• Journal of KIISE:Computer Systems and Theory
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• v.37 no.3
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• pp.138-146
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• 2010

It is well known that many biological networks are very robust against various types of perturbations, but we still do not know the mechanism of robustness. In this paper, we find that there exist a number of feedback loops in a real biological network compared to randomly generated networks. Moreover, we investigate how the topological property affects network robustness. To this end, we properly define the notion of robustness based on a Boolean network model. Through extensive simulations, we show that the Boolean networks create a nearly constant number of fixed-point attractors, while they create a smaller number of limit-cycle attractors as they contain a larger number of feedback loops. In addition, we elucidate that a considerably large basin of a fixed-point attractor is generated in the networks with a large number of feedback loops. All these results imply that the existence of a large number of feedback loops in biological networks can be a critical factor for their robust behaviors.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.7
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• pp.440-447
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• 2006

Grid computing is the complex deployments of various hardware and software components. The Grid environment should provide a mechanism for real-time monitoring and notification. It is very important to implement a monitoring mechanism in the Grid environment. Most existing monitoring systems only focus on their own requirements. With the development of Grid computing technology, the extensible monitoring systems become more and more feasible and popular. In this paper, we describe our research and development works on M-Mon, a novel framework for the flexible and adaptive Grid monitoring system. M-Mon system focuses on some critical issues like scalability, reusability, runtime extensibility, protocol transparency and uniform data representation. To provide interoperability with other monitoring systems and to reuse legacy facilities with a minimum effort, our monitoring system has been developed using service-oriented architecture.

• International Journal of Highway Engineering
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• v.10 no.4
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• pp.213-224
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• 2008

Flexible pavement responses to vehicular loading, such as critical stresses and strains, in each pavement layer, could be predicted by the multilayered elastic analysis. However, multilayered elastic theory suffers from major drawbacks including spatial dimension of a numerical model, material properties considered in the analysis, boundary conditions, and ill-presentation of tire-pavement contact shape and stresses. To overcome these shortcomings, three-dimensional finite element (3D FE) models are developed and numerical analyses are conducted to calculate pavement responses to moving load in this study. This paper introduces a methodology for an effective 3D FE to simulate flexible pavement structure. It also discusses the mesh development and boundary condition analysis. Sensitivity analyses of flexible pavement response to loading are conducted. The infinite boundary conditions and time-dependent history of calculated pavement responses are considered in the analysis. This study found that the outcome of 3D FE implicit dynamic analysis of flexible pavement that utilizes appropriate boundary conditions, continuous moving load, viscoelastic hot-mix asphalt model is comparable to field measurements.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.21 no.2
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• pp.142-150
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• 1985

In this paper, stress distribution were given in consideration of bending effects in hemi-spherical shell and a modified equation of buckling load was represented with implicating the effects of plastic deformations and shape parameters. Especially, the distributions of shell near it's vertex were analyzed numerically, according to several cases of loading. For the sake of more good estimation of plastic dissipating energy, we used the yield-line method from plate theory. The modified criterion of bucking, P super(*) sub(cr), that was suggested in this study, was applied to SUS 302 stain-less steel hemi-spherical shell which had it's Poisson's ratio and Young's modulus with 0.33 and 19700 kg/mm$^2$. From some experiments and comparisons with other results, 재 suggested the critical buckling-load-equation with P super(*) sub(cr)=2E super(*).(t super(2)/a super(2)).{3(1-ν super(*2)} and computed the buckling initiation load with this equation. Because these result from modified criterion have more coincidence than previous one, we prospect this equation can be magnified it's utilities to the other materials.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.5
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• pp.196-208
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• 2005

In multiprocessor systems, interconnection network design is critical for overall system performance. Popular interconnection networks, which are generally considered, are meshes, rings, and hierarchical rings. In this paper, we propose (')Torus Ring('), which is a modified version of hierarchical ring. Torus Ring has the same complexity as the hierarchical rings, but the only difference is the way it connects the local rings. It has an advantage over the hierarchical rings when the destination of a packet is the neighbor local ring in the reverse direction. Though the average number of hops in Torus Ring is equal to that of the hierarchical rings when assuming the uniform distribution of each transaction, the benefits of the number of hops are expected to be larger because of the spatial locality in the real environment of parallel programming. In the simulation results, latencies in the interconnection network are reduced by up to 19$\%$, and the execution times are reduced by up to 10$\%$.

