• Journal of Environmental Impact Assessment
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• v.17 no.2
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• pp.133-141
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• 2008

The loss, alteration, and fragmentation of habitat have led to a reduction of biodiversity. The growing awareness of the negative effects of habitat fragmentation on natural systems has resulted in conservation strategy that is concerned with not only population and habitat level but also ecosystem and landscape level. Especially, ecological network to link core areas or major habitat patches is one of the most important issues. Recently, landscape connectivity is increasingly used in decision making for fragmented landscape management in order to conserve the biodiversity in the regional scale. The objective of this study was to find potential forest as a ecological corridor in Go-yang city, Gyung-gi province using cost-distance modelling method that can measure connectivity based on animal movement. 'Least cost-distance' modelling based on functional connectivity can be useful to establish ecological network and biodiversity conservation plan. This method calculates the distance modified with the cost to move between habitat patches based on detailed geographical information on the landscape as well as behavioural aspects of the animal movement. The least cost-distance models are based on two biologically assumptions: (1) dispersers have complete knowledge of their surroundings, and (2) they do select the least cost route from this information. As a result of this study, we can find wildlife moving route for biodiversity conservation. The result is very useful for long-term aspect of biodiversity conservation plan in regional scale, because this is reflection of geographical information and behavioural aspects of the animal movement.

• Computers and Concrete
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• v.1 no.3
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• pp.325-354
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• 2004

Slabs in buildings and bridge decks, which are restrained against lateral displacements at the edges, have ultimate strengths far in excess of those predicted by analytical methods based on yield line theory. The increase in strength has been attributed to membrane action, which is due to the in-plane forces developed at the supports. The benefits of compressive membrane action are usually not taken into account in currently available design methods developed based on plastic flow theories assuming concrete to be a rigid-plastic material. By extending the existing knowledge of compressive membrane action, it is possible to design slabs in building and bridge structures economically with less than normal reinforcement. Recent research on building and bridge structures reflects the importance of membrane action in design. This paper describes the finite element modelling of membrane action in reinforced concrete slabs through optimisation of a simple concrete model. Through a series of parametric studies using the simple concrete model in the finite element simulation of eight fully clamped concrete slabs with significant membrane action, a set of fixed numerical model parameter values is identified and computational conditions established, which would guarantee reliable strength prediction of arbitrary slabs. The reliability of the identified values to simulate membrane action (for prediction purposes) is further verified by the direct simulation of 42 other slabs, which gave an average value of 0.9698 for the ratio of experimental to predicted strengths and a standard deviation of 0.117. A 'deflection factor' is also established for the slabs, relating the predicted peak deflection to experimental values, which, (for the same level of fixity at the supports), can be used for accurate displacement determination. The proposed optimised concrete model and finite element procedure can be used as a tool to simulate membrane action in slabs in building and bridge structures having variable support and loading conditions including fire. Other practical applications of the developed finite element procedure and design process are also discussed.

• Nuclear Engineering and Technology
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• v.38 no.2
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• pp.147-154
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• 2006

Thermal fatigue of the coolant circuits of PWR plants is a major issue for nuclear safety. The problem is especially accute in mixing zones, like T-junctions, where large differences in water temperature between the two inlets and high levels of turbulence can lead to large temperature fluctuations at the wall. Until recently, studies on the matter had been tackled at EDF using steady methods: the fluid flow was solved with a CFD code using an averaged turbulence model, which led to the knowledge of the mean temperature and temperature variance at each point of the wall. But, being based on averaged quantities, this method could not reproduce the unsteady and 3D effects of the problem, like phase lag in temperature oscillations between two points, which can generate important stresses. Benefiting from advances in computer power and turbulence modelling, a new methodology is now applied, that allows to take these effects into account. The CFD tool Code_Saturne, developped at EDF, is used to solve the fluid flow using an unsteady L.E.S. approach. It is coupled with the thermal code Syrthes, which propagates the temperature fluctuations into the wall thickness. The instantaneous temperature field inside the wall can then be extracted and used for structure mechanics computations (mainly with EDF thermomechanics tool Code_Aster). The purpose of this paper is to present the application of this methodology to the simulation of a straight T-junction mock-up, similar to the Residual Heat Remover (RHR) junction found in N4 type PWR nuclear plants, and designed to study thermal striping and cracks propagation. The results are generally in good agreement with the measurements; yet, in certain areas of the flow, progress is still needed in L.E.S. modelling and in the treatment of instantaneous heat transfer at the wall.

• Smart Structures and Systems
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• v.26 no.4
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• pp.495-506
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• 2020

Monitoring of complex processes faces several challenges mainly due to the lack of relevant sensory information or insufficient elaborated decision-making strategies. These challenges motivate researchers to adopt complex data processing and analysis in order to improve the process representation. This paper presents the development and implementation of quality monitoring framework based on a model-driven approach using embedded artificial intelligence strategies. In this work, the strategies are applied to the supervision of a microfabrication process aiming at showing the great performance of the framework in a very complex system in the manufacturing sector. The procedure involves two methods for modelling a representative quality variable, such as surface roughness. Firstly, the hybrid incremental modelling strategy is applied. Secondly, a generalized fuzzy clustering c-means method is developed. Finally, a comparative study of the behavior of the two models for predicting a quality indicator, represented by surface roughness of manufactured components, is presented for specific manufacturing process. The manufactured part used in this study is a critical structural aerospace component. In addition, the validation and testing are performed at laboratory and industrial levels, demonstrating proper real-time operation for non-linear processes with relatively fast dynamics. The results of this study are very promising in terms of computational efficiency and transfer of knowledge to manufacturing industry.

• Korean Journal of Social Welfare
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• v.60 no.3
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• pp.59-82
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• 2008

This study investigated the effect of spouse attitude of psychiatric patients on relapse. The research was based on the concept that spouses' attitudes toward mental illness influences relapse, mediated by marital relationship and social adaptation. Data were collected from 102 of the psychiatrically disordered who were married, and analyzed through Structural Equation Modelling to validate causal paths and mediator effects of the variables. The marital relationship was shown to act as a mediator between spouse attitude and social adaptation, while social adaptation showed a complete mediation effect between marital relationship and relapse. Thus, spouse attitude towards mental illness was shown to have a statistically meaningful effect on relapse indirectly and through sequential mediation effect of marital relationship and social adaptation. This study proposes the facilitation of counseling and training programs to improve the marital relationships of psychiatric patients. The emphasis is on the educational program for the spouses to improve their knowledge of mental illness.

• Geophysics and Geophysical Exploration
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• v.7 no.1
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• pp.14-18
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• 2004

High levels of ambient noise and safety factors often limit the use of 'active-source' seismic methods for geotechnical investigations in urban environments. As an alternative, shear-wave velocity-depth profiles can be obtained by treating the background microtremor wave field as a stochastic process, rather than adopting the traditional approach of calculating velocity based on ray path geometry from a known source. A recent field test in Melbourne demonstrates the ability of the microtremor method, using only Rayleigh waves, to resolve a velocity inversion resulting from the presence of a hard, 12 m thick basalt flow overlying 25 m of softer alluvial sediments and weathered mudstone. Normally the presence of the weaker underlying sediments would lead to an ambiguous or incorrect interpretation with conventional seismic refraction methods. However, this layer of sediments is resolved by the microtremor method, and its inclusion is required in one-dimensional layered-earth modelling in order to reproduce the Rayleigh-wave coherency spectra computed from observed seismic noise records. Nearby borehole data provided both a guide for interpretation and a confirmation of the usefulness of the passive Rayleigh-wave microtremor method. Sensitivity analyses of resolvable modelling parameters demonstrate that estimates of shear velocities and layer thicknesses are accurate to within approximately $10\%\;to\;20\%$ using the spatial autocorrelation (SPAC) technique. Improved accuracy can be obtained by constraining shear velocities and/or layer thicknesses using independent site knowledge. Although there exists potential for ambiguity due to velocity-thickness equivalence, the microtremor method has significant potential as a site investigation tool in situations where the use of traditional seismic methods is limited.

• Journal of the Korean School Mathematics Society
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• v.11 no.4
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• pp.569-593
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• 2008

Since 2005 KICE-TLC has focused on the development of supporting programs for teaching consultation and pedagogical content knowledge(PCK). The purpose of this year's research was to explore types of pedagogical content knowledge(PCK, hereafter) for effective teaching mathematics topics drawn from the amended national mathematics curriculum announced in February, 2007. Based on this year's PCK research, we will develop mathematics teaching consulting program from 2009 research by field testing of developed mathematics PCK. The major source of data for this study was transcripts of audiotapes of the group discussions that took place during the regular weekly meetings where we compared and analyzed three teachers' classes. We also conducted open-ended interviews with the three teachers and collected reflective notes written by participants. This research provided teachers with an opportunity to think about what is important in the teaching of a topic and why, and to consider possibilities for future development. This research highlights the importance of teacher meetings where teachers share their expertises and insights through reflection and dialogue. By introducing the concept of PCK, examining, analyzing and modelling it in pre-service and in-service teacher education practice, we can contribute to extend teachers' professional learning. Finally, just like quality student learning, quality teaching and teacher education practices require critical reflection and careful scaffolding.

• School Mathematics
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• v.10 no.4
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• pp.489-514
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• 2008

Since 2005 KICE - TLC has focused on the development of supporting programs for teaching consultation and pedagogical content knowledge(PCK). The purpose of this year's research was to explore types of pedagogical content knowledge(PCK, hereafter) for effective teaching mathematics topics drawn from the amended national mathematics curriculum announced in February, 2007. Based on this year's PCK research, we will develop mathematics teaching consulting program from 2009 research by field testing of developed mathematics PCK. The major source of data for this study was transcripts of audiotapes of the group discussions that took place during the regular weekly meetings where we compared and analyzed three teachers' classes. We also conducted open-ended interviews with the three teachers and collected reflective notes written by participants. This research provided teachers with an opportunity to think about what is important in the teaching of a topic and why, and to consider possibilities for future development. This research highlights the importance of teacher meetings where teachers share their expertises and insights through reflection and dialogue. By introducing the concept of PCK, examining, analyzing and modelling it in pre-service and in-service teacher education practice, we can contribute to extend teachers' professional learning. Finally, just like quality student learning, quality teaching and teacher education practices require critical reflection and careful scaffolding.

• Journal of The Korean Association For Science Education
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• v.26 no.1
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• pp.88-98
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• 2006

The purpose of this study was to analyze the process of scientists' science knowledge generation by employing four creative scientists as participants. Raw protocols were collected by an intensive interview method and then analyzed by a psychological modelling procedure. The present study showed that the process of knowledge generation divided into the processes of inductive, abductive, and deductive thinking. Furthermore, the inductive process in simple and operative observation was involved in the processes of generating a question, conjecture/prediction, designing an operational method, operation, and simple observation. Also, the abductive process had two components; question generation, and hypothesis generation which consisted of analyzing questions, searching explicans, and constructing hypothesis. Finally, the deductive process involved inventing abstract test methods, inventing abstract criteria, inventing concrete test methods, inventing concrete criteria, collecting results, and evaluating hypotheses and stating conclusions.

• Journal of KIISE
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• v.44 no.11
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• pp.1178-1193
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• 2017

It is very important to understand system behaviors in collective pattern for each knowledge domain. However, there are structural limitations to represent collective behaviors because of the size of system components and the complexity of their interactions, causing the state explosion problem. Further composition with other systems is mostly impractical because of exponential growth of their size and complexity. This paper presents a practical method to model the collective behaviors, based on a new concept of domain engineering: behavior ontology. Firstly, the ontology defines each collective behavior of a system from active ontology. Secondly, the behaviors are formed in a quantifiably abstract lattice, called common regular expression. Thirdly, a lattice can be composed with other lattices based on quantifiably common elements. The method can be one of the most innovative approaches in representing system behaviors in collective pattern, as well as in minimization of system states to reduce system complexity. For implementation, a prototype tool, called PRISM, has been developed on ADOxx Meta-Modelling Platform.