• Composites Research
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• v.30 no.4
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• pp.247-253
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• 2017

In this study, the mechanical behavior and interface properties of boron nitride nanotube-poly(methyl methacrylate) nanocomposites are predicted using the molecular dynamics simulations and the double inclusion model. After modeling nanocomposite unit cell embedding single-walled nanotube and polymer, the stiffness matrix is determined from uniaxial tension and shear tests. Through the orientation average of the transversely isotropic stiffness matrix, the effective isotropic elastic constants of randomly dispersed microstructure of nanocomposites. Compared with the double inclusion model solution with a perfect interfacial condition, it is found that the interface between boron nitride nanotube and polymer matrix is weak in nature. To characterize the interphase surrounding the nanotube, the two step domain decomposition method incorporating a linear spring model at the interface is adopted. As a result, various combinations of the interfacial compliance and the interphase elastic constants are successfully determined from an inverse analysis.

• Membrane Journal
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• v.13 no.4
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• pp.268-282
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• 2003

Pervaporation-facilitated esterification with slow reaction regime was characterized by using a practical model based on non-perfect separation through membrane. A non-perfect separation in which the membrane is not perfectly permselective to water was applied to the model. Thus, membrane selectivity and membrane capability to remove water were included in the simulation model to explain how they influence the membrane-facilitated reaction process and improve the reactor performance. It was shown by simulation that in the reaction systems with non-perfect separation, reaction completion can hardly be achievable when any reactant at initial molar ratio=1 or the less abundant reactant at initial molar ratio>1 permeates through membrane, and the permeation of ester accelerates the forward reaction md increase reaction conversion at any instant through removal of product species like water. The volume change causes concentrating both reactants and products that affect the reaction with time in opposite ways; reactant-concentrating effect is dominant during the initial stage of reaction, increasing the reaction rate, and then concentrating product influences more reaction by decreasing the reaction rate.

• Korean journal of applied entomology
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• v.30 no.2
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• pp.106-110
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• 1991

The mode of inheritance of resistance to fenvalerate in the diamondback moth (Plutella xylostella L.) was studied using insecticide susceptibility and mixed function oxidase tests. Tehre were no differences in the concentration-mortality relationships between $F_1$ progenies $(S_{female}\timesR_{male},\;R_{female}\timesS_{male})$ obtained from reciprocal crosses with the susceptible and fenvalerate-selected strains(R), indicating the absence of sex-linked inheritance. Degree of dominance of the $F_1$ progenies $(S_{female}\timesR_{male},\;R_{female}\timesS_{male})$ were -0.50 and -0.46, respectively, in the insecticide susceptibility test and -0.85 and -0.81, respectively, in the mixed function oxidase test. These results suggest that inheritance of fenvalerate resistance is controlled by and incompletely recessive autosomal gene.

• Journal of Environmental Policy
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• v.14 no.4
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• pp.63-101
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• 2015

Banking and borrowing under the ETS may affect the low carbon technology investment level. If the indirect implementation measures are allowed, firms can gradually adjust their carbon reduction costs between implementation periods based on their carbon reduction costs and emission price forecasts. This implies that banking and borrowing may reduce or increase the level of low carbon technology R&D investment. In an oligopoly market, the effects of the measures are quite different from the ones in a perfectly competitive market. This is because the indirect implementation measures can shift market competition in Cournot competition model. The effects of banking and borrowing on the carbon reduction R&D investments depend on emission reduction costs, marginal production costs, discount rate, initial free allocation, and the cost reduction effects of R&D investment.

• Korean Journal of Construction Engineering and Management
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• v.2 no.4 s.8
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• pp.69-79
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• 2001

Characteristics of Contactor's Defect Liability was too many discussed. But it's not clearly defined yet. Because recent Government Construction Projects are very complex and executed through long time, too many conflicts were appeared related to Contactor's Defect Liability. Therefore to analyse and to resolve the conflicts legal aspects of Contactor's Defect Liability stated in Civil Law and Government Contract Act was systematically compared. The result of this research is as follows : (1) Characteristic of Contactor's Defect must be regarded as a breach of Contract and be an incomplete contract implementation. (2) To decide the range of Damage, Characteristic of Defect must be regarded. (3) Contactor's Defect Liability must be effectual from the day of delivery. (4) Retainage must be added to secure the completion during the Contract Period and Defect Repairing Liability must be omitted in the Contract performance Security.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.6
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• pp.11-30
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• 2019

Smartcards are used as the basic data for utilizing the various transportation policies and evaluations, etc. and provided the transportation basic statistics index. However, the main problem of the smartcard data is that the most of users do not take the alighting tag at the stop, so there is a limit to the scope of use for the total O-D trip data because incomplete O-D traffic data of transportation card users. In this study, a decision tree of learning model is estimated for the alighting stop of smartcard users. The model estimation accuracy in range less than 2 stops interval was 89.7% on average. By eliminating the incompleteness alighting stop of smartcard data through this model, it is expected to be used as the basic data for various transportation analyses and evaluations.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.1
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• pp.53-62
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• 2010

This paper introduces a classification algorithm which can be applied to a learning problem with incomplete data sets, missing variable values or a class value. This algorithm uses a data expansion method which utilizes weighted values and probability techniques. It operates by extending a classifier which are considered to be in the optimal projection plane based on Fisher's formula. To do this, some equations are derived from the procedure to be applied to the data expansion. To evaluate the performance of the proposed algorithm, results of different measurements are iteratively compared by choosing one variable in the data set and then modifying the rate of missing and non-missing values in this selected variable. And objective evaluation of data sets can be achieved by comparing, the result of a data set with non-missing variable with that of C4.5 which is a known knowledge acquisition tool in machine learning.

