• Computers and Concrete
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• 제9권6호
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• pp.469-486
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• 2012

This paper presents Neuro-Fuzzy (NF) based empirical modelling of torsional strength of RC beams for the first time in literature. The proposed model is based on fuzzy rules. The experimental database used for NF modelling is collected from the literature consisting of 76 RC beam tests. The input variables in the developed rule based on NF model are cross-sectional area of beams, dimensions of closed stirrups, spacing of stirrups, cross-sectional area of one-leg of closed stirrup, yield strength of stirrup and longitudinal reinforcement, steel ratio of stirrups, steel ratio of longitudinal reinforcement and concrete compressive strength. According to the selected variables, the formulated NFs were trained by using 60 of the 76 sample beams. Then, the method was tested with the other 16 sample beams. The accuracy rates were found to be about 96% for total set. The performance of accuracy of proposed NF model is furthermore compared with existing design codes by using the same database and found to be by far more accurate. The use of NF provided an alternative way for estimating the torsional strength of RC beams. The outcomes of this study are quite satisfactory which may serve NF approach to be widely used in further applications in the field of reinforced concrete structures.

• Steel and Composite Structures
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• 제33권6호
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• pp.865-875
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• 2019

The current article proposed to develop a geometrical model for the analysis and modelling of the uniaxial functionally graded structure using the higher-order displacement kinematics with and without the presence of porosity including the distribution. Additionally, the formulation is capable of modelling three different kinds of grading patterns i.e., Power-law, sigmoid and exponential distribution of the individual constituents through the thickness direction. Also, the model includes the distribution of porosity (even and uneven kind) through the panel thickness. The structural governing equation of the porous graded structure is obtained (Hamilton's principle) and solved mathematically by means of the isoparametric finite element technique. Initially, the linear frequency parameters are obtained for different geometrical configuration via own computer code. The comparison and the corresponding convergence studies are performed for the unidirectional FG structure for the validation purpose. Finally, the impact of different influencing parameters like aspect ratio (O), thickness ratio (S), curvature ratio (R/h), porosity index (λ), type of porosity (even or uneven), power-law exponent (n), boundary condition on the free vibration characteristics are obtained for the FG panel and discussed in details.

• Asia pacific journal of information systems
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• 제2권2호
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• pp.31-54
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• 1992

Generating an action plan and obtaining commitment to achieve it is desired in organizations, but not always achieved. Whatever the reason, there is a room for an improved approach to decision making, so that people can arrive at a common understanding of a problem and commitment to action. Those are the purposes of a Decision Conferencing(DC). A DC, one example of single workstation-based GDSSs, is a two-day session attended by a group of people who attempt to resolve important issues of concern to their organization with the help of group facilitation techniques and decision analytic computer modelling. The interchange of differing perspectives on the issues is encouraged by the facilitator who attends to group processes but does not contribute to the content of discussions. Decision analysis provides a variety of structures for modelling the differing perspectives. Information and value judgements are incorporated in these models, whose results usually reveal new, higher-level perspectives on the issues. Information technology is needed to combine the part of the model and to facilitate on-the-spot replay of results. The experimental case study in this paper shows that how a DC can help a Korea's trading company to develop new, corporate level resource allocation strategies which are based on improved consensus among competing participants.

• 대한수학회논문집
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• 제35권4호
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• pp.1095-1106
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• 2020

The purpose of this paper is to introduce a new class of rings that is closely related to the class of pseudo-Krull domains. Let 𝓗 = {R | R is a commutative ring and Nil(R) is a divided prime ideal of R}. Let R ∈ 𝓗 be a ring with total quotient ring T(R) and define 𝜙 : T(R) → R_Nil(R) by ${\phi}({\frac{a}{b}})={\frac{a}{b}}$ for any a ∈ R and any regular element b of R. Then 𝜙 is a ring homomorphism from T(R) into R_Nil(R) and 𝜙 restricted to R is also a ring homomorphism from R into R_Nil(R) given by ${\phi}(x)={\frac{x}{1}}$ for every x ∈ R. We say that R is a 𝜙-pseudo-Krull ring if 𝜙(R) = ∩ R_i, where each R_i is a nonnil-Noetherian 𝜙-pseudo valuation overring of 𝜙(R) and for every non-nilpotent element x ∈ R, 𝜙(x) is a unit in all but finitely many R_i. We show that the theories of 𝜙-pseudo Krull rings resemble those of pseudo-Krull domains.

• 대한전기학회논문지:전력기술부문A
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• 제48권2호
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• pp.89-95
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• 1999

This study investigates the population model of the spread of HIV/AIDS which the infection is generated by an infectious individual in a population of susceptible. A mathematical model is presented for the transmission dynamics of HIV infection within the communities of homosexual males. The pattern on the epidemic character of HIV, the causative agent of AIDS, was analysed by the mathematical model of AIDS system which is derived according to the ecological relationship between five epidemilogic states of individuals. The computer simulation was performed using real data and the following conclusions are drawn on the basis of the simulations. 1. The model structure and the algorithm described n the thesis is good. 2. In proportion to increase Ro, the population of AIDS patient increases and the time of its widespread reaches earlier. 3. The AIDS patients will be maximum between 7 and 21 years after an attack of AIDS and widespread between 10 and 20 years. 4. Considering the properties of the incubation periods, the maximum number of infected person is increased, and the attack rate is decreased.

