• Management & Information Systems Review
• /
• v.2
• /
• pp.169-193
• /
• 1998

Case- based reasoning(CBR) offers a new approach for developing knowledge based systems. Unlike the rule-based paradigm, in which domain knowledge is encoded in the form of production rules, in the case-based approach the problem solving experience of the domain expert is encoded in the form of cases stored in a casebase(CB). CBR allows a reasoner (1) to propose solutions in domains that are not completely understood by the reasoner, (2) to evaluate solutions when no algorithmic method is available for evaluation, and (3) to interprete open-ended and ill-defined concepts. CBR also helps reasoner (4) take actions to avoid repeating past mistakes, and (5) focus its reasoning on important parts of a problem. Owing to the above advantages, CBR has successfully been applied to many kinds of problems such as design, planning, diagnosis and instruction. In this paper, I propose case-based DSS(CBDSS). CBDSS is an intelligent DSS using CBR technique. CBDSS consists of interface, case-based reasoner, maintainer, casebase management system, domain dependent CB, domain independent CB, and so on.

• Journal of information and communication convergence engineering
• /
• v.8 no.3
• /
• pp.312-316
• /
• 2010

Conformal mapping has been a familiar tool of science and engineering for generations. The methods of numerical mapping are usually classified into those which construct the map from standard domain such as the unit disk onto the 'problem domain', and those which construct the map in the reverse direction. We treat numerical conformal mapping from the unit disk onto the Jordan regions as the problem domain in this paper. The traditional standard methods of this type are based on Theodorsen integral equation. Wegmann's method is well known as a Newton-like efficient one for solving Theodorsen equation. An improved method for convergence by applying low frequency pass filter to the Wegmann's method was proposed. In this paper we propose an effective algorithm for numerical conformal mapping based on the improved method. This algorithm is able to determine the discrete numbers and initial values automatically in accordance with the given region and the required accuracy. This results come from analyzing the shape of given domain as seen in the Fourier Transform.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.18 no.1
• /
• pp.17-26
• /
• 2014

This paper presents development of an improved domain decomposition method for large scale structural problem that aims to provide high computational efficiency. In the previous researches, we developed the domain decomposition algorithm based on augmented Lagrangian formulation and proved numerical efficiency under both serial and parallel computing environment. In this paper, new computational analysis by the proposed domain decomposition method is performed. For this purpose, reduction in computational time achieved by the proposed algorithm is compared with that obtained by the dual-primal FETI method under serial computing condition. It is found that the proposed methods significantly accelerate the computational speed for a linear structural problem.

• Honam Mathematical Journal
• /
• v.37 no.3
• /
• pp.299-315
• /
• 2015

In this paper, we study the first-order system least-squares (FOSLS) spectral method for parabolic partial differential equations. There were lots of least-squares approaches to solve elliptic partial differential equations using finite element approximation. Also, some approaches using spectral methods have been studied in recent. In order to solve the parabolic partial differential equations in parallel, we consider a parallel numerical method based on a hybrid method of the frequency-domain method and first-order system least-squares method. First, we transform the parabolic problem in the space-time domain to the elliptic problems in the space-frequency domain. Second, we solve each elliptic problem in parallel for some frequencies using the first-order system least-squares method. And then we take the discrete inverse Fourier transforms in order to obtain the approximate solution in the space-time domain. We will introduce such a hybrid method and then present a numerical experiment.

• Journal of Korea Multimedia Society
• /
• v.24 no.10
• /
• pp.1319-1325
• /
• 2021

It is important to remove fog for accurate object recognition and detection during preprocessing because images taken in foggy adverse weather suffer from poor quality of images due to scattering and absorption of light, resulting in poor performance of various vision-based applications. This paper proposes an end-to-end deep learning-based single image de-fogging method using U-Net architecture. The loss function used in the algorithm is a loss function based on Mahalanobis distance with fog features, which solves the problem of domain shifts, and demonstrates superior performance by comparing qualitative and quantitative numerical evaluations with conventional methods. We also design it to generate fog through the VGG19 loss function and use it as the next training dataset.

• Structural Engineering and Mechanics
• /
• v.77 no.3
• /
• pp.315-327
• /
• 2021

Here, in this research we have studied a two dimensional problem in a homogeneous orthotropic magneto-thermoelastic medium with higher order dual-phase-lag heat transfer with combined effects of rotation and hall current in generalized thermoelasticity due to time harmonic sources. As an application the bounding surface is subjected to uniformly distributed and concentrated loads (mechanical and thermal source). Fourier transform technique is used to solve the problem. The expressions for displacement components, stress components and temperature change are derived in frequency domain. Numerical inversion technique has been used to obtain the results in physical domain. The effect of frequency has been depicted with the help of graphs.