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.527-533
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• 2008

본 연구는 기존 RPG에서 주요한 재미 요소로 기능하던 성장 모티프가 MMORPG(Massive Multi-user Online Role Palying Game)에서 어떤 식으로 변형되어 나타나는 지 살펴본다. 성장과 역할 수행을 통해 재미를 얻는 게임인 MMORPG는 성장 서사에서 많이 나타나는 구조인 여정형 혹은 탐색형의 구조를 보편적으로 차용하고 있다. 그러나 기존 서사물에서 성장 모티프가 정체성 찾기와 같은 내면적인 변화를 나타내기 위해 구조를 차용하는 반면, 게임에서는 위의 구조를 통해 얻은 성장의 결과물을 수치의 증가나 외적 형태의 변화를 통해 나타낸다. 즉, 경험치나 아이템을 통해 성장이 수치화되어 나타나는 것이다. 이는 여정형 탐색담이라는 성장 서사의 보편적 구조에서 게임적인 특수성이 더해진 것이라 할 수 있다. 성장 소설만의 서사적 유형이란 바로 주인공의 변화 양상이 미숙에서 성숙으로, 불완전에서 완전으로, 결핍에서 충족으로 변화하는 과정을 담고 있는 이야기적 특질을 의미한다. 그러한 미숙하고 불완전한 존재가 변화하게 되는 계기와 과정, 그리고 그 결과로 구조화된 유형적 특질을 갖고 있는 소설 양식이 성장소설이라 할 수 있는 것이다. 이러한 구조화된 유형적 특질은 신화나 민담에서는 탐색담이나 여행담으로 나타난다. 게임에서의 성장은 캐릭터의 성장과 직결된다. 본격적으로 플레이어와 동일시되어 성장을 대리 경험적으로 체험하는 것은 D&D 온라인을 거쳐, 현재 MMORPG의 형태를 구현해낸 울티마 온라인이 이후부터이다. 세부적으로 구현된 세계와 온라인을 통해 생성된 방대한 네트워크 안에서 플레이어는 자신과 동일화된 캐릭터를 플레이하면서 대리경험을 하게 된다. 즉, 플레이어가 캐릭터의 성장에 작용하는 여러 가지 변수를 선택하고, 조작해가면서 자신만의 캐릭터를 생성해 나가면서, MMORPG가 구현하는 게임 세계에 구성원이자 일원이 되는 것이다. MORPG는 기존의 RPG의 선형적인 성장에 비해 복합적인 양상을 보여준다. 문화에서의 성장 서사에서 일반적으로 발견되는 여정형의 탐색담은 개발자 서사인 배경 스토리에서 나타나며, 레벨시스템과 이에 따른 공간의 배치에 따라 플레이어에게 직접적인 영향'을 끼친다. 영속적인 세계와 플레이어 간의 상호작용을 통해 일어나는 사용자 서사는 완결된 형태의 캐릭터를 무의미하게 만든다. 플레이어는 비선형적인 성장을 끊임없이 계속하게 되는 것이다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.8
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• pp.46-51
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• 2012

In this paper, we investigate the power allocation for cognitive relay networks. Cognitive relay networks offer not only increasing spectral efficiency by spectrum sharing but also extending the coverage through the use of relays. For spectrum sharing, conventional works have assumed that secondary users know perfect channel information between the secondary and primary users. However, this channel information may be outdated at the secondary user because of the time-varying properties or feedback latency from the primary user. This causes the violation for interference constraint, and the secondary user cannot share the spectrum of the primary after all. To overcome this problem, we propose the power allocation scheme for the secondary user under the allowable primary user's outage probability constraint. Since the proposed power allocation scheme does not use the instantaneous channel information, the secondary users have lower feedback burden. In addition, the proposed scheme is also robust to the outdated channel environment.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.9
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• pp.952-958
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• 2014

In this paper, we propose a parametric sparse recovery algorithm(SRA) applied to a radar signal model, based on the compressive sensing(CS), for the ISAR(Inverse Synthetic Aperture Radar) image reconstruction from an incomplete radar-cross-section(RCS) data and for the estimation of rotation rate of a target. As the SRA, the iteratively-reweighted-least-square(IRLS) is combined with the radar signal model including chirp components with unknown chirp rate in the cross-range direction. In addition, the particle swarm optimization(PSO) technique is considered for searching correct parameters related to the rotation rate. Therefore, the parametric SRA based on the IRLS can reconstruct ISAR image and estimate the rotation rate of a target efficiently, although there exists missing data in observed RCS data samples. The performance of the proposed method in terms of image entropy is also compared with that of the traditional interpolation methods for the incomplete RCS data.