• Title/Summary/Keyword: core group

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Phylogenetic Evaluation of Stereoid Fungi

  • Yoon, Sung-Il;Kim, Seon-Young;Lim, Young-Woon;Jung, Hack-Sung
    • Journal of Microbiology and Biotechnology
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    • v.13 no.3
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    • pp.406-414
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    • 2003
  • Phylogenetic relationships of stereoid fungi were examined by comparing nuclear small subunit ribosomal RNA gene sequences. Stereoid taxa were scattered into several groups and the traditional Stereaceae proved to be polyphyletic. Srereum and Xylobolus were classified in the Stereaceae as the core group of stereoid fungi, and Amylostereum was grouped with Echinodontium of the Echinodontiaceae. Chondrostereum and Cystosrereum were clustered in the Stereaceae sensu Donk and Cymatoderma and Podoscypha in the Podoscyphaceae Reid. Columnocystis abietinum and C. ambigua were grouped with Meripilus giganteus and proved to be not included in the Chaetodermataceae sensu Nakasone. Lopharia cinerascens and L. mirabilis were grouped together but L. spadicea was unrelated to them, indicating that Lopharia is heterogeneous at a generic level.

Dislocation dynamics simulation on stability of high dense dislocation structure interacting with coarsening defects

  • Yamada, M.;Hasebe, T.;Tomita, Y.;Onizawa, T.
    • Interaction and multiscale mechanics
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    • v.1 no.4
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    • pp.437-448
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    • 2008
  • This paper examined the stability of high-dense dislocation substructures (HDDSs) associated with martensite laths in High Cr steels supposed to be used for FBR, based on a series of dislocation dynamics (DD) simulations. The DD simulations considered interactions of dislocations with impurity atoms and precipitates which substantially stabilize the structure. For simulating the dissociation processes, a point defect model is developed and implemented into a discrete DD code. Wall structure composed of high dense dislocations with and without small precipitates were artificially constructed in a simulation cell, and the stability/instability conditions of the walls were systematically investigated in the light of experimentally observed coarsening behavior of the precipitates, i.e., stress dependency of the coarsening rate and the effect of external stress. The effect of stress-dependent coarsening of the precipitates together with application of external stress on the subsequent behavior of initially stabilized dislocation structures was examined.

Studies on the Maximum Transfer Rate of Printing Ink (인쇄 잉크의 최대 전이율에 관한 연구)

  • 강상훈
    • Journal of the Korean Graphic Arts Communication Society
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    • v.13 no.1
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    • pp.1-12
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    • 1995
  • Polymeric mesogens having a regularly alternating rigid-flexible repeating structure in the main-chain polymer exhibit distinct even-odd oscillation in their thermodynamic quantities with respect to the number of methylene units in the spacer. The even-odd oscillation depends on the number of methylene groups in the spacer the entropy change at the NI(nematic-isotropic) phase transition becomes less distinct when the linking group is replaced by the carbonate. In our previous work, we have suggested that the characteristics arise from the geometrical arrangement of the linkage. In this work, we have prepared a series of carbonate-type monomer and dimer liquid crystals. The thermodynamic behaviors at the NI phase transition have been compared with those previous reported for the ether- or ester-type liquid crystals. For the dimer series, the orientational order parameter of the mesogenic core was determined by using H-NMR technique. The origin of the difference observed among linking groups was found to the geometrical characteristics of chemical structure.

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A Study on a Web-Based Student-Counseling System (웹기반 학생상담시스템에 대한 연구)

  • Hong, Soon-Chang;Han, Jae-Il
    • Journal of Information Technology Services
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    • v.4 no.1
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    • pp.141-148
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    • 2005
  • The importance of education is greatly emphasized in the IT era. However, teachers have to deal with teaching work as well as increasing non-educationalchores. One of those chores is student counseling. Nowadays, teachers have considerable difficulty in consulting students because they cannot visit their home and don't have enough information on students. Furthermore, students are not willing to participate in school counseling since they think school counseling is not of much help and is just time-consuming. Most of the current school counseling is focused on matters related to entrance into a school of higher grade such as choice of college. But, students need counseling on matters regarding their ordinary life. This paper suggests a web-based student-counseling system that may solve this problem. The paper identifies core requirements for the web-based student-counseling system, discusses its design and implementation and shows it is more effective than the current ordinary school counseling by experimenting on a group of students with this system.