• The Journal of Pediatrics of Korean Medicine
• /
• v.27 no.1
• /
• pp.26-35
• /
• 2013

Objectives The purpose of this study is to analyze the factors that cause nocturnal crying. Methods This clinical study has been carried out with 133 infants and children, who visited to the department of Pediatrics, ${\bigcirc}{\bigcirc}$ Oriental Medical Hospital from September 2012 to October 2012. Patient's guardian filled out the questionnaire consisting of pregnancy-birth domain, child care domain, sleep domain, nocturnal crying domain and other domains. We used PASW Statistics 18.0 to analyze each factors by Chi-square test, Fisher's exact test and independent samples t test. Results The prevalence of nocturnal crying between "frequently changing sleep posture group" and "stable sleep posture group" were significantly different (p=0.002, OR=3.557). The prevalence of nocturnal crying between "sleep problem group" and "no sleep problem group" were significantly different (p=0.022, OR=4.052). The nocturnal crying prevalence of the rest of the groups had no significant difference. Conclusions The frequently changing sleep posture increases the risk of nocturnal crying, and the presence of sleep problem increases the risk of nocturnal crying.

• Journal of information and communication convergence engineering
• /
• v.6 no.2
• /
• pp.222-227
• /
• 2008

The important problem in designing a Fuzzy Logic Controller(FLC) is generation of fuzzy control rules and it is usually the case that they are given by human experts of the problem domain. However, it is difficult to find an well-trained expert to any given problem. In this paper, I describes an application of genetic algorithm, a well-known global search algorithm to automatic generation of fuzzy control rules for FLC design. Fuzzy rules are automatically generated by evolving initially given fuzzy rules and membership functions associated fuzzy linguistic terms. Using genetic algorithm efficient fuzzy rules can be generated without any prior knowledge about the domain problem. In addition expert knowledge can be easily incorporated into rule generation for performance enhancement. We experimented genetic algorithm with a non-trivial vehicle controling problem. Our experimental results showed that genetic algorithm is efficient for designing any complex control system and the resulting system is robust.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.26 no.4
• /
• pp.213-221
• /
• 2013

This paper introduces a mesh continuation scheme for a one-dimensional inverse medium problem to reconstruct the spatial distribution of elastic wave velocities in heterogeneous semi-infinite solid domains. To formulate the inverse problem, perfectly-matched-layers(PMLs) are introduced as wave-absorbing boundaries that surround the finite computational domain truncated from the originally semi-infinite extent. To tackle the inverse problem in the PML-truncated domain, a partial-differential-equations(PDE)-constrained optimization approach is utilized, where a least-squares misfit between calculated and measured surface responses is minimized under the constraint of PML-endowed wave equations. The optimization problem iteratively solves for the unknown wave velocities with their updates calculated by Fletcher-Reeves conjugate gradient algorithms. The optimization is performed using a mesh continuation scheme through which the wave velocity profile is reconstructed in successively denser mesh conditions. Numerical results showed the robust performance of the mesh continuation scheme in reconstructing target wave velocity profile in a layered heterogeneous solid domain.

• Journal of Fisheries and Marine Sciences Education
• /
• v.26 no.3
• /
• pp.597-610
• /
• 2014

The purpose of this study was to inquiry of influence of Meister high school and specialized vocational high school' students on career maturity in problem solving ability domain of test for enhanced employ ability & upgraded proficiency. Research subjects and region were sophomore students of each one of Meister high schools and specialized vocational high schools in Gwangju region. The sample(N=481) was drawn from 2 high schools and collected data were analyzed with SPSS using t-test, Pearson correlation and Levene's test. Items of problem solving ability domain of test for enhanced employ ability & upgraded proficiency were used test items developed in 2012. Career maturity test in Careernet site was used test items developed in 2001 which was made up 3 domains such as attitude, ability and action and 8 sub-regions such as planning, attitude on the vocation, independence, self-understanding, rational decision-making, explore of information, knowledge of hope vocation and career exploration and preparation of action, and constituted 64 items. The results were as follows. Findings of the analysis in specialized vocational high school students demonstrated the positive results of rational decision-making and explore of information in problem solving ability test for enhanced employ ability & upgraded proficiency. Comparing career maturity influence on Meister high school with specialized vocational high school students about problem solving ability domain of test for enhanced employ ability & upgraded proficiency, Meister high school students' score were more high grade than specialized vocational high school students grade.