• 대한수학교육학회지:수학교육학연구
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• 제8권2호
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• pp.663-677
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• 1998

The development of Science and Technology and the social change require new paradigm in Education. In a traditional paradigm, learners have been regarded as a passive being and knowledge could be transmitted to learner. But within this paradigm, it is difficult to confront the social change and to develop problem solving skills in various context. This results in a new, alternative perspective, Constructive paradigm. As an alternative to the traditional settings, Constructive paradigm emphasizes the learner centered instruction. The reform movement in mathematics education including NCTM's standards revolves around this paradigm and the open education movement in our educational system is based on it. Open education values learner's interest, autonomy and internal motivation in learning. However, open education has been misunderstood by most of the teachers. It should be understood as the change of paradigm. In this study, as a way of helping students connect mathematics to their everyday lives and construct meaningful mathematical knowledge and concept, mathematical modelling is suggested. It consists of posing and specifying the real problem, formulation and constructing a mathematical model, analyzing and solving a mathematical problem. interpreting the solution and comparing with reality and communicating results. In this process, technology like computer can be a powerful tool. It can help students explore various problems more easily and concretely.

• 한국정보컨버전스학회:학술대회논문집
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• 한국정보컨버전스학회 2008년도 International conference on information convergence
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• pp.145-150
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• 2008

This thesis explores the problem of reconstructing a three-dimensional(3D) scene given a set of images or image sequences of the scene. It describes efficient methods for the 3D reconstruction of static and dynamic scenes from stereo images, stereo image sequences, and images captured from multiple viewpoints. Novel methods for image-based and volumetric modelling approaches to 3D reconstruction are presented, with an emphasis on the development of efficient algorithm which produce high quality and accurate reconstructions. For image-based 3D reconstruction a novel energy minimisation scheme, Iterated Dynamic Programming, is presented for the efficient computation of strong local minima of discontinuity preserving energyy functions. Coupled with a novel morphological decomposition method and subregioning schemes for the efficient computation of a narrowband matching cost volume. the minimisation framework is applied to solve problems in stereo matching, stereo-temporal reconstruction, motion estimation, 2D image registration and 3D image registration. This thesis establishes Iterated Dynamic Programming as an efficient and effective energy minimisation scheme suitable for computer vision problems which involve finding correspondences across images. For 3D reconstruction from multiple view images with arbitrary camera placement, a novel volumetric modelling technique, Embedded Voxel Colouring, is presented that efficiently embeds all reconstructions of a 3D scene into a single output in a single scan of the volumetric space under exact visibility. An adaptive thresholding framework is also introduced for the computation of the optimal set of thresholds to obtain high quality 3D reconstructions. This thesis establishes the Embedded Voxel Colouring framework as a fast, efficient and effective method for 3D reconstruction from multiple view images.

• 한국지능시스템학회논문지
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• 제15권6호
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• pp.688-694
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• 2005

본 논문에서는 클러스터링을 뉴로-퍼지 모델에 직접 적용하여 모델을 최적화하는 방법을 제안하였다. 기존의 오차미분기반 학습을 통한 뉴로-퍼지 모델의 최적화 과정과는 달리 제안된 방법은 클러스터링 학습과 연계하여 모델을 구성하며 자율적으로 클러스터의 수를 추정하며 동시에 최적화를 수행한다. 순차적인 학습 기법에서는 각각의 학습 기법을 따로 적용하여 모델링을 실시하였으나 제안된 기법에서는 하나의 클러스터링 학습으로 전체 모델의 학습을 실시하였다. 또한 제안된 방법에서는 클러스터링이 수렴하는 만큼 전체 모델의 연산량이 감소하여 학습과정에서 발생하는 연산량 문제를 개선하였다. 시뮬레이션을 통하여 기존의 연구 결과들과 비교하여 제안된 기법의 유용성을 보였다.

• Nuclear Engineering and Technology
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• 제21권1호
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• pp.40-47
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• 1989

중성입자입사 장치의 효율적인 빔형성 구조를 목적으로 정전기장 내에서 하전 입자의 움직임을 시간의 흐름에 따라 계산해 볼 수 있는 프로그램을 만들어 입자 모사 모형을 찾았다. 가속관 내의 입자의 움직임은 일정 시간 간격으로 계산하였고 전위는 유한차분법에 의해 Poisson 방정식에서 구하였다. 행렬식은 반복해법인 successive overrelaxation법을 사용하였고 전하밀도와 임자에 미치는 전기장의 힘을 구할 때는 cloud-in-cell모델을 사용하였다. 이 전자계산 코드를 사용하여 가속관 내 전극의 여러 조건들을 변화시켜가면서 빔형성 구조의 최적 설계를 수행하였다. 중성자 입사 장치의 가속관에서 가속 감속-전극간의 간격변화, 감속전극의 두께 변화, 가속 전극의 형태변화 등을 통하여 이들이 빔의 모양에 끼치는 영향을 조사하여 몇 가지 경우에 있어서 일정한 시간 간격으로 나타나는 입자들의 움직임을 예시하였다. 이 입자 모사모형을 통하여 가속전극의 형태가 빔 퍼짐에 가장 주요한 역할을 하는 것을 알았다.

• International Journal of Computer Science & Network Security
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• 제22권1호
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• pp.347-357
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• 2022

The aim of the study is to model demand for full-time Bachelor's Degree Programs in Hospitality and Catering, taking into account the influence of the main determinants in the COVID-19 pandemic. The research used methods of algorithms, correlation and regression analysis, ANOVA, graphical method, deduction and induction, abstraction, etc. It was found that the demand for full-time Bachelor's Degree Programs in Hospitality and Catering is price elastic. It has been argued that it is useful to consider both price and non-price determinants when modelling demand for full-time Bachelor's Degree Programs in Hospitality and Catering. It is proved that the main determinants of demand for full-time Bachelor's Degree Programs in Hospitality and Catering are full-time tuition fee, maximum government order, license volume and Consolidated Ranking of a higher education institution (HEI). In this case, the applicant decides to enrol in a full-time Bachelor's Degree Program in Hospitality and Catering, guided by the optimal ratio of tuition fee and the prestige of the HEI.