• Journal of Engineering Education Research
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• v.5 no.1
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• pp.50-58
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• 2002

The most important point in electronic learning(e-learning) is to gain the learning sympathy by improving interaction among the learners, instructors and operators around instruction contents. But it is necessary for the instructor to have active assistance of an administrator as a supporter and an operator because instructors do not accept all the learner's demands. So, operator's activity is very critical in success of e-learning. In this paper, wamine the theory of constructionism to effectively reflect the characteristic of WWW, and to build up a foundation of the web-based integrated e-learning circumstance. The circumstance is composed of 3 modules of the learner, instructor and the administrator. This aims to coordinate instruction functions in order to improve the effect of learning and to intensify the interaction. This paper presents the design and implementation of an e-learning system which is focused on the administrator's module to effectively support the operator's activity. As a result of this research, the system can be used in building up a variety of e-learning in university, that is, general training course and technical training course.

• Journal of Information Science Theory and Practice
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• v.2 no.3
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• pp.55-65
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• 2014

This study investigated the information environment of lecturers in Federal Polytechnic, Offa, Kwara State, Nigeria, in relation to their information seeking behavior, extent of use of the polytechnic library, perceptions of the resources and services of the library, level of awareness and extent of use of the open access model of scholarly communications, as well as the challenges of accessing and using information resources. It adopted the survey research method, using a questionnaire for data collection, while the descriptive statistics method was used to analyse the data, using tabular presentation and simple percentages. From a population of 280 lecturers for the study, a purposive sample of 164 was drawn. The findings showed that the lecturers' information needs are focused on online use; they hardly use the polytechnic library due to their perceptions of the resources and services of the library. They are, to a greater extent, aware of open access initiatives, but do not publish in open access outlets, while various challenges affect their access and use of information resources for teaching and research. A recommendation was made, among others, that the polytechnic management should pay more critical attention to the library especially in the areas of adequate, current and comprehensive collections on all the programmes of the institution, as well as the provision of wireless internet services on the campus through a public-private partnership arrangement.

• Journal of Gifted/Talented Education
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• v.21 no.2
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• pp.575-589
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• 2011

The aims of this study are to investigate how Kepler found a scientific problem for the retinal image theory and to investigate how the science high-school students respond when the same situation is applied to them. And their results was compared with general high-school students' results. Kepler found the scientific problem in the eye vision through the critical analysis of contemporary theories of vision, based on his relevant knowledge of optics. When we applied the same situation to the Korean science high school and general high-school students, only a few of science high-school students found the scientific problem as same as Kepler's finding. From the results, it is suggested that in development of creativity teaching material, the situations like Kepler's problem finding need to be included in the programs.

• Journal of the Korean Geographical Society
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• v.45 no.5
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• pp.609-627
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• 2010

Finding the ideal location for your business is one of the most critical and important steps you will have to undertake. Otherwise, done in the wrong way you will only end up paying an expensive cost for an unsuitable location. Therefore to select the perfect location for your business, this study makes a reasonable and simple model for retail shops by calculating occupation population for each store applying Huffs "Probability Theory" to Hypermarket in Seoul. Then this study, based on occupation population, has divided every unit section (dong scale) into 4 market types which represent the state of the competitive markets, including monopoly, oligopoly, competitive, and noncompetitive markets. Consequently, the most reasonable place to locate a new store is where it can take most of the customers, that is, a place which can take non-competitive market as much as possible and is distant far enough from competitive market where competition is severe.

• Journal of The Korean Association For Science Education
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• v.23 no.1
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• pp.21-34
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• 2003

This study aims to show how scientifically gifted students think in terms of Thinking Style Inventory based on Sternberg's theory of mental self-government and to examine the relationships between their thinking styles, intelligence and creativity. Two hundred and sixty-six middle school students (169 boys, 97 girls) who enrolled in a gifted education program participated in this study. Results indicated that scientifically gifted students prefer legislative, liberal, judical thinking styles, in comparison to general students, known to be related to creative and critical thinking rather than executive and conventional styles. There was no significant correlation between any of thinking style sub measures and Raven' Matrices and Scientific Aptitude Test, but some correlations were found among the sub measures of thinking style and TTCT. Whereas liberal students gained high originality scores, conventional students gained low fluency scores. Also, judical thinking style showed significant correlations with originality and flexibility TTCT sub scores. In sum, this study showed the characteristics of thinking styles of scientifically gifted students and provided implications for gifted education based on the findings presented.