• Korean Journal of Microbiology
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• v.27 no.4
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• pp.436-438
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• 1989

We propose a method for rapid evaluation and permanent record of sodium dodecyl sulfate polyacrylamide gel electrophoretic runs. This method is based on the photocopy process, rather than on photography and requires no extensive or expensive investment. Comparison of a print obtained through this method and a 35mm photography indicated, on a balanced gel, equal sensitivity.

• International Journal of Fluid Machinery and Systems
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• v.8 no.3
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• pp.142-154
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• 2015

Nowadays, computational fluid dynamics is commonly used by design engineers to evaluate and compare losses in hydraulic components as it is less expensive and less time consuming than model tests. For that purpose, an automatic tool for casing and distributor analysis will be presented in this paper. An in-house mesh generator and a Reynolds Averaged Navier-Stokes equation solver using the standard $k-{\omega}$ shear stress transport (SST) turbulence model will be used to perform all computations. Two solvers based on the C++ OpenFOAM library will be used and compared to a commercial solver. The performance of the new fully coupled block solver developed by the University of Lucerne and Andritz will be compared to the standard 1.6ext segregated simpleFoam solver and to a commercial solver. In this study, relative comparisons of different geometries of casing and distributor will be performed. The present study is thus aimed at validating the block solver and the tool chain and providing design engineers with a faster and more reliable analysis tool that can be integrated into their design process.

• International Journal of Fluid Machinery and Systems
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• v.8 no.3
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• pp.209-219
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• 2015

A robust multi-fidelity optimization methodology has been developed, focusing on efficiently handling industrial runner design of hydraulic Francis turbines. The computational task is split between low- and high-fidelity phases in order to properly balance the CFD cost and required accuracy in different design stages. In the low-fidelity phase, a physics-based surrogate optimization loop manages a large number of iterative optimization evaluations. Two derivative-free optimization methods use an inviscid flow solver as a physics-based surrogate to obtain the main characteristics of a good design in a relatively fast iterative process. The case study of a runner design for a low-head Francis turbine indicates advantages of integrating two derivative-free optimization algorithms with different local- and global search capabilities.

• Journal of Korean Society of Forest Science
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• v.90 no.5
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• pp.619-631
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• 2001

Since the development of a new paradigm of sustainable forest management, concerns have been focused on how the sustainability of forests will be assessed and measured objectively. This study examined the conceptual displacement on what is sustainability of forests, and analyzed the progress made by international and regional initiatives on criteria and indicators for sustainable forest management in terms of comparability and compatibility. Regarding data availability and applicability of criteria and indicators for sustainable forest management, the data reports gathered from Montreal Process member countries were analyzed. Within this context, Korean case were examined, using all possible existing information sources such as Forest Statistics, on 6 items of concepts of criteria and indicators, degree of difficulties, measurement units, data availabilities, problems and needs of future improvements for data gathering. The study also analyzed the applicability of criteria and indicators for sustainable forest management.

• International Journal of Fluid Machinery and Systems
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• v.2 no.4
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• pp.400-408
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• 2009

Optimization of seal geometries can reduce significantly the energetic losses in a hydraulic seal [1], especially for high head runner turbine. In the optimization process, a reliable prediction of the losses is needed and CFD is often used. This paper presents numerical experiments to determine an adequate CFD model for straight, labyrinth and stepped hydraulic seals used in Francis runners. The computation is performed with a finite volume commercial CFD code with a RANS low Reynolds turbulence model. As numerical computations in small radial clearances of hydraulic seals are not often encountered in the literature, the numerical results are validated with experimental data on straight seals and labyrinth seals. As the validation is satisfactory enough, geometrical optimization of hydraulic seals using CFD will be studied in future works.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.733-743
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• 1989

This paper deals with the control of system with controlled jump Markov disturbances. A such formulation was used by Boukas to model the planning production and maintenance of a FMS with failure machines. The optimal control problem of systems with controlled jump Markov process is addressed. This problem describes the planning production and preventive maintenance of production systems. The optimality conditions in both cases finite and infinite horizon, are derived. A numerical example is presented to validate the proposed results.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.1129-1132
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• 1993

This paper presents the idea of a neural fuzzy controller with application to the control of an industrial machining process. The structure of such a controller, which links the idea of a fuzzy controller and a neural network, is suggested. Results of comparative simulations indicate that the proposed neural fuzzy controller performs equally well as a fuzzy logic controller; moreover, it is more flexible and allows faster data processing.

