• Wind and Structures
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• v.1 no.1
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• pp.111-125
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• 1998

This paper deals with the development of variable-node element and its application to the adaptive h-version mesh refinement-recovery for the incompressible viscous flow analysis. The element which has variable mid-side nodes can be used in generating the transition zone between the refined and unrefined element and efficiently used for the construction of a refined mesh without generating distorted elements. A modified Guassian quadrature is needed to evaluate the element matrices due to the discontinuity of derivatives of the shape functions used for the element. The penalty function method which can reduce the number of the independent variables is adopted for the purpose of computational efficiency and the selective reduced integration is carried out for the convection and pressure terms to preserve the stability of solution. For the economical analysis of transient problems in which the locations to be refined are changed in accordance with the dynamic distribution of velocity gradient, not only the mesh refinement but also the mesh recovery is needed. The numerical examples show that the optimal mesh for the finite element analysis of a wind around the structures can be obtained automatically by the proposed scheme.

• The KIPS Transactions:PartD
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• v.13D no.1 s.104
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• pp.67-74
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• 2006

The security requirements identification in the software development has received some attention recently. However, previous methods do not provide clear method and process of security requirements identification. We propose a process that software developers can build application specific security requirements from state transition diagrams at the security threat location. The proposed process consists of building model and identifying application specific security requirements. The state transition diagram is constructed through subprocesses i) the identification of security threat locations using security failure data based on the point that attackers exploit software vulnerabilities and attack system assets, ii) the construction of a state transition diagram which is usable to protect, mitigate, and remove vulnerabilities of security threat locations. The identification Process of application specific security requirements consist of i) the analysis of the functional requirements of the software, which are decomposed into a DFD(Data Flow Diagram; the identification of the security threat location; and the appliance of the corresponding state transition diagram into the security threat locations, ii) the construction of the application specific state transition diagram, iii) the construction of security requirements based on the rule of the identification of security requirements. The proposed method is helpful to identify the security requirements easily at an early phase of software development.

• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.815-820
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• 2014

We applied the two-color resonant two-photon ionization and mass-analyzed threshold ionization techniques to record the vibronic and cation spectra of 2,4-difluorophenol. As supported by our theoretical calculations, only the cis form of 2,4-difluorophenol involves in the two-photon photoexcitation and pulsed field ionization processes. The band origin of the $S_1{\leftarrow}S_0$ electronic transition of cis-2,4-difluorophenol appears at 35 647 ${\pm}2cm^{-1}$ and the adiabatic ionization energy is determined to be 70 $030{\pm}5cm^{-1}$, respectively. Most of the observed active vibrations in the electronically excited $S_1$ and cationic ground $D_0$ states mainly involve in-plane ring deformation vibrations. Comparing these data of cis-2,4-difluorophenol with those of phenol, cis-2-fluorophenol, and 4-fluorophenol, we found that there is an additivity rule associated with the energy shift resulting from the additional fluorine substitution.

• Journal of Korean Institute of Industrial Engineers
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• v.34 no.3
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• pp.308-317
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• 2008

This research investigates economic characteristics of 2 of 2 runs rules under the Shewhart $\bar{X}$ control chart scheme. A Markov chain approach is employed in order to calculate the in-control average run length (ARL) and the average length of analysis cycle. States of the process are defined according to the process conditions at sampling time and transition probabilities are derived from the state definitions. A steady state cost function is constructed based on the Lorezen and Vance(1986) model. Numerical examples show that 2 of 2 runs rules are economically superior to the Shewhart $\bar{X}$ chart in many cases.

