• Title/Summary/Keyword: The ordered systems

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Synthesis and Characterization of Co-Surfactant Templated Mesoporous Materials with Enhanced Hydrothermal Stability

  • Kim Geon-Joong;Kim Hyun-Seok;Ko Yoon Soo;Kwon Yong Ku
    • Macromolecular Research
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    • v.13 no.6
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    • pp.499-505
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    • 2005
  • Ordered mesoporous materials with a hydrothermally-stable, protozeolitic framework were prepared by exploring the direct conversion of inorganic species based on co-surfactant templating systems. To confer hydrothermal stability on the mesoporous aterials, the organic-inorganic hybrids were heat-treated in strongly basic media. Co-surfactant templating systems of cetyltrimethylammonium bromide [$C_{16}H_{13}(CH_{3})_{3}$NBr, CTAB] with 1,3,5-trim­ethylbenzene (TMB) or a nonionic block copolymer of poly(ethylene oxide )-b-poly(propylene oxide )-b-poly(ethyl­ene oxide) ($EO_{20}PO_{70}EO_{20}$) were employed to improve the hydrothermal stability of the organic-inorganic self-assembly during the solid rearrangement process of the inorganic species. The mesoscopic ordering of the pore structure and geometry was identified by X-ray diffraction, small angle neutron scattering and electron microscopy.

Distance Estimation Using Discretized Frequency Synthesis of Ultrasound Signals (초음파의 이산 주파수 합성을 이용한 거리 측정)

  • Park, Sang-Wook;Kim, Dae-Eun
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.5
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    • pp.499-504
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    • 2011
  • In this paper, we suggest a method for discretized frequency modulations of ultrasonic signals. A continuous sweep of frequency modulation signals can be modelled with fine levels of discretization. If the ultrasound signals are modulated with monotonically decreasing frequencies, then the cross-correlation between an emitted signal and received signal can be used to identify the distance of multiple target objects. For the discretized frequency synthesis, CF ultrasounds with different frequencies are serially ordered. The auto-correlation test with the signal shows effective results for distance estimation. The discretized frequency syntheses have better distance resolution than CF ultrasound signals and the resolution depends on the number of the combined ultrasound frequencies.

Design of Learning Fuzzy Controller by the Self-Tuning Algorithm for Equipment Systems (설비시스템을 위한 자기동조기법에 의한 학습 FUZZY 제어기 설계)

  • Lee, Seung
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.9 no.6
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    • pp.71-77
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    • 1995
  • This paper deals with design method of learning fuzzy controller for control of an unknown nonlinear plant using the self-tuning algorithm of fuzzy inference rules. In this method the fuzzy identification model obtained that the joined identification model of nonlinear part and linear identification model of linear part by fuzzy inference systems. This fuzzy identification model ordered self-tuning by Decent method so as to be servile to nonlinear plant. A the end, designed learning fuzzy controller of fuzzy identification model have learning structure to model reference adaptive system. The simulation results show that th suggested identification and learning control schemes are practically feasible and effective.

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Simulation of a CIM Workflow System Using Parallel Virtual Machine (PVM)

  • Chang-Ouk Kim
    • Journal of the Korea Society for Simulation
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    • v.5 no.2
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    • pp.13-24
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    • 1996
  • Workflow is an ordered sequence of interdependent component data activities each of which can be executed on an integrated information system by accessing a remote information system. In our previous research [4], we proposed a distributed CIM Workflow system which consists of a workflow execution model called DAF-Net and an agent-based information systems called AIMIS. Given a component data activity, there needs an interaction protocol among agents which allocates the component data activity to a relevant information systems exist. The objective of this research is to propose and test two protocols: ARR(Asynchronous Request and Response)protocol and NCL(Negotiation with Case based Learning) protocol. To test the effectiveness of the protocols, we applied the PVM(Parallel Virtual Machine) software to simulate the distributed CIM Workflow system. PVM provides a distributed computing environment in which users can run different software processes in different computers while allowing communication among the processes.

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Photoresponsive Nanocontainers with Ordered Porous Channels

  • Cho, Wansu;Kwon, Youngje;Park, Chiyoung
    • Elastomers and Composites
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    • v.54 no.2
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    • pp.149-155
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    • 2019
  • Controlled mass transport in response to stimuli is essential for drug carriers. The complexity of the signaling system under physiological conditions has led researchers to develop precise nanocontainers that respond to stimuli in the physiological environment. Owing to several reasons, soft nanocontainers such as liposomes and micelles have been investigated for use as drug delivery systems. However, such carriers often suffer from the undesired leakage of drug molecules. In contrast, inorganic nanocontainers are robust, and their surfaces can be easily functionalized. For example, mesoporous silica nanoparticles equipped with gatekeeper molecules are increasingly being used for the controlled release of drug molecules in response to the desired stimuli. Since the development of the first hybrid nanocontainer comprising molecular machines, multiple versions of such gatekeeper systems featuring significantly improved stability and precise response to stimuli have been reported. In this study, various methods for incorporating photoresponsive nanocontainers with porous channels are developed.

An approach based on the LOWHM and induced LOWHM operators to group decision making under linguistic information

  • Park, Jin-Han;Lee, Bu-Young;Son, Mi-Jung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.20 no.2
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    • pp.285-291
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    • 2010
  • In this paper, we propose an induced linguistic ordered weighted harmonic mean(ILOWHM) operator. The ILOWHM operator is more general type of aggregation operator, which is based on the LHM and LOWHM operators. Based on the LOWHM and ILOWHM operator, we develop an approach to group decision making with linguistic preference relations. Finally, an application of the approach to group decision making problem with linguistic preference relations is pointed out.

Self-assembly of Si-containing block copolymers for next-generation nanofabrication

  • Jeong, Yeon-Sik
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.22-23
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    • 2011
  • As device dimensions shrink, it is increasingly important to develop fabrication methods that can create sub-15 nm features of regular or arbitrary geometry in a rapid, parallel, and efficient process. This talk will discuss approaches based on self-assembling hybrid polymers containing Si. The thin films of those materials systems can generate well-ordered periodic arrays of dots or lines. For achieving, long-range ordering, it is helpful to use lithographically-defined templates, which are in general much larger than the length-scale of self-assembled nanostructures. For example, the self-assembly of polymer nanostructures can easily be templated using an array of nanoscale topographical elements that act as guiding templates or surrogates for one of two microdomains. The solvent-vapor-induced tunability of pattern dimension and morphology will be discussed as well. Those material systems can excellently serve for high-precision self-assembly that can provide good resolution, reliability, and controllability and be considered as an option for a future nanomanufacturing technology.

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A Sequencing Problem with Fuzzy Preference Relation and its Genetic Algorithm-based Solution (퍼지선호관계 순서화 문제와 유전자 알고리즘 기반 해법)

  • Lee, Keon-Myung;Sohn, Bong-Ki
    • Journal of the Korean Institute of Intelligent Systems
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    • v.14 no.1
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    • pp.69-74
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    • 2004
  • A sequencing problem is to find an ordered sequence of some entities which maximizes (or minimize) the domain specific objective function. As some typical examples of sequencing problems, there are traveling salesman problem, job shop scheduling, flow shop scheduling, and so on. This paper introduces a new type of sequencing problems, named a sequencing problem with fuzzy preference relation, where a fuzzy preference relation is provided for the evaluation of the quality of sequences. It presents how such a problem can be formulated in terms of objective function. It also proposes a genetic algorithm applicable to such a sequencing problem.

Spatial Multiplexing Receivers in UWB MIMO Systems based on Prerake Combining

  • An, Jin-Young;Kim, Sang-Choon
    • Journal of information and communication convergence engineering
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    • v.9 no.4
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    • pp.385-390
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    • 2011
  • In this paper, various ultra-wideband (UWB) spatial multiplxing (SM) multiple input multiple output (MIMO) receivers based on a prerake diversity combining scheme are discussed and their performance is analyzed. Several UWB MIMO detection approaches such as zero forcing (ZF), minimum mean square error (MMSE), ordered successive interference cancellation (OSIC), sorted QR decomposition (SQRD), and maximum likelihood (ML) are considered in order to cope with inter-channel interference. The UWB SM systems based on transmitter-side multipath preprocessing and receiver-side MIMO detection can either boost the transmission data rate or offer significant diversity gain and improved BER performance. The error performance and complexity of linear and nonlinear detection algorithms are comparatively studied on a lognormal multipath fading channel.

A Design Techniques of the Multiple-Valued Combinational Logic Functions Using the Output Value Array Graphs (OVAG를 이용한 다치조합논리함수의 설계 기법)

  • 윤병희;김흥수
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 1999.05a
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    • pp.75-79
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    • 1999
  • 다치결정도(Multiple-valued Decision Diagram : MDD)와 순서화된 다치결정도(Ordered MDD : OMDD)는 다치논리함수의 표현에 폭넓게 사용된다. p치 n변수 인 경우 p$^{(n-1)}$ 으로 증가하는 노드의 수는 ROMDD(Reduced OMDD)를 사용하여 현저하게 감소시킬 수 있다. 그러나 다치와 다변수의 경우에는 더욱 많은 공정을 수반하게 된다. 이러한 단점을 보완하기 위해 Honghai Jiang이 제안한 2치시스템에서의 input implict/output explicit 관계를 갖는 OVAG(Output Value Array Graph)를 사용하여 다치논리함수를 표현한다. 고리고 MDD 표현이 어려운 상황에서 MOVAG(Multi OVAG)를 사용하여 보다 쉽게 출력값을 배열하는 그래프를 이끌어 낼 수 있다. 본 논문에서는 MOVAG의 구성방법과 회로에서 MOVAG로의 변환에 대한 알고리즘을 제안하였고, 알고리즘에 의한 결과를 MDD와 비교하여 노드수 감소에 따르는 처리속도가 개선됨 을 검증하였다.

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