Numerical simulation of unsteady propeller/rudder interaction

  • He, Lei;Kinnas, Spyros A.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.9 no.6
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    • pp.677-692
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    • 2017
  • A numerical approach based on a potential flow method is developed to simulate the unsteady interaction between propeller and rudder. In this approach, a panel method is used to solve the flow around the rudder and a vortex lattice method is used to solve the flow around the propeller, respectively. An iterative procedure is adopted to solve the interaction between propeller and rudder. The effects of one component on the other are evaluated by using induced velocities due to the other component at every time step. A fully unsteady wake alignment algorithm is implemented into the vortex lattice method to simulate the unsteady propeller flow. The Rosenhead-Moore core model is employed during the wake alignment procedure to avoid the singularities and instability. The Lamb-Oseen vortex model is adopted in the present method to decay the vortex strength around the rudder and to eliminate unrealistically high induced velocity. The present methods are applied to predict the performance of a cavitating horn-type rudder in the presence of a 6-bladed propeller. The predicted cavity patterns compare well with those observed from the experiments.

u-Manufacturing needs M2M (Machine to Machine) for Ubiquitous Computing World

  • Cha, Suk-Keun;Song, Jun-Yeob;Choi, Jin-Seok
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1112-1114
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    • 2005
  • Core position of the M2M (Machine to Machine) is device integration fusion using an emerging wireless and next internet technologies as well as IEEE 802.x, Bluetooth, Zigbee, DMB, Wibro etc. for ubiquitous environment that is complementary with IT839 strategy from Ministry of Information & Communication. This paper define and deploy about major functional requirements of M2M devices and middleware for how to it works, worldwide M2M technology trend & activities with its current & future application in manufacturing area that is called u-Manufacturing (Ubiquitous Manufacturing).

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Ultrahigh Efficiency from Novel Blue Emitters Using a Rational Molecular Design

  • Kim, Soo-Kang;Park, Young-Il;Park, Jong-Wook
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.921-924
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    • 2008
  • We investigated new deep blue emitting materials including a novel side group such as CB-203. CB-203 shows relatively 40% increased PL quantum efficiency and higher Tg of $30^{\circ}C$ compared to MADN. It exhibits high External Quantum Efficiency (EQE) of 7.18% that is two times bigger than MADN's, which is the best efficiency in case of non-doped blue fluorescence OLED device to our knowledge. And deep blue emitting materials with a new core structure (CB-301) have been synthesized. CB-301 exhibit excellent blue fluorescence properties. Undoped OLED devices using CB-301 as blue emitters was found to deep blue CIE value (0.154, 0.078) and exhibit high luminance efficiencies of 2.01cd/A at $10\;mA/cm^2$.

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Photocurrent of CdSe nanocrystals on singlewalled carbon nanotube-field effect transistor

  • Jeong, Seung-Yol;Lim, Seung-Chu;Lee, Young-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.03b
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    • pp.40-40
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    • 2010
  • CdSe nanocrystals (NCs) have been decorated on singlewalled carbon nanotubes (SWCNTs) by combining a method of chemically modified substrate along with gate-bias control. CdSe/ZnS core/shell quantum dots were negatively charged by adding mercaptoacetic acid (MAA). The silicon oxide substrate was decorated by octadecyltrichlorosilane (OTS) and converted to hydrophobic surface. The negatively charged CdSe NCs were adsorbed on the SWCNT surface by applying the negative gate bias. The selective adsorption of CdSe quantum dots on SWCNTs was confirmed by confocal laser scanning microscope. The measured photocurrent clearly demonstrates that CdSe NCs decorated SWCNT can be used for photodetector and solar cell that are operable over a wide range of wavelengths.

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Factors Influencing Strategic Use of Information Technology and Its Impact on Business Performance of SMEs

  • Kim, Moon-Koo;Jee, Kyoung-Yong
    • ETRI Journal
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    • v.29 no.4
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    • pp.497-506
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    • 2007
  • In this paper, we study the relationship between factors influencing the strategic use of IT and business performance by conducting a survey of small and medium-size enterprises (SMEs). From the results of our survey we came to several conclusions which are presented here. First, IT investment has a significant impact on the strategic use of IT, and the strategic use of IT has a significant impact on business performance. Second, SME investment in IT and strategic use of IT are influenced by both the intensity of competition in the market environment and partnership with other organizations. Third, the support from the management group in SMEs is a core factor for IT investment and strategic use of IT. Finally, for SMEs to use IT strategically and successfully, it is necessary to combine members' participation with a flexible organizational structure and culture.

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Clinical Guidelines for Hwabyung I. (Overview) (화병 임상진료지침 I. (개요))

  • Kim, Jong-Woo;Kim, Sang Young
    • Journal of Oriental Neuropsychiatry
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    • v.24 no.spc1
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    • pp.3-14
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    • 2013
  • Objectives : Hwabyung Research Center of The Korean Society Of Oriental Neuropsychiatry has attempted to develop 'Clinical Guidelines for the Treatment of Hwabyung' based on the clinical study on the theory of oriental medicine and phenomenological approach. The purpose of this guideline is to establish the basic clinical principles and improve the clinical convenience. Methods : Hwabyung Research Center constructed a committee of experts and advisory group. We extracted the core questions, collected the existing data and evaluated them. Simultaneously, we conducted studies on the major topics. Results : We selected and made suitable tools for the assessment and evaluation. We discovered evidences from clinical studies and developed the standard clinical principles. Conclusions : 'Clinical Guidelines for the Treatment of Hwabyung' is expected to be useful at the primary medical clinics of oriental medicine.