• Polymer(Korea)
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• v.25 no.2
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• pp.226-232
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• 2001

The properties of poly(ethylene terephthalate) (PET)/maleic anhydride-grafted polypropylene (MAgPP)/poly(styrene-co-maleic anhydride)(PScMA) ternary blend were investigated. The ternary blend was immiscible based on the glass transition temperatures measured by dynamic mechanical analyzer (DMA). The degradation of MAgPP during melt mixing for 30 min at 280$^{\circ}C$ did not affect the properties of the ternary blend. The interaction among the components was confirmed from the rheological properties, which was increased with the PSCMA contents. In terms of the mechanical properties, it was observed to satisfy the mixture rule for a multiple system.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.89-94
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• 2011

The mechanism of the cycloaddition reaction of forming germanic bis-heterocyclic compound between singlet dimethylgermylene carbene and acetone has been investigated with CCSD(T)//B3LYP/6-$31G^*$ method. From the potential energy profile, it can be predicted that, this reaction has one dominant channel. The presented rule of this dominant channel is that the two reactants firstly form a four-membered ring carbene (RC4) through the [2+2] cycloaddition reaction. Due to $sp^2$ hybridization of carbene C atom in RC4, RC4 further combines with acetone to form a reactant complexe (RC5). Due to the further $sp^3$ hybridization of carbene C atom in RC4, RC5 isomerizes to a germanic bisheterocyclic compound (P6) via the transition state (TS5).

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.1195-1198
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• 1993

We investigate a systematic design procedure of automated rule generation of fuzzy logic based controller for uncertain dynamic systems such as an engine dynamic model.“Automated Tuning”means autonomous clustering or collection of such meaningful transitional relations in the state-space. Optimal control strategies are included in the design procedures, such as minimum squared error, minimum time, minimum energy or combined performance criteria. Fuzzy feedback control systems designed by the cell-state transition method have the properties of closed-loop stability, robustness under parameter variabtions, and a certain degree of optimality. Most of all, the main advantage of the proposed approach is that reliability can be potentially increased even if a large grain of uncertainty is involved within the control system under consideration. A numerical example is shown in which we apply our strategic fuzzy controller design to a highly nonlinear model of engine idle speed contr l.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.10a
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• pp.652-655
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• 2018

과반수 문제는 전역 문제(global problem) 문제이기 때문에 국소 정보(local information)를 이용해야 하는 셀룰러 오토마타(cellular automata; CA) 상에서 풀기 어려운 문제이다. 본 논문에서는 일차원 CA에서 과반수 문제를 푸는 CA을 찾는 방법을 제안한다. 상태전이 함수를 CA에서 일반적으로 사용되는 규칙 표(rule table)가 아닌 CMR(conditionally matching rules)로 나타내고 진화 알고리즘을 적용하였다. 제안한 방법으로 다수의 서로 다른 규칙들을 찾아낼 수 있었고 찾아낸 규칙은 이전 연구에서 찾아낸 규칙과 유사한 성능을 보여주었다. CA의 문제를 해결하는데 CMR에 진화 알고리즘을 적용하는 것이 효용성이 있음을 보였다.

• Bulletin of the Korean Chemical Society
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• v.16 no.10
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• pp.957-968
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• 1995

Generalized Multichannel Quantum Defect theory (MQDT) was implemented to the vibrational predissociation of triatomic van der Waals molecules in the previous paper [Bull. Korean Chem. Soc, 12, 228 (1991)]. Implementation was limited to the calculation of the scattering matrix. It is now extended to the calculation of the predissociation spectra and the final rotational distribution of the photofragment. The comparison of the results with those obtained by other methods, such as Golden-rule type calculation, infinite order sudden approximation (IOS), and close-coupling method, shows that the implementation is successful despite the fact that transition dipole moments show more energy dependence than other quantum defect parameters. Examination of the short-range channel basis functions shows that they resemble angle-like functions and provide the validity of the IOS approximation. Besides the validity of the latter, only a few angles are found to play the major role in photodissociation. In addition to the implementation of MQDT, more progress in MQDT itself is made and reported here.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.7
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• pp.119-126
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• 2018

The Slaughterhouse is the place where animals are butchered for food. This study is to investigate the establishment and transition of slaughterhouse operated in Busanbu(釜山府) as public facilities during Japanese Colonial Period. It was established in relation to the application of hygienics which the idea of modern natural science and technology produced at that time. The establishment of slaughterhouse was based on the leading knowledge of public health. It also provided important revenues for the local government and became one of the techniques of Japanese Colonial Rule. The slaughterhouse was turned into the public management in 1921 and had to be shifted twice. Eventually, it had an effect on the culture of food greatly.