including random responses synthesis, frequency-response functions synthesis and mid-order modes synthesis is developed based on rigorous substructure description, dynamic condensation and coupling. An entire structure can firstly be divided into several substructures according to different functions, geometric and dynamic characteristics. Substructural displacements are expressed exactly by retained mid-order fixed-interfacial normal modes and residual constraint modes. Substructural interfacial degree-of-freedoms are eliminated by interfacial displacements compatibility and forces equilibrium between adjacent substructures. Then substructural mode vibration equations are coupled to form an exact-condensed synthesized structure equation, from which structural mid-order modes are calculated accurately. Furthermore, substructural frequency-response function equations are coupled to yield an exact-condensed synthesized structure vibration equation in frequency domain, from which the generalized structural frequency-response functions are obtained. Substructural frequency-response functions are calculated separately by using the generalized frequency-response functions, which can be assembled into an entire-structural frequency-response function matrix. Substructural power spectral density functions are expressed by the exact-synthesized substructural frequency-response functions, and substructural random responses such as correlation functions and mean-square responses can be calculated separately. The accuracy and capacity of the proposed substructure synthesis method is verified by numerical examples.