• International Journal of Fluid Machinery and Systems
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• v.8 no.4
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• pp.283-293
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• 2015

The effect of the inlet swirling flow in a hydraulic turbine draft tube is a very complex phenomenon, which has been extensively investigated both theoretically and experimentally. In fact, the finding of the optimal flow distribution at the draft tube inlet in order to get the best performance has remained a challenge. Thus, attempting to answer this question, it was assumed that through an automatic optimization process a Genetic Algorithm would be able to manage a parameterized inlet velocity profile in order to achieve the best flow field for a particular draft tube. As a result of the optimization process, it was possible to obtain different draft-tube flow structures generated by the automatic manipulation of parameterized inlet velocity profiles. Thus, this work develops a qualitative and quantitative analysis of these new draft tube flow field structures provoked by the redesigned inlet velocity profiles. The comparisons among the different flow fields obtained clearly illustrate the importance of the flow uniformity at the end of the conduit. Another important aspect has been the elimination of the re-circulating flow area which used to promote an adverse pressure gradient in the cone, deteriorating the pressure recovery effect. Thanks to the evolutionary optimization strategy, it has been possible to demonstrate that the optimized inlet velocity profile can suppress or mitigate, at least numerically, the undesirable draft tube flow characteristics. Finally, since there is only a single swirl number for which the objective function has been minimized, the energy loss factor might be slightly affected by the flow rate if the same relation of the axial-tangential velocity components is maintained, which makes it possible to scale the inlet velocity field to different operating points.

• Journal of the Institute of Convergence Signal Processing
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• v.2 no.1
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• pp.44-52
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• 2001

This paper describes an off-line method for recognizing totally unconstrained handwritten digits using modified chaotic neural networks(MCNN). The chaotic neural networks(CNN) is modified to be a useful network for solving complex pattern problems by enforcing dynamic characteristics and learning process. Since the MCNN has the characteristics of highly nonlinear dynamics in structure and neuron itself, it can be an appropriate network for the robust classification of complex handwritten digits. Digit identification starts with extraction of features from the raw digit images and then recognizes digits using the MCNN based classifier. The performance of the MCNN classifier is evaluated on the numeral database of Concordia University, Montreal, Canada. For the relative comparison of recognition performance, the MCNN classifier is compared with the recurrent neural networks(RNN) classifier. Experimental results show that the classification rate is 98.0%. It indicates that the MCNN classifier outperforms the RNN classifier as well as other classifiers that have been reported on the same database.

• Korean Institute of Interior Design Journal
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• v.26 no.5
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• pp.16-24
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• 2017

This study examines Safdie's design philosophy: place, purpose, and process and design strategies found in museum buildings. Safdie, influenced by personal background as immigrant, education of McGil University in Canada, apprenticeship from Louis Kahn, is one of the most recognized architects who designed renowned public and cultural buildings after Habitat 67 in Montreal, Canada. In order to reveal design strategies his eight museum buildings has been selected and analyzed in terms of interpretation of context, program presented in floor plan and section design, and the process of integrity found in structure and material. The results of this paper can be summarized as follows: 1) Reflection of existing context and regeneration of the locality has been in a creative way to reinforce the sense of place. 2) The layout of major and gallery space is determined according to the Safdie's interpretation of the site context and this can be categorized into three types. 3) Integration of the innovative structural frame and material has been experimented by using tartan grid and toroid form in the major and gallery spaces. This study is intended to reevaluate the significance of Safdie's design approach to building uniqueness of the site, program and